C0RN-30YBEAN FLOUR RATIONS IN THE NUTRITION OF THE YOUNG CALF The Us© of Milk Replacors witb Limited iflhole Milk for Feeding Young Calves* Digestibility and Balance Studies with Milk and Milk Replacers CARL H. NOLLER A Thesis Submitted to the School of Graduate Studies of Michigan State University of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Dairy ProQuest Number: 10008662 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest ProQuest 10008662 Published by ProQuest LLC (2016). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106 -1346 ACKNOWLEDGMENTS The author wishes to express his sincere appreciation to Doctor C* F* Huffman* Research Professor in Dairying* and to Doctor G. M* Ward, Assistant Professor in Dairying* for their counsel, guidance and critical reading of the manuscript; and to Doctor E* P* Reineke, Professor in Physiology for his critical reading of the manuscript* The author wishes to express his gratitude to Mr. C* W* Duncan, Associate in Agriculture Chemistry, for the chemical analyses; to Doctor Frank Thorp, Jr., Professor in Animal Pathology* and Doctor J* A* Williams, Instructor in Animal Pathology* for the post mortem examinations; and to Mr* Ralph Reid, herdsman, for his help in caring for the calves* The author is also indebted to Distillers Feed Research Council, Cincinnati, Ohio, and Commercial Solvents Corporation, Terre Haute, Indiana, for the funds which helped make this investigation possible; to Lederle Laboratories, Pearl River, New York, for the Aureofao;to Commercial Solvents Corporation, Terre Haute, Indiana for the Baciferm-5; and to Distillers Feed Research Council, Cincinnati, Ohio, for the distillers dried solubles* The author wishes to express his gratitude to his wife for her encouragement, sacrifices and for the typing of this thesis* CORN-SOYBEAN FLOUR RATIONS IN THE NUTRITION OF THE YOUNG CALF The Use of Milk Replacers with Limited Whole Milk for Feeding Young Calves# Digestibility and Balance Studies with Milk and Milk Replacers# Carl H. Noller A N ABSTRACT Submitted to the School of Graduate Studies of Michigan State University of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Dairy 1955 Approved Carl H. Noller ABSTRACT Twenty-one Holstein calves were placed on three predominantly vegetable milk replacers basal, basal with 5 percent dried whey and basal with 3.5 per­ cent lactose# The three groups of calves consumed an average of 54.9, 51*9, and 50.7 lb# of whole milk, respectively, during the experimental period* The average daily gains of the calves on the basal, whey and lactose rations were 0.87*.08, 0.92^.05 and 0.87*.07 lb., respectively. The differences were not statistically significant. Growth patterns indicated the existence of a critical period in the life of the young calf from birth to approximately 25 days of age* The end of the critical period was characterized by increased growth, increased feed consumption and improved appearance of the calf. Calves receiving the whey ration had the more costive fees, smoother haircoat and were more alert* lactose appeared to have no benefit under the conditions of this experiment• Two groups of four 10-day-old male calves each were assigned to 4 X 4 Latin square metabolism studies* Fecal collections were made utilising a simplified bag technique. The apparent digestibilities of five milk replacers, evaporated milk and raw whole milk were determined. Nitrogen, calcium and phosphorus balances were determined. The effect of age of the calves on the apparent digestibilities of the various feeds was studied. One experiment was conducted with two calves to compare the digestibility of evaporated and raw whole milk in a continuous trial. The variability of the milk replacer data in the first experiment indicated the inadequacy of 2-day fecal and urine collection periods. The use of 4-day collection periods appeared to be sufficient. The mean coefficient of apparent dry matter digestion of raw whole milk was 94.R; crude protein, 90.1$ ether extract, 97.8; and nitrogen-free extract, 97.1. The dry matter of evaporated milk was 76.8 percent digested by a 10-to 14-day-old -2- Carl H. Noller Abstracts (cont*d) calf and an average of 90.0 percent hy 19-to^ 38-day-old calves. The average ap­ parent dry matter digestibility of the milk replacers increased from 25.0 per­ cent to 10-to 14-day-old calves to an average of 75.4 percent for 26-to- 38-dayold calves. Similar increases in digestibility with increased age of the calves were noted for the crude protein and nitrogen-free extract fractions. The most digestible fraction was the nitrogen-free extract and the least digestible the crude protein. The crude protein of the raw whole milk was slightly less digestible by the 10-to 14-day-old calf than in subsequent periods. For the evaporated milk it was low for the 10-to**14-day-old calf and at its maximum value ty 19 to 22 days of age. During the first collection period the crude protein of the milk replacers was considerably less digestible than that of the milks* It attained its maximum value by 26 days of age. Crude fiber was essentially indigestible throughout the experiments. Nitrogen, calcium and phosphorus retentions were greater for calves fed raw whole milk than those fed the evaporated milk or milk replacer rations. Nitrogen and phosphorus balances were low or negative in 10-to-22-day-old calves fed the milk replacer rations. The older calves had positive balances. The milk replacers used in this investigation were not satisfactorily utilized by the calf until the calf was approximately 25 days of age. TABLE OF CONTENTS INTRODUCTION ................................................. ... Page 1 PART I REVIEW OF L I T E R A T U R E ................................................. 3 Rumen Development in the Young Calf . . ......... . . . . . . 3 Use of Dried Whey and Lactose • • • • • • • • • • • • • • • • 7 Use of Calf Gruels Historical » • • * • • • • ............. • • • • * • . . 1 0 Soybean type • • • • • • • • • • • • • • • . . 11 Distillers dried solubles. • • • • . • • • . • • • . . • 1 3 Aureomycin. • • • • • • • * . . . . • • . • 13 Weaning Age • • • . • • • • • • • . • • • • • • • • • • • • • 1 4 EXPERIMENTAL PROCEDURE Selection and Assignment of Animals. Feeding and Management. ....................16 • • • • • • • • • • • • • • • • • . *16 Feed Formulation* • • • • • • • • • • * • • • • • • • • • • • 1 7 Measurement of Feed Effects Body weight............• • • • • ....................• • • I d Health and post mortem . • • • • • • • • • • • • • • • • 1 9 Feed consumption and analysis of feed* • • • • • • • • • 1 9 RESULTS................................................................ 21 D I S C U S S I O N .......................................................... .. SUMMARY................................................................ 29 TABLE OF CONTENTS (Cont*) PART II Page REVIEW OF LITERATURE The Nutritive Value of Milk Effect of processing • • • • • • • • • • • • • • • • • • 3 1 Effect of storage* • • • • • • • • • • • • • • • • • • • 3 5 The Value of Milk and Vegetable Feedstuffs* • • • • • • • * • 3 7 Digestion in the Young Calf ...................• • • • 4 2 Nitrogen Metabolism • • • • • • • • • • • • • • • • • • • • • 4 5 Calcium and Phosphorus Metabolism • • • • • • • • • • • • • • 4 8 EXPERIMENTAL PROCEDURE Experimental Design ........... • • • • • • • • • 51 Selection and Assignment of Calves* • ......... • • • • • • • 5 1 Feeding and Management. • • • • • • • • • • • • * • • * • • • 5 2 Formulation of Milk Replacers • • • • • • • • • • • • • • • • 5 5 Collection of Feces and Urine• • • • • • • • • • • • • • • • 5 6 Analytical Procedures • • • • • .............................. 61 RESULTS Experiment 1. .........• • • • • • • • • • • ................ 62 Experiment 2 » « * * * * * ............ 67 Experiment 3 ............................................ • • • • 6 7 D I S C U S S I O N ........................................................... 78 SUMMARY............................................................... 87 LITERATURE CITED ................................................... 89 A P P E N D I X ............................................................ 106 LIST OF FIGURES Page Figure I Growth curves ...................... • • • • • • • • • 2 3 Figure II Preparation of bag before cutting flap* • • • • • • Figure III Finished bag. • • • • • • • • • • • • • • • • * • • • 5 8 Figure IV Position of lower strap • • • Figure V Position of top s t r a p ........... Figure VI Attachment of pliofilm bag to top strap • • • • • • • 6 0 Figure VII Attachment of pliofilm bag to lower strap • • • • • • ........... .58 • • • • • • 5 9 • 59 60 Figure VIII Apparent dry matter digestibilities by periods— Experiment 1. . • • • • • • • • • • • • • • • • • * • 7 1 Figure IX Apparent crude protein digestibilities by periods— Experiment 1. ....................................• • 7 2 Figure X Apparent nitrogen-free extract digestibilities by periods— Experiment ! • * • • • • • • • 73 Figure XI Apparent dry matter digestibilities by periods— Experiment 3 ............. • • • • ............ • • • • • 7 4 Figure XII Apparent crude protein digestibilities by periods— Experiment 3* • • • • • • • • • • • • • • • • • • • • 75 Figure XIII Apparent nitrogen-free extract digestibilities by periods— Experiment 3* • • • • • .......... • • • • 7 6 Figure XIV Apparent digestibilities of dry matter, crude protein and nitrogen-free extract of raw whole milk, evaporated milk and milk replacers by 26- to 38-day-old calves— Experiment 3 • • • • • .......... . 7 7 LIST OF TABLES Pag® , Table 1 Table 2 Daily Feeding Schedule • • • • • • . 17 Composition of Milk Repl&cers.......... • • 18 Table 3 Chemical Analyses of Milk Replacers* • • • • • • • • • * 2 0 Table 4 Growth and Feed Consumption Data of Calves to 60 Days of Age • • • • • • • • • • • • • • • • • • • • • 2 1 Table 5 Apparent Digestibility of Milk • • • • • • • • • • • • • 3 8 Table 6 Apparent Digestibility of Various Feeds* • • • • • • 39,3s 40 Table 7 Experimental Design of Experiment 1 Showing the Age of Calves and Rations Fed • • • • • • • • • • • *53 Table 8 Experimental Design of Experiment 3 Showing the Age of Calves and Rations Fed . • • • • • • • • • • 5 3 Table 9 Composition of Daily Rations • • • • • • • • • • • • • • 5 3 Table 10 Composition of Milk Replaoer Used in Experiments 1 and 3.64 Table 11 Chemical Analyses of Feeds Used in Experiments 1 and Table 12 Average Digestibility Coefficients, Daily Balances and Their Standard Errors— Experiment 1. • • • • . . • • 3 • 55 Table 13 Analyses of Varianoe— Experiment 1 Table 14 Dry Matter Digestibility of Whole Milk and Evaporated Milk— Experiment . . . . . • * • • • 64 F.Values • • • • • • 65 65 Table 15 Average Digestibility Coefficients, Daily Balances and Their Standard Errors— Experiment 3 * * * * * « * « * 6 6 Table 16 Analyses of Variance— Experiment 3 F Values • • • • • • 70 LIST OF APPENDIX TABLES Page Table 1 Individual Growth and Feed Consumption Data • • • • * • • 107 Table 2 Coefficients of Apparent Digestibility of Feeds by Individual Animals for each Period— Experiment 1 • • • 108 Table 3 Daily Nitrogen Balances--Experiment 1 . . . • • • • • » • 109 Table 4 Daily Calcium Metabolism— Experiment 1 . . 110 Table 5 Daily Phosphorus Metabolism— Experiment 1 Table 6 Coefficients of Apparent Digestibilities of Feeds by Individual Animals for each Period— Experiment 3 . • * 112 Table 7 Daily Nitrogen Balances— Experiment 3 Table 8 Daily Calcium Metabolism— Experiment Table 9 Daily Phosphorus Metabolism— Experiment 3 . . • 111 . 113 114 ...........115 INTRODUCTION The u3o of milk replaoers in oalf raising is increasing in importanoe* The impetus for the increased attention is provided by the desire to market more milk and the fact that changes in marketing practices make less skiramilk available on the farm* The use of a nutritionally adequate and economical milk replacement in lieu of milk would enable the farmer to raise oalves which otherwise would have to be sold* Down through the years experiment stations and commercial firms have proposed many different milk replacers and feeding programs for the young oalf* However, they either were unsatisfactory from the standpoint of replacing milk nutritionally or they were uneconomical due to the high percentage of dried milk solids and other animal by-products* It is the use of the expensive animal by-products which makes most milk replacers economically prohibitive for the rearing of calves* In the last few years inexpensive vegetable by-products such as soybean oil meal have been used with some degree of success* How­ ever, more information is needed with regard to which vegetable products to use and how to use idiom to the best advantage* It was the purpose of this investigation to study the value of simple milk replacers containing only small amounts of animal by­ products for feeding the young calf* PART I THE USE OF MILK REPLACERS WITH LIMITED WHOLE MILK FOR FEEDING YOUNG CALVES REVIEW OF LITERATURE The nutrient requirements of the young oalf are dependent on the extent of rumen function* At birth the oalf’s rumen is non-functional and the nutrient requirements closely resemble those of monogastrio animals* Milk satisfies these requirements for practioal purposes* Many investigations have been conducted on feeds and combinations of feeds as replacements for whole milk. In general, results with milk replacements have not been equal to those with whole milk* As the rumen becomes functional the nutrient requirements of the oalf become less specific. At this time calves can be weaned from milk or milk sub­ stitutes with substitution of a less refined ration* This review includes discussions on the development of rumen function, weaning age and the use of dried whey and lactose, soybean oil meal, distillers dried solubles and antibiotics in feeding the young oalf* Rumen Development in the Young Calf The relative size of the four stomachs of calves before birth and at full term was studied by Becker and coworkers (1951)* fetal life the rumen is the largest of the four stomachs* In early After about 4 months the abomasum begins to increase rapidly; at 6 months it is equal to the rumen in weight and at full term it weighs twice as much as the other three stomachs combined. According to Parrish and Fountains (1952) activity occurs in the intestinal tract before birth of the calf* -4- This was indicated by the presence of hair in the lower colon and by the relative concentrations of minerals in different parts of the tract* The development of the stomachs after birth has been studied by the slaughter technique* Marshall et al. (1950) observed that between the ages of 7 and 30 days the weight of fresh contents from the abomasum exceeded that of the rumen. According to Schmaltz (1938) in 4-week-old calves the true stomach contains 62 to 66 % of the total stomach contents, the rumen and reticulum 33 to 38$ and the omasum nothing* At 8 weeks of age the true stomach is nearly equal in size to the rumen-reticulum* The rumen-reticulum contains 70$ of the total at 10 to 12 weeks and 84$ at 4 months of age* In a 4- to 12-week-old oalf the omasum contains practically nothing, at 4 months about 2 1* and at 7 months 2*5 to 3 1* Kesler et al* (1951) studied rumen development in calves fed a normal diet of grain, hay and milk* In calves 32 days of age or younger the weight of rumen tissue increased slowly but steadily with age* 32 and 42 days a pronounced increase in weight occurred* Between At approxi­ mately 42 days of age or older, all animals had rumen contents charac­ teristic of an adult ruminant* Their data indicate that, with the feeding regime used, rumen function begins at approximately 52 to 42 days of age* An indirect method of determining rumen development by blood sugar levels has been proposed* An inverse relationship between the glyoemic level and rumen development was first observed by McCandless and Dye (1950)* Craine and Hansen (1952) reported similar results in their work with goats* Further studies by Dye and Orsini (1952) on two male calves indicated that diet influenced this relationship. They observed -6- a poet absorptive glycemia of 90 to 125 mg. per 100 ml. in newborn calves and a rapid decrease during the first month of life. After the first month of life the blood sugar levels decreased more slowly until adult levels of 40 to 60 mg. per 100 ml. were reached. level declined at a slower rate when milk was fed. The blood sugar When a calf was changed from a starter and hay diet to milk, the blood sugar level in­ creased. Later Warner ejfc al. (1953) demonstrated that blood glucose values declined uniformly for all groups until the sixth or seventh week, when the milk and grain groups leveled off at approximately 75 mg. per 100 ml. The hay group declined further and stabilized at 8 weeks at about 55 mg. per 100 ml. Similar results were reported by Conrad et al. (1954). In his work with lambs Reid (1953) found that the major portion of the decrease in blood glucose during the first 4 to 5 weeks was in corpuscle glucose and that plasma glucose later fell to the adult level. Qs concluded from these results that the changes in blood glucose are independent of rumen development and therefore not a measure of it. Another suggested method for measuring rumen development is the level of blood volatile fatty acids. Conrad et al. (1954) reported that in calves on a high roughage ration the volatile fatty acid content of rumen juice increased from an average of 60 meq. per 1. at 4 weeks of age to a maximum of 92 meq. per 1. at approximately 9 weeks of age. A possible relationship between the rate of riboflavin and thiamine synthesis in the rumen and initiation of rumen function was investigated by Conrad and Hibbs (1954). They found a rapid rate of synthesis when the calves were about 3 weeks old. In contrast, Kesler and Knodt (1951) -6- in their investigation of rumen ^nthesis could find no relationship between the age of a calf and the level of certain B-vitamins in the rumen* However, the difference in type of ration fed may have had an influence on the results. In studies reported by McMeekan (1954) calves on pasture began ruminating as early as 7 days and rarely later than 3 weeks* consumption began at this time* Pasture He also reported that grass-fed calves showed better and faster rumen development than milk-fed calves* At 3 months of age a grass-fed calf had a rumen which was proportionately as large as that of an adult cow and relatively larger at 5 months. Digestibility studies showed that 8- to 10-week-old calves fed good quality, leafy, young pasture were able to digest 74.6% of the dry matter* Conrad et^ a l * (I960) reported that 9-week-old calves were able to digest 72% of the dry matter and 82% of the cellulose in grass* Armstrong and coworkers (1954), using 10- to 12-week-old calves reared from birth on pasture and 34 gal. of milk, found digestibility values of 75% for dry matter and 84% for cellulose. The high digestibility of dry matter and cellulose by young calves suggests an advanced stage in rumen development. Pounden and Hibbs (1947) suggested using cud-inoculation for speed­ ing rumen development* In a later experiment Conrad and Hibbs (1953) found that 64.7 to 67*8% of the protein was digested by rumen-inoculated calves compared to 54*4 to 61.8% for uninoculated calves* 1/Vhen an uninoculated calf was later inoculated, the protein digestibility in­ creased from 55*7 to 65*9%. The type of ration fed along with cud- inoculation influenced the establishment of organisms in the rumen and rumen development (Hibbs and Pounden, 1948 j Pounden and Hibbs, 1948). -7- Th© agreement among workers concerning the value of cud-inoculation is not unanimous* Pelissier ©t al* (1964) used 48 calves divided into 2 groups, one of which was inoculated, the other serving as the control* They observed no significant differences in weight gains, heart girth, height at withers, severity or incidence of scours, thriftiness, general appearance or bacterial population in the rumen* McGilliard et al* (1952) also reported no favorable effects due to oud-inoculation* Mann et al. (1954) reported that feeding aureomycin at the rate of 40 to 60 mg* per day to calves results in higher rumen pH and increased size of the rumen* Bacteria and protozoa increased in numbers at an ©curlier age but body growth was not significantly affected* Use of Dried Whey and Laotose An abundance of dried whey and concurrent low price have caused increased interest in its use as a substitute for milk in calf rations. Otis (1905) and Morrison et al. (1922) stated that whey could be used as a satisfactory substitute for milk in calf rations* Calves fed pasteurized skimmed whey and a simple concentrate mixture gained nearly as much as calves fed 10 lb* of skimmilk a day (Morrison et al., 1924)* Later Rupel (1929) conducted an experiment using liquid whey in a ration designed to test the comparative value of white and yellow corn for calf feeding. He found that whey-fed calves made an average daily gain cfl*48 lb. per day compared to 1*72 lb* for skimmilk-fed calves* Hathaway et al* (1943) and Trimberger et al* (1944) also reported satis­ factory results with dried whey as a source of protein in calf rations. In the above mentioned experiments the calves were two to three weeks old at the beginning of the experiment* In tests conducted by Van Poucke et al* (1947) 3- to 4-day-old Holstein oalves were used* They oonoluded that a whey product in combination with vegetable oalf meal produced gains as efficiently as in combination with an animal protein meal* Seekles and Wegelin (1952), using 6 monozygotic twin oalves, studied the effect of removing much of the lactose and salt from whey* They reported no difference in growth between two groups of calves re­ ceiving diets in which 6 and respectively* of the protein originated from whey, A similar result was obtained with piglets receiving up to 30^ of their protein from whey. One of the principle problems in feeding whey is its effect on the incidence of scours* When Wallace et al* (1951) fed rations containing 30, 45 and 60$ dried whey to calves the lower level of dried whey pro­ duced the most rapid gains* with the level of dried whey* They also observed that diarrhea increased Young (1953) likewise observed increased diarrhea when 80^ of the whole milk was repl&oed by whey on an isocaloric basis* To combat the incidence of scours and promote growth Daniel and Harvey (1947) suggested the removal of a considerable portion of the soluble salts from whey by means of dialysis* Brown et al* (1953) proposed the addition of slacked lime (^ teaspoon) to each feeding of reconstituted whey to decrease the incidence of scouring* In contrast. Wise (1941) used dried whey as a remedy for certain types of scours, loss of appetite and general weakness* The treated calves began to improve within five days after initiation of treatment* Since dried whey contains approximately 70% lactose the lactose may be the causative factor in diarrhea* Riggs and Beaty (1947) ob­ served that feeding diets containing 20, 25 and 30% lactose caused diarrhea* They concluded that the lactose linkage was responsible for the diarrhea from feeding rations containing equal parts of glucose and galactose at levels equivalent to 15, 30 and 50% lactose* A year later Rojas et al* (1948) reported that doubling the lactose content of milk caused an increase in urinary galactose* The galactosuria was aecom- panied by diarrhea and unthriftiness of the animals* In a review of the effect of lactose on gastro-intestinal motility Fischer and Sutton (1949) suggested that the effect of lactose in causing diarrhea is by inter­ ference with absorption of water and organic nutrients* A number of workers have shown that lactose lowers the pH of the intestinal tract (Ascroft, 1933; Cannon and McNease, 1923; Kline et al«, 1932; Robinson et al*, 1929; Robinson and Duncan, 1931)* This lower­ ing of the pH of the intestinal tract by lactose is believed to influence calcium utilisation (Fournier, 1954)* He observed that incorporating 12% lactose in a wheat-casein diet prevented bone erosion and negative calcium balance in the lactating rat* Mill et al* (1940) in his work with children found 33*5% more calcium retention when laotose was fed than in its absence* Schantz et _al* (1938) have suggested that galactose affects fat utilization* Richter (1948) alto credited lactose or, specifically, the galactose portion, with increasing the utilization of fat* Although dried whey and lactose can both be used in oalf rations the optimum level appears to be low due to the incidence of diarrhea 10- associated with feeding at higher levels* Flips© et al * (1950) sug­ gested 5 to 10% lactose as being optimum in a semi-synthetic oalf ration. Leighton (1955) reported that the addition of 10% of a fat sub­ stance (Marcol B-75) to a ration containing 35% dried whey prevented scours* Also* the addition of this substance to a diet will stop nu­ tritional soours* In a recent review on the physiological effects of lactose Duncan (1955) concluded that fat and large amounts of Bvitamine can counteract the effects of excessive lactose intake* Use of Calf Gruels Historical* Liebig formulated the first known calf gruel by mix­ ing 3*5 qt* of milk* 3*5 qt* of water* 10 os* of wheat flour* 10 os* of ground malt and 0*25 os* of potassium bicarbonate (Kellner* 1926)* Various modifications of calf gruels using potato starch* malt and wheat or rye feeding meals were proposed by Kellner (1926)* Many ingredients have been used by various workers in their attempt to formulate a gruel to replace all or part of the milk ration* Among the first gruels was that proposed by Morse (1898) who used skimmilk with flaxseed jelly aaded to replace the milk fat* Hayward (1902) reported little difficulty in raising oalves without milk after they were two weeks old* He used a ration composed of 30% wheat flour* 25% cocoa- nut meal* 20% dried skimmilk* 10% linseed oil meal and 2% dried blood* The whole milk fed varied from 74 to 264 lb* per calf* Two years later Lindsey (1904) agreed that calves could be raised successfully on Hayward*s calf meal providing reasonable precautions were taken* Michels (1908) claimed that rolled oats made an excellent sub­ stitute in calf feeding if milk was scarce* However* Savage and Tailby 11- (1909) claimed that skimmilk was the best substitute for whole milk, although healthy oalves could be raised without any milk after the third or fourth week of age* Two years later Savage and Tail by (1911) were able to demonstrate no difference between calves which had been fed skimmilk and those fed substitutes* Krauss et al* (1935) also observed that 2- or 3-year-old heifers raised on dry feed rations were indis­ tinguishable from heifers raised on liquid skimmilk* The use of calf gruels in rearing calves was reported favorably by Lindsey (1915)* However, Bechdel (1917) did not recommend their use for veal production due to inferior carcass quality* For optimum veal production he recommended that an all-milk diet be used* McCandlish (1923) raised two oalves to 150 days of age with milk as the sole ration* He conoluded that milk alone was not an adequate diet for rearing oalves because lack of bulk in the diet arrested the development of the ali­ mentary tract and decreased the digestion of nutrients* This effect would seem to be undesirable in oalves raised as replacements since a well developed rumen would enable the calf to make efficient use of roughages at an earlier age* Soybean type* The soybean oil meal which was first available was of poor quality and had to be improved before its successful use in oalf rations was possible* The first reported use of soybean protein wae by Osborne and Mendel (1917) who found that it had a low biological value* This was confirmed by Hayward et al* (1936)* Ham and Sandstedt (1944) succeeded in extracting a substance from unheated soybeans which retarded trypsin activity in vitro* destroyed by autoolaving* The activity of the substance was Bowman (1944) confirmed these results* 12- La ter Melnick et al, (1946) reported that heat processing also Improved the value of the soybean meal by increasing the availability of methionine* Claudinin et al* (1948) were able to produoe a meal of high nutritive value by processing soybean oil meal in an autoclave at 15 lb* pressure for 4 minutes* However, overheating resulted in a soy­ bean oil meal of low feeding value due to the destruction of lysine and methionine (Claudinin et al*, 1946; Rlesen et al*, 1947; Claudinin et al*, 1947)* The feeding value of unheated soybean oil meal was studied by Shoptaw (1936) on 25- to 70-day-old calves* The calves were unthrifty and had rough hair coats and considerable diarrhea* Wallace et al* (1951) also found that a mixture containing 20% of an unheated 20%-fat soya-flour caused severe diarrhea in calves at about 4 weeks of age* When Williams and Knodt (1950) fed ground raw soybeans at the 40% level, all calves in the groups died* Norton and Eaton (1946) reported good results with calf starters containing 16 to 18% soybean oil meal* The feeding method used was that reported by Savage and Crawford (1935) which allowed 350 lb* of whole milk per calf* The use of soybean oil meal as the main source of protein in calf rations was unsuccessful until a special process soybean flour was developed (Noller and Huffman, 1953)* In this experiment 25% soybean flour was used in a formula containing 10% dried whey as the only animal by-product* calf* The whole milk fed varied from 59 to 89 lb* per Later Stein et al* (1954) and Stein and Knodt (1954) reported the successful use of soybean flour in their milk replacement formulas* Distillers dried solubles* The use of distillers dried solubles in calf rations has not been the subject of extensive research* Davis and Trimberger (1946) first reported satisfactory results with distill­ ers dried solubles in the rations of 2-month-eld calves* Sohabinger and Knodt (1948) in an experiment with 3- to 14-day-old oalves found that distillers dried solubles and distillers dried grains with solubles gave satisfactory results with no effect on palatability* In this experiment 300 lb* of whole milk was fed during the first 45 days of life* Exper­ iments by Slack and Turk (1951) on 107 Holstein calves indicated that normal oalves could be reared on starters containing 10 or 20# distill­ ers dried solubles* About 350 lb* of whole milk was fed during the first 49 deys of life* Lassiter et al* (1953) using 44 Jersey oalves showed that corn or milo distillers dried solubles could replace an equal amount of dried skimmilk in a simple calf starter* were fed hay and 170 to 227 lb* of whole milk per calf* These calves Noller and Huffman (1953) obtained satisfactory weight gains in calves with a calf starter containing 10# distillers dried solubles* The whole milk intake varied form 59 to 89 lb* per calf* Aureomyoln* The effect of antibiotics on the growth of calves was reviewed by Knodt (1953)* The author concluded that auroomyoin, on the basis of reports available, increases growth and decreases the incidence of scours in dairy calves* biotics were variable* The results with the other anti­ A review on antibiotics in animal nutrition was published by Stokstad (1954) and one on the nutritional effects of antibiotics by Jukes and Williams (1953)* -14- Weaning Age The age when oalves should be weaned frcm milk has been the sub­ ject of numerous investigations* Mead et al* (1924) were successful in weaning oalves from whole milk to alfalfa hay and a grain mixture containing no milk at 30 to 40 days of age* from 132 to 508 lb* per oalf* The whole milk fed varied Maynard et al* (1925) obtained similar results with skimmilk or gruel following the feeding of approximately 500 lb* whole milk until the sixth or seventh week of age* Bender and Bartlett (1929) raised oalves satisfactorily on dry grain and hay after weaning them from milk at 30 days of age* Lindsey and Archibald (1931) did not recommend this dry feeding method due to the poor con­ dition of the calves* They were of the opinion that some form of milk should be fed until the oalves were at least 4 months of age* Siting and LaMaster (1934) demonstrated that calves ma y be weaned at 50 to 60 days of age and raised successfully on hay and grain* Ingham et al* (1930) suggested 30 to 60 days as the weaning period* Jones et al* (1931) indicated 30 to 50 days using about 160 lb* of whole milk and 90 lb* of reconstituted skLmmilk* McCandlish (1939) on the basis of his review of the literature suggested a minimum whole milk allowance of at least 400 to 500 lb* spread over the first 4 to 5 weeks* Savage and Crawford (1935) weaned Holstein calves that had re­ ceived 350 lb* of whole milk at 7 weeks of age* They were able to obtain growth above the accepted normal using various experimental mixtures* They concluded that not more than 22# dry skimnilk was necessary in a calf starter mixture. When they tried the Bender and Perry (1930) limited-whole-milk (150 lb.) and blood-flour-ooncentrate 15- mixture method they found that growth of these calves during the first 16 weeks was inferior to those given the 22 % dried skimmilk ration* the end of 26 weeks there was no At difference in weight. Lindsey and Archibald (1925) replaced whole milk with skimmilk at 7 to 10 days of age. They stated that skimmilk substitutes will replace skimmilk adequately. Four years later Lindsey and Archibald (1929) reiterated that dried skimmilk was the best substitute for liquid skim­ milk in raising calves. They also claimed that calf meals were satis­ factory but not adequate for rapid growth. Williams and Bechdel (1931) asserted that a calf starter should contain both dry skimmilk and blood flour. EXPERIMENTAL Selection and Assignment of Animals Twenty-one Holstein calves consisting of 17 bulls and 4 heifers were placed on three milk replacers. The calves were obtained from the university herd and from three looal dairymen. The calves were assigned at random to the various milk replaoers as they became available. A slight adjustment in assigning calves was made with the last calves in order to obtain groups with comparable initial weight. Any calf appar­ ently sick or abnormal during the first few days on experiment was re­ moved and the next animal obtained was substituted in its place. Feeding and Management All calves were left with their dams for 46 hours after birth. They were then removed from their dams, weighed and usually fasted. However, in two cases calves that were hungry were not starved the full 24 hours% they thus received a full feeding the first day. schedule is shown in Table 1. The feeding Milk feeding was limited to a maximum of 56 lb. with the exception of the two calves mentioned above, and was discontinued entirely after the twenty-first day of life. Milk replacer feeding as a gruel at the rate of 0.5 lb. per day and ad libitum in dry form was started on the seventh day of age. fed at any time during the experimental period. No hey was -17 The amount of water fed daily was calculated to supply a total liquid intake of 1 lb* per 10 lb* of body weight* Adjustments were made weekly, if needed, on the basis of body weight changes* No changes in amount of water fed were made if it amounted to less than 2 lb* per day* The calves were kept in individual pens bedded with wood shavings* They were taken off experiment at 60 days of age* Table 1 Daily Feeding Schedule Whole milk Age (days) Replaoer fed as gruel llb.J Replaoer fed dry Ub.; 0-2 with oow — — 3 usually fasted — — 4-6 6 — -- 7-10 4 0*5 ad libitum 11-21 2 0*5 ad libitum 22-60 — 0*5 ad libitum Feed Formulation The formulas of the three milk re placer a used in the experiment are presented in Table 2* Milk replaoer 1 served as the basal ration* Milk replacer 2, which contained 5% dried whey, was used to study the supplementary effect of whey in an all vegetable milk replacement* In milk replacer 3 the 5% dried whey was replaced by 3*5/6 lactose (c*p*) -18- Table 2 Composition of Milk Replacers Ingredients i Milk replaoer 2 3 % % % Fine ground oorn 51*6 47.1 47.1 Soybean flour (52*4?0 33*0 32*5 34*0 Distillers dried solubles 10*0 10*0 10.0 Dried whey — 6*0 — Lactose mm — 3*6 Steamed bonemeal 1*5 1*5 1*8 Calcium, carbonate •5 •5 •3 Salt *5 •5 •5 2*8 2.8 2 .8 *1 *1 •1 100.0 100.0 100.0 Aureof&o* Vitamin and trace mineral** Total ♦ Contained 1*8 gm. Aureamyoin and 1*8 mg* B 12 per lb* ♦♦Mixture oontains: Vitamin A ooncentrate 20,000 U.S.P. units/ gin. 20 ga. Irradiated yeast, 9,000 I.U. Vitamin D/gnu 5 gm. Cobaltous sulfate (Co304*7H20) 3 gnu Cuprio sulfate (CuS04*5H2 0 ) 2 gnu Ferrous sulfate (FeSO^THgO) 11 gm* -19- to dotermine whether the lactose in whey is one of the necessary factor(s)* The protein content of the ration was adjusted by varying the amount of corn and soybean flour* Feed grade aureomycin was added at a level calculated to supply 50 mg* of aureomycin per lb* of feed* The particular product used also supplied 50 meg* of vitamin B^2 activity per lb* of feed* The milk replacers were mixed in 100 lb* lots* The micro ingredi­ ents were premixed, then mixed into a larger quantity before being added to the final mixture* The mixed feed was kept in 30-gallon metal con­ tainers to protect it from moisture and contamination* Measurements of Feed Effects Body weight* The calves were weighed at the beginning of the experiment, two separate days each week during the experiment and at the end of the experiment* All weighings were made at approximately the same time of day* Health and post mortem* The calves were observed daily with par­ ticular note being made of hair coat, condition of feces and alertness of the calf* Three calves were taken to the clinic for post mortem studies after having completed the experiment* Gross inspections were made of the alimentary tract and vital organs* Blood cell counts and hemoglobin determinations were also made on the three calves* Feed consumption and analysis of feed* Daily records of feed consumption by the individual oalves were kept* using the accepted A*0*A*C* (1950) procedures* The feeds were analyzed The results of chemical analyses made on the three milk replaoers are presented in Table 3* -20- Table 3 Chemical Analyses of Milk Replacers Milk replaoer Constituent sT 1 Water (%) 8.11 8.59 8.38 Ash (%) 6.31 6.64 5.92 Crude fiber (%) 2.80 2.80 2.79 Ether extract {%) 5.08 5.07 4.94 Crude protein (%) 26.94 26.69 25.37 N itrogen-free extract (%) 50.76 50.21 52.57 Calcium {%) .874 •884 •788 Phosphorus (%) .790 •804 .736 Copper {%) •0054 .0035 .0050 Iron {%) •0236 •0214 .0233 Potassium (%) 1.10 i.ie 1.06 Magnesium {%) .214 •219 •206 Manganese (%) .0021 .0019 .0019 Cobalt (ppm) 4.27 3.89 3.73 Carotene (ppm) 4.4 4.0 4.6 RESULTS The average whole milk consumption for the three groups of calves varied from 50*7 to 54*9 lb* for the experimental period (Table 4)* The difference was due to refusal of one or more feeds by same calves* Host refusals occurred at the first few feeds following the addition of milk replaoer to the liquid, although in general little or no difficulty was encountered* Table 4 Growth and Feed Consumption Data of Calves to 60 Days of Age Replaoer 1 Z 3 No* of oalves used 7 7 7 No* of calves died 0 0 0 Weight Average initial (lb*) 91*4 93*9 93*6 Average daily gain (lb*) 0*87 0*92 0*87 Standard error of mean (lb*) 0*08 0*05 0*07 fbed consumption per calf Whole milk (lb*) Milk replacer (lb*) Milk replaoer/lb* gain (lb*) 54*9 51*9 50*7 108*2 117*5 112*9 2*21 2*26 2*37 -22- The consumption of milk replacer varied more within groups than between groups. There was no significant difference groups in feed consumption and feed efficiency. between the three However, it was noted that consumption of milk replacer in the dry form was low during the first 20 to 30 days of age. Until such time when feed consumption in­ creased the weight gains were also very low. Growth data are summarized in Table 4 and presented in detail in Appendix Table 1. The average daily weight gains of the calves on milk replacers 1, 2 and 3 were 0.87^.08, 0*92±.05 and 0.87^.07 lb., respec­ tively. Although the average daily gain of the group receiving replacer 2, containing 5% dried whey, was greater than that of the other groups the difference was not statistically significant. The calves in the dried whey group also were the most uniform in weight gains. Growth curves for the three groups of experimental calves and the USDA standard for Holstein calves (Matthews and FohrMan, 1954) presented in Fig. I. are The growth curves show that there is little difference between the three replacer groups in growth over the experi­ mental period. In all three groups the period of rapid weight gain began between 20 and 30 days of age. The calves fed replacer 2, containing dried whey, had the more costive feces, smoother haircoat and more alert appearance. No differ­ ences could be detected between calves on the basal ration and the one containing 3*5^ lactose. None of the calves died while on experiment nor were any calves sick. Slight plaquing and hyperkeratosis were observed in the rumens of the calves upon post mortem examination. values were normal. The blood cell counts and hemoglobin -23' 70 60 Weight gain - lbs. 50 40 30 20 LEGEND “ Replacer I — Replacer 2 ■■ Replacer 3 — USDA standard O 10 20 Fig. I. 30 Days of age Growth curves 40 50 60 DISCUSSION Inspection of the growth data in Table 4 shows that the least vari­ ation occurred in calves fed milk replacer 2, containing 5% dried whey* This is in agreement with previous work of Huffman et al* (1954)* An analysis of the growth ourves in Fig* I indicates a difference in weight gains between the experimental calves and the USDA standard (Matthews and Fohraan, 1954) during the first 20 to 30 days of age* During this period the experimental calves gained an average of 8 to 10 lb* each compared to 22 lb* for calves on the USDA standard* Be­ tween 30 and 60 days the growth rates of the oalves were equal* The first 20 to 30 days of life is referred to as the "critical period"• During this period the weight ohange of the experimental oalves was negligible* This is in marked contrast with the continued increase in weight gains in the USDA standard* The standard was es­ tablished with oalves fed whole milk to 4 weeks of age followed by skimmilk to 6 months of age* In contrast, the experimental oalves were fed a total of 50*7 to 54*9 lb* of whole milk each* The results indicate that the calves were unable to utilize the milk replacers satisfactorily during the first 30 days, although, after 30 days the growth curves of the oalves fed replacers were parallel to that of the USDA standard* Similar results were reported by Stein et ed* (1954) who obtained less growth when milk was replaced by milk replacers at 10 days of age* -25- The data indicate the necessity of feeding milk to prevent this period of little growth* However, Savage and Tailby (1911) and Krauss at al* (1935) reported that they could not distinguish between 2- or 3-year-old heifers which had been reared on large amounts of milk as compared to limited milk* This indicated that the critical period had a negligible effect as far as the mature animal was concerned provided a normal ration was fed after the experiment was completed* The consumption of feed was closely related to the rate of growth* It was noted that during the first 20 to 30 days of age, when the growth rate was either nil or very low, replacer consumption was about one pound per day or less* The growth curves indicate that only enough milk replacer was consumed to satisfy the maintenance requirement of the calf* At approximately 25 days of age a rapid increase in feed consumption occurred and by 60 days of age the consumption was approx­ imately 4 to 5 lb* per calf daily* The increase in feed consumption was also reflected by increased weight gain* The calves with the lowest average daily gains were those which did not increase their feed con­ sumption until about 40 days of age* Although they were gaining weight rapidly at the end of the experiment the weight gains for the experi­ mental period were less than the USDA standard* At the same time that weight gains and feed consumption increased there was a marked change in the condition of the feces* Before the change occurred the odor and appearance of the feces were typical of a oalf and afterwards more representative of those of a cow* This in­ dicates that a physiological change may have occurred due to increased rumen function* It is postulated that the end of the critical period -26- ooincides with tha beginning of rumen function as Indicated by tha change in odor of rumen contents (Kesler et al*, 1951) and the decrease in blood sugar (Craina and Hansen, 1952; McCandless and Dye, I960)* The most noticeable effects observed when dried whey was included in the ration were improved fecal condition, alertness and improved hairooat* It is possible that the effect of dried whey is mediated through the intestinal flora as evidenced by the improved condition of the feces* In replacer 3, the 5% dried whey was replaced with 3.5^ lactose to determine whether or the favorable effects* not the lactose in whey was the factor producing An inspection of the data indicates that 3*5% lactose in the vegetable milk replacer used in this study had no effect on weight gains or condition of the calf* 1 and 3 were similar in all respects* Results with milk replacers However, calves on both milk replacers 1 and 3 were less satisfactory than 2 in general appearance and condition of the feces* Although the feces of calves on milk replacer 1 and 3 were less costive than those of oalves on milk replaoer 2, there was no evidence of diarrhea as had been reported by Wallace et al* (1951) who used higher levels of lactose* The results in this experiment do not agree with those of Flipse et al* (1950) who reported a favorable effect with 5% laotose in a synthetic milk ration* The different results may be due to the types of rations fed* The data indicate that a ration containing a special process soybean flour can produce satisfactory results in calf formulas* Al­ though the method of processing used is not available it is probable that the availability of the protein was increased by a process similar -27 to that proposed by Claudinin at al* (1948) which inoreases the availa­ bility of tha amino acids, methionine and lysine* Tha ixnportanoe of processing was demonstrated by Holler and Huffman (1953) who found that oalves reared on a milk replacer containing sol­ vent extracted soybean oil meal had a longer critical period than calves reared on a milk replacer containing a special process soybean flour* The odor of the feoes was less offensive after the critical period in­ dicating that a change in the utilization of food had occurred* Carroll et al* (1952,1953) reported that in raw soybean meal the nitrogen passes farther down the intestinal tract before absorption than in the case of heated meal* The passage of the unabsorbed protein into the large intestine can result in "putrefaction" of protein* According to Schmidt (1907) this occurs exclusively in the large intestine* The absence of putrefaction would indicate absorption of the protein in the small in­ testine due either to an increase in the ability of the calf to utilize it or to a treatment which increased the availability of the soybean protein* The milk repl&cers oontaining 10% distillers dried solubles pro­ duced better results than those reported by Huffman et al* (1954)* How­ ever, in the present experiment the distillers solubles were a blend mixture compared to the single product used in the previous experiment* The milk repl&cers used in this study also differ from those used pre­ viously in type and amount of antitiotio* The rations used in the pre­ sent investigation contained 50 mg* of aureomyoin per pound of feed while the rations reported by Huffman et al* (1954) contained 10 mg* of bacitracin per pound of feed* The improvement in the present rations 28- oould be due to the effect of aureomycin* Knodt and Ross (id52) and Rusoff et al* (1951) reported increased growth with aureomycin in the diet* The results of the blood cell counts and hemoglobin determinations indicate that the milk repl&cers contain sufficient blood forming con­ stituents* Also, disease did not appear to be a factor as evidenced by normal differential white cell counts* SUMMARY Twenty-one Holstein oalves were placed on three milk replacers-bas&l, basal with &% dried whey and basal with 3*5^ lactose* The calves were started on experiment at 3 days of age and taken off experiment at 60 days of age* The average whole milk consumption for the three groups of calves was 54*9, 51*9 and 50*7 lb*, respectively, for the experimental period* form* Milk replacers were fed both as a gruel and ad libitum in dry No hay was fed during the experiment* The average daily gains of the calves on the basal, whey and lactose rations were 0*87f*08, 0*92^*05 and 0.87ir*07 lb*, respectively* The differences were not statistically significant. Growth patterns indicated the existence of a critical period in the life of the young calf from birth to approximately 25 days of age. The end of the oritical period was characterized by increased growth, increased feed consumption and improved appearance of the calf* Calves receiving the whey ration had the more costive feces, smoother halrcoat and were more alert* The use of lactose appeared to have no benefit under the conditions of this experiment* PART II DIGESTIBILITY AND BALANCE STUDIES WITH MILK AND MILK REPLACERS REVIEW OF LITERATURE The Nutritive Value of Milk Effeot of processing* Among the many methods of food processing, heat has been widely employed* Food treated in this way must retain its palatability as well as most of its nutrients* It is generally known that the denaturation temperature varies with different proteins and the rate of denaturation increases with increase in temperature* The effect of heat on the nutritive^ value and digestibility of various milks has been studied by a number of investigators* Among these were McCollum and Davis (1915) who observed a decrease in the nutritive value of protein when autoclaved milk was fed to rats* Whole and evaporated milk were compared by Nevens and Shaw (1932) in a paired feeding experiment with albino rats* The mean of 47 coefficients of protein digestibility for whole milk was 92*3 and the mean of 45 co­ efficients for evaporated milk was 88*4* A year later the same authors (1933a) were unable to find a significant difference in the apparent protein digestibility of two kinds of powdered milk but a significantly higher value was obtained for fresh whole milk* Fairbanks and Mitohell (1935) found that preheating in the spray-drying process lowered the biological value of the protein about &%, although the digestibility of the milk protein was not significantly affected* Raising the temperature to scorching decreased the biological value further and lowered the digestibility at a rate which increased with the degree of scorching* -32- Honry and Kon (1938) used pairs of littermate female rats starting at 24 to 25 days of age to determine the biological value and true digest­ ibility of raw and commercially sterilized milk* The biological values of raw and sterilized milk proteins were 84*3 and 79*1, respectively* The true digestibility of the proteins was 96*4 and 95.3^, respectively* "When Anderson et al* (1940) fed raw milk to dogs they grew well and had normal reproductive functions* pasteurized and evaporated milk. Poor results were observed with both In an experiment with kids, Catel (1932) reported improved growth and utilization of fat, protein and carbohydrate with raw goat milk as compared to pasteurized goat milk* Cook et al* (1951b) observed that sterilization of milk decreased the growth of rats* They conoluded that the degree of decrease in protein efficiency of the milk was in proportion to the severity of heat treatment and holding time* Although some investigators reported decreases in the nutritive value of milk due to heat others were unable to substantiate these de­ creases* In an experiment with rats, Henry et al* (1939) were unable to demonstrate a significant difference in the biologioal value of the protein in spray dried, roller dried and evaporated milk. However, in this experiment, the evaporated milk was significantly less digestible than the spray-dried milk* A comparison of the nutritive value of un- heated and autoclaved skimmilk in dogs and rats by Kraft and Morgan (1951) indicated that autoclaving had no effect on nitrogen retention in dogs, but in weanling rats the milk lost one-half to two-thirds of its growth efficiency. This dissimilarity in speoies is not in agree­ ment with Schroeder et al. (1953) who state that the conflicting claims -33- regarding the deleterious effect of heat oannot be attributed to the difference in species of experimental animals used. Rather, the vari­ ation in nutritive value of the milk is due to both the intensity and duration of heating* Henry et; al* (1937) oould demonstrate no difference in the biologioal value and true digestibility between the proteins of raw and pas­ teurized milk* Hodson (1952), using the rat repletion method of protein evaluation, oonoluded that sterilization of evaporated milk did not affect the nutritive value of the protein* TUhitaah (1943), using rats, and Sohroeder et al* (1953), using dogs, also could find no nutritional difference between evaporated and fresh raw milk* Since it was noted that heat may affect the nutritive value and digestibility of milk protein, the next step was to determine the mode of its action on the milk protein* Hodson (1954) suggested that for rat growth the amino acid deficiencies in evaporated milk proteins in­ volved primarily the sulfur-containing amino acids* The effect on biological value of supplementing heat treated milk proteins with cystine and methionine was studied by Henry and Kon (1953)* They found that the addition of 0*2/4 cystine increased the biological value of the milk proteins 5^, further addition of 0*4/4 DL-methionine increased the biological value another 5/4* Methionine alone had the same effect as a combination of methionine and cystine* Numerous investigators have studied the mode of action of heat on milk proteins* Block and Mitchell (1946) suggested that heating casein formed a peptide linkage between the epsilon-amino group of lysine and the free carboxyl group of one of the dioarboxylio amino acids* This -34- oomplex was resistant to enzymatic digestion. Pader et al. (1948) showed that overheating of casein decreased the rate of lysine liberation. They indicated that the lysine may have been bound to other amino acids by a linkage which was unavailable to enzymes. The slow liberation indicated that the low biological value of lysine was not due to destruction but only to rate of availability. In experiments on the effect of heat treatment of milk, Cook et al. (1951a) found a significant decrease in protein efficiency of lactalbumin for rat growth when lactose was contained in the heat treated sample. the heat treatment had no effect. In the absence of lactose They observed no browning in heated lactose-free samples but a deep caramel color in samples containing lactose• Significant changes in the nitrogen distribution of sterilized milk were reported by Menefee et al. (1941) and Shahani and Sommer (1951). These changes occurred as a result of the coagulation of albumin and globulin which freed the amino groups. The free amino groups were then capable of combining with sugar to form a protein-sugar complex. The formation of the protein-sugar complex was followed by Henry et al. (1948) using the Van Slyke method for free amino nitrogen. In their experiments they could account for the loss of one molecule of lactose for each free amino group destroyed. Maillard (1912) first pointed out a reaction between the amino group of the amino acid and the carbonyl group of a sugar. Hill and Patton (1947) and Patton and Hill (1948) demonstrated that the delete­ rious effect of heat processing on the nutritive value of milk proteins may be due to the Maillard reaction. Henry e^t _al. (1948) attributed 35- mueh of the reduction in biological value of protoin to the combination of lysine with lactose* lfllhen Mclrxroy et al* (1949) autool&Yed ease in in the presence of dextroset the casein did not support the growth of weanling albino rats* Similar treatment in the absence of dextrose had only a slight effect on the growth-promoting ability of casein* Schroeder et al * (1951) observed a decrease in nutritive efficiency of protein by 66 to 77% relative to the unheated protein when it was auto­ clave d in the presence of equimolar concentrations of lactose, maltose9 xylose, or fructose* Shipstead and Tarassuk (1953) reported that browning was unlikely if the moisture content of milk was below was low* and the storage temperature The effect of browning andits associated changes in milk has been reviewed by Patton (1955)* Certain vitamins are known to be heat labile* The use of heat in milk processing would be expected to lower the vitamin content of the processed milk* Kon (1938) reported a marked decrease in the ascorbic acid oontent of milk by commercial sterilization* Sterilisation of milk also caused a 30^ destruction of the thiamine in the milk* The destruc­ tion of vitamin A and carotene by sterilization of milk was negligible (Gillam et al.# 1938)* The heat lability of pyridoxin® in milk was determined by Tamarelli et al* (1955) using a microbiological assay and rat growth procedure* Heat destroyed much of the vitamin and decreased the biological response to the remaining vitamin* Effect of storage. The effect of storage on the nutritive value of dried skimmilk was investigated by Henry and Kon (1945)* They ob­ served that prolonged storage decreased the biological value but had no 36- effect on the true digestibility# The biological value of spray-dried skimmilk decreased from 88 #5 at 18 months after manufacture to 71 #1 sane 36 months later (Henry et al., 1946)# Marked losses of arginine, histidine, lysine and methionine in discolored dried skiinmilk samples were observed by Hodson and Krueger (1947), Samples which retained their white color lost only minor amounts of the amino acids# Henry and Kon (1948) attributed the decrease in nutritive value of dried skimmilk to the presence of moisture# They observed that on the addition of lysine to the experimental milk sample the biologioal value of the protein was equal to that of the control sample# The storage of evaporated milk for 16 months at room temperature had no effect on the nutritive value of the protein (Hodson, 1962)# However, storage for 5 years resulted in considerable loss of the nutri­ tive value of the protein# Schroeder et ^al# (1953) reported that the digestibility and biological value of the milk proteins were not affected when milk was kept in frozen storage for 5 months# The losses of seventeen ami.no acids in evaporated milk stored for long periods were studied by Hodson (1960)# During 5 years of storage the milk lost 17% of the lysine, 17% of the histidine and 11% of the arginine# During the first 15 to 17 months the losses of the three amino acids were less than 4j£# Webb ejb <— s »H CO CR r-l © o o is go aS 0 o o> a £ pa* w © XI £4) 3 w o o •HI pa • a> 8 03 03 3| ■PI «l S * ■ 4 * © H o> «i ■g o XI 5 (0 •H u § 8 iH 00 pq • o o M § -* H XI co o» 1 cr as 4 Ii H H o o o CM CO as CO 03 iH t4< JH O 4» . CM to Ui 03 9 13 <£ to 3 CM tO o> rH « a rH £ sS o • co> to • t03 o• to» to e- • CO CO f• to <4» * o> CO a o to I fr» • 03 03 • GO 03 CM • lO CM • to to • to O 03 • CO CO CO • CO • co 1 1 1 1 • CO 03 CO • lO 03 to • co to to • 00 c• to • 03 to o O • 03 03 • 03 03 •rf Xi 3(0 o_, •H Hi o o 03 03 03 03 03 • ■4* 03 60 • CO 03 CO • to 03 I© • o • CO 03 1 1 1 ■ • CO 03 03 03 CM * ■4* 03 o • LO 03 CO • c— 03 • 1© 03 to -4» • • CM 03 CO c*• 4* 03 CM • 60 03 co -p d < D £ a< *5* S w. co 03 TJ TJ H H 0 O * S W© to © > H © O CO > H i—1 02 © o w 5* TJ 03 © -*t > H H 1 at (O o to % r-i as o IQ £ r-f © O © g pH © O -P HQ *d £ J4 t ® o © t© •rf Q* m © o « a 5s H H 1 © rH O u <0 • * § o 0 •H P* © bO •H P< © m -P -P © © u U h ** © I O © 44 *3 44 a* rH S-) O rH ■H B •H © B o2* © > H © O -39- b- to 0> ct •31 Si -P Si © Apparent ut 2 u o Pe« OS • ‘p os e oft. a Digestibility of Various Feeds & (U o „ ^ t t T< •H © d .d o CO O • CO CO o• to rH to o OS rH W JC o 9 9 CO • O OS 1 1 os • S&. to to O • BO CO o• o co rH • &£. pH b- o• o• CO CO (O o• b• to CO • 5?-OS O -P -P 9 O to •M* CD 9 rH -P P 9 O 40 tO os ■31 as rH u 9 H o> rH y^s b- cos 8 o rH OS 9 pH P -P 9 O rH w U 9 nO •H 9 Cl jS o CO •31 Si <0 © rO *4 o Pu O * OS rH CO • co co ao • 00 BO o o• OS • o • LO t- o• b- 00 o to CO CO CVS • o• to OS 9* t*» 1 1 CM • CO CO CO • to CO O • CO CO Q-* a s *3 t* T* n >4 o o w o o Pt4 to as u bO d p o o I -a tt o 9 oo 0 b~ • rH OS Jt $ a o -P •I a 9 ,a (4 e• o• rH OS rH OS ld CM • OS • IQ 9* pH • CM rH • rH b- CM • LO • os 00 iQ CM • O OS b• ao CO CO • H* • UQ CO CO -31 o P«< • co CO rH I 60 • CO CO

s © o os 00 co -p p p 4> at o 9 • os 00 9 • CM OS l i iQ • o CO to0 to • o t— 00 pH • LO OS OS • to CO co 1 1 o• os CO • co CO CO • oo IQ • 00 CO co O J.5 -p Of P« 9 -C Ou 9 o O rH • CO os CO © to • os 9 A9 at at § d •H 9 la t*D as d e o o W> o o 5 9 U h0 d •H 9 la bfl a t* o o o o •H P O © H CJ rH 9 © e p« £» O CO rH O •rt s$ ° d © *H *9 ° >» a o CO •H *H O pH •H (4 O 9 33 OO d Ih 9 8 >- 9 O CO CO rH •rH O £3 9 9 JO >S O CO pH •rt O d 9 9 >» O CO rH »rl o d o CO -40- • o a • u <25 £ Tabl<® 6 (continued) M CM o to a> rH eo 03 rH f © O d o td l o d o td rcJ TO d © bO d •H H V« © ttO d bQ P d • o o• o LO Cm 0> o> «l 03 P •H ja o rO jS •H §) o 3 9 a 3 w 4 cO 00 to to co 00 o> o to H< to b- 00 o 00 oo co © -P P © O © co CM CO CO CM o> ■3! a

o o • 00 CM <* © ttO o O CJi u iO • H* o& Lf> © •rl rH a Cm CO o si <5 3 rH •H lO 00 b- is> o> LO rH o> c*» b- LO CM CO o CO b- CO • 00 CO a 00 co o> CO I b> o> CJ> CM CO b- co co • H* to 00 00 t- e- b- 'd rH •H 3 -P to •d © © Cm o d © P© > » o co d at © 'S* o CO © rH a P P © O T* to tJ d © *H •rl o •H d d © t s % >* •d n w © t o rH d P d © d 3 rH rH rH O d •H t o Vi P © •rl Q O O d © C o © » u © © rH rH P rH 3 •H H P o © w •rl Q O © • © M t> o> o rH 0 GS • ® ■8 5 * d 01 o d © V. w V* © rH rH •rl © « rH © TO © © P 3 rH P O © © •H Q © CO rH © O o O O 41- A cross section of digestibility coefficients obtained for various concentrates with cattle, sheep and swine is presented in Table 6* Due to a pauci-ty of values for calves it is impossible to TnAVfi a direct oghw parison. The results of a digestion trial by Archibald (1928) with 9- month-old calves fed calf meals are presented in Table 6. The coeffi­ cients for the calf meals were lower than those obtained on the other feeds using older cattle, sheep or swine with the exception of the ether extract which was more digestible in the calf meal* The use of filled milks in digestibility trials with calves was reported by DeMan (1951)* He found that soybean oil, hydrogenated soy­ bean oil and whole milk fat were 67, 75 and 96$ digested* Again it demonstrates the higher digestibility of milk fat in comparison to vegetable fat* A beneficial effect was also noted by Jacobson et al* (1949) and Jarvis and Waugh (1949) when hydrogenated soybean oil was fed to calves in the place of regular soybean oil An investigation of the utilisation of nitrogen from pea-, rye-, and soya-flours and milk by the rat, pig, dog and rabbit was conducted by Lelu (1934)* The results obtained with milk on the rabbit were vari­ able; by the pig, dog and rat it was 96$ utilised* The utilization of the flours was highest by the pig (90-96); intermediate by the dog (7181), and lowest by the rat (66-77)* Bondi and Birk (1952) reported that the addition of trichloracetic acid to pancreatic digests of plant pro­ tein feeds resulted in the formation of considerable precipitate* This did not occur with animal protein feeds* Garrigus and Mitchell (1935) studied the effect on digestibili'ty of grinding corn for pigs. Their results indicated a 13$ increase in 42- protein digestibility due to grinding, Heupke and Marx (1928) observed that the cells of the nut had to be destroyed or mechanically ruptured before fat was digested in the small intestine of m ice« A similar result was also observed in man. Carpenter (1951) concluded from his summary of rat data that the animal proteins were nutritionally superior to the vegetable proteins. He found that soybean oil meal was the only vegetable protein within the range of the animal proteins, Desikackar et al, (1946) reported that the biological value of cow's milk and soya milk was the same for the adult rat. The animal and vegetable feeds have the same general biolog­ ical value for the ruminant (MeNaught and Smith, 1947), The effect of level of feeding on the digestibility and biological value of a feed was studied by Mitchell et al, (1932), They found that the lowest level of feeding used in a steer was associated with the most oomplete digestibility of all nutrients. Digestion in the Young Calf When the calf is b o m the milk it consumes passes directly into the omasum and abomasum via the esophageal groove. As the calf becomes older the use of the esophageal groove diminishes. The function of the esophageal groove in the young calf and adult animal was studied by Schalk and Amadon (1928), They reported that, during drinking, the water spurts from the oardia and is deposited in the front of the rumen and is later transferred to other parts of the rumen. They observed that water does not follow the esophageal groove into the omasum and abomasum and concluded that the esophageal groove functions only in the nursing calf. -43 Trautmann and Schmitt (1933) studied the passage of milk into the stomach in young goats fed a diet of milk and water* Swallowing was necessary for entrance of liquids into the esophageal groove* They also observed that the goat lost its ability to use the esophageal groove after weaning and the start of roughage consumption* Wise ejt ed* (1942) reported that elevation of the neck was not a significant factor in promoting milk passage through the esophageal groove. Espe and Cannon (1937) established that the psychic phase of gastric secretion was absent or of minor importance in calves. The changes pro-, duoed in consumed milk prior to its entrance into the stomach of the calf were studied by Wise ot al. (1940) using "sham feeding"* They found an increase in rate of rennet coagulation, curd tension, hydrogen-ion con­ centration, lipolytic activity and cream volume. The effect of curd tension on the digestibility of milk was studied by Espe and Dye (1932). In an adult dog, milk of low curd tension left the stomach in 1.7 to 1.8 hr. and a milk with a high curd tension took 2.3 to 2*8 hr. In a calf it took 4.0 hr. for milk with a low curd tension to leave the stomach as compared to 6*0 hr* for high curd tension milk* Doubling the curd tension of the milk increased the digestive period 30 to 65%* According to Espe and Cannon (1935) milk containing up to 6% fat tended to leave the stomach faster than skimmilk. Mortenson et al. (1935) reported that boiled milk left the abomasum of a calf faster than raw milk. The inability of the young calf to utilize starch was demonstrated by Shaw et al. (1918). Calves at 4 to 7 days of age were able to digest only one-fifth of the starch consumed. At 3 to 4 weeks of age the calves -44- were able to digest well over 90% of the starch in the ration. It seems that the meager ability of the calf to utilize starch at 4 to 7 days of age may be attributed to a shortage of starch-splitting enzymes. The increased efficiency of starch digestion at 3 to 4 weeks of age might be attributed to enzymes other than those in saliva. Dukes (1947) reported that the saliva of cattle does not contain an amylase. The inability of the calf to utilize starch has stimulated the use of malt, containing the enzyme diastase, to help the calf digest the starch. Kellner (1926) credited Leibig with using wheat flour treated with malt in feeding calves. malt. Kellner also described calf rations using Hittcher (1909) reported the use of starch treated with malt te replace the butterfat in calf feeding. were kept on experiment for 15 weeks. He used 7-day-old calves which Although 15% of the calves died while on experiment he reported that calves fed starch treated with malt were slightly better the first 4 weeks of the experiment. Remer (1932) reported calf rearing experiments with dried potatoes supplemented with distillery malt. He observed no detrimental effects when feeding was commenced the first week and gradually increased to 400 gm* per head daily. Minz and Schilf (1932) conducted experiments with rats fed by stomach tube and killed after one hour. of digestion were determined. The nature of the clot and degree They noted finer milk curd and a greater degree of digestion when malt preparations and extract of dried malt were fed to rats than when no malt was fed* Pancreatin and papain concentrates have also been used in attempts to aid the calf in digesting feed. Conquest et al. (1938) produced an 45- enzyme- treated milk which did not stay in the stomach as long as un­ treated milk* The calves were fed colored milk, killed after 7 hours and the amount of curd remaining in the stomach was determined* The calves fed normal milk retained ZZ% more curd in the stomach than calves receiving treated milk* Also the curd tension of the untreated milk was twice that of the enzyme-treated ourd* The use of papain and pancreatin powder in calf replacement feeds was reported by Williams and Knodt (1951)* The addition of papain or pancreatin powder resulted in poor growth and low feed consumption* Post-mortem examination of the two fatalities which occurred indicated dehydration and intestinal degeneration* A study of the fat content of the feces of 14 calves was made by Howe. (1931)* During the first three days of life a readjustment in the metabolic activities of the calf was noted* He reported fairly complete digestion of the fat but a failure in absorption* He also found that the percentage of neutral fat decreased and the free fatty acids in­ creased during the first week of life* Nitrogen Metabolism The quality of the protein in the diet of the young calf is very important before the rumen becomes functionally developed* Although the nitrogen in the ration may be adequate, the amount of food protein re­ quired depends on the amino acid composition of the protein and the relative availability of the amino acids* As the rumen develops, the quality of food protein required decreases due to synthesis of high quality protein by the rumen microorganisms* The effect of a nitrogen-free diet on the digestibility of the various nutrients by oalves was studied by Blaxter and Wood (1961a)* 46- They found that as the digestibility coefficients of the dry matter decreased from 94.0 to 77.0 those of the dietary fat decreased from 91.7 to 44.9. The endogenous urinary nitrogen, which represented the minimum requirement for maintenance of nitrogen equilibrium, was 81,9 mg. per kg. body weight per day. It was noted that the output of urea plus ammonia decreased on a nitrogen-free diet. Later Blaxter and Wood (1951b) demonstrated that the metabolism of a calf on a starvation diet differed from that of a calf on a nitrogen-free diet. The effeet of a sparing action by the nitrogen diet was shown by the increased urea plus ammonia excretion of calves on the starvation regime where the loss of urinary nitrogen was 250 mg. per kg. body weight. The authors pointed out that this was much greater than the value of 152 mg. in sheep (Morris and Ray, 1939), 162 mg. in the goat (Morris and Ray, 1939) and 90 mg. in the cow (Hutchinson and Morris, 1936; Morris and Ray, 1939). In another experiment Blaxter and Wood (1951c) observed that urinary nitrogen increased at a constant rate with increasing intake of apparently digested nitrogen. protein in the diet. This was irrespective of the amount of The feeding of a lower level of protein increased the biological value of the protein. The decrease in biological value with the higher intakes of protein was attributed to the use of the protein for energy with the result that less nitrogen was retained in the tissues. At comparable intakes of energy the storage of nitrogen was greater for the diet high in protein. In a study of the value of cow’s milk Blaxter and Wood (1952a) observed that body weight gain and nitrogen storage were linearly related to the intake of milk. urinary nitrogen did not change with milk intake. The excretion of The biological value 47- inoreased with increased intake even at the higher levels* The calf with the higher basal metabolism stored about 40 percent less nitrogen* The increased loss of nitrogen could be accounted for by the increased excretion of urea-, ammonia- and amino-nitrogen. Blaxter and Wood (1952b) also conducted experiments with 4 calves given dried skimmilk, casein or gelatin as the sole source of protein* The calves were in positive nitrogen balance with the dried skimmilk and casein and in negative balance with the gelatin* changes* The nitrogen balance was correlated with body weight The biological value was 92*3 for dried skimmilk, 78.8 for casein and 29*5 for gelatin* These results were comparable to the biolog­ ical value in the calf, rat and man when the skimmilk was taken as 100* Carr et al* (1917) studied the effect of 5 different rations on the nitrogen retention of calves* They found that skimmilk gave the best results while a vegetable meal and vegetable-dried blood meal produced the poorest results* Lofgreen et a l * (1951) in their studies with calves observed an increase in biologioal value when the energy content of the ration was increased by the addition of non-nitrogenous feeds* Forbes and Yoke (1955) studied the effect of energy intake on biological value of the protein fed to rats* They observed that low levels of food intake de­ pressed the biological value of the protein due to the increased use of the dietary protein for energy* The effeot of energy intake on protein utilisation has been studied in man (Werner, 1948), the mouse (Bosshardt et al*, 1946), the rat (Barnes and Bosshardt, 1946) and the dog (Allison ^^t al «, 1946 ) • The field of carbohydrates and fats as they influenced protein utilisation and metabolism in animals and man, was surveyed by Munro (1951)* 48- He presented evidence that carbohydrates played a role In promoting utilization of dietary protein and also that nitrogen balance was affected by energy intake* He indicated that the feeding of carbohydrates to fasting animals reduced nitrogen output, but the feeding of fats had no effect until the fat stores were exhausted* taining 20 and 28$ protein to chicks* best results* Sunde (1955) fed diets con­ The 20$ protein diet produced the Addition of 5 to 10$ fat to the 28$ protein diet pro- duoed comparable results* The author suggested that high levels of protein are detrimental to ihe chick unless accompanied by high levels of energy* A value for metabolic nitrogen excretion of 0*45 gm* per 100 gm* dry matter intake was obtained by Hutchinson and Morris (1936)* This value was obtained in experiments performed on goats, sheep and cows using a low nitrogen diet* Blaxter and Wood (1951a) obtained a value of 0*43 gm* which is in close agreement with Hutchinson and Morris (1936)* A much lower value was reported by Lofgreen and Kleiber (1953) who ar­ rived at a figure of 0*27 gm* per 100 gm* dry matter intake* They claim that their value is valid because it was determined under conditions of normal intake of protein and total energy* From a study on the effect of fiber on the utilization of dietary protein by rats Rutherford and Crampton (1955) concluded that the source as well as the amount of fiber influenced the apparent digestibility of protein* Calcium and Phosphorus Metabolism The importance of calcium and phosphorus for the young growing calf is indicated by the fact that about 70$ of the body ash consists of these - two elements* 49 - Approximately 99$ of the calcium and 80$ of the phosphorus in the body are present in the bones and teeth* Blaxter and Wood (1952a) determined that the storage of calcium and phosphorus in the young calf was linearly related to the amount of milk ingested* At an intake of 2*5 times maintenance 92$ of the milk calcium and 80$ of the milk phosphorus were retained in the tissues* Archibald and Bennett (1935) found that the retention of phosphorus was greater when dairy heifers had an intake of 3*25 gm* than on 1*8 gm* per 100 lb* body weight* According to Huffman et al* (1933) 10 to. 21 gm* of phos­ phorus daily met the requirements of cattle from 18 months to first calving* They also indicated that 6 to 12 gm* calcium daily met the calcium requirement of a calf from birth to 2 years of age* Ellenberger et al* (1951) slaughtered 16 calves at 90 days of age which had gained 139*6 lb* from birth to time of slaughter* The calves ate an average of 6*63 gm* calcium and 5*71 gm* of phosphorus per 100 lb* body weight daily* They utilized 47*8$ of the calcium and 36*9$ of the phosphorus* The calcium and phosphorus content of their bodies were normal* Assuming 50$ utilization* the authors suggested a minimum allowance of 6*32 gm* * calcium end 4*20 gm* phosphorus per 100 lb* body weight daily* The National Research Council (1950) recommended 8 gm* calcium and 6 gm* phosphorus daily for a 100 lb* growing calf* Converse (1954) determined the oalcium requirement as being 7*7 to 7*2 gm* daily from birth to 6 months of age for 4 Holstein and 4 Jersey calves* respectively* He reported that this amount of calcium was adequate for growth but not for gestation* of hay fed* It may have been affected by the abnormally small amount 60- The oalolum maintenance requirement of the bovine was determined by Hansard (1954) using radioactive calcium* He determined that the maintenance requirement per 100 lb* body weight for calcium inoreased from 0*5 gm* at 10 days of age to 2 gm* at 6 months of age* From 6 months of age to maturity it remained relatively constant* Blackwood et al* (1936) working with calves and Las by and Palmer (1935) with rats concluded that there was no difference in caloium and phosphorus retention between rations of raw and pasteurised milk* Willard and Blunt (1927) in experiments with children observed more favorable results with evaporated than pasteurized milk* Causeret (1953) noted decreased calcium retention with increased water consumption* Fat intake apparently has no effect on calcium retention (Fuqua and Patton, 1953)* Lactose appears to increase oalcium retention in the rat (Outhouse et al*, 1935; Fournier, 1954) and glucose has no effect (Sohreier and Mechtold, 1952)* EXPERIMENTAL PROCEDURE Experimental Design Three experiments were conducted in this investigation* A 4 x 4 Latin square consisting of 4 animals, 4 periods and 4 treatments was used in experiments 1 and 3* The design of experiments 1 and 3 and the ages of the calves at the time of each fecal and urine collection are shown in Tables 7 and 8* In experiment 1, 5-day preliminary periods and 2-day collection periods were used* In experiment 3, the preliminary periods consisted of 4 days and the collection periods 4 days* Experi­ ment 2 consisted of two calves on continuous 2-day collection periods* The 2-day values were combined into 4-day periods on the basis of calf age* The calf on raw whole milk was placed on experiment at 8 days of age but developed diarrhea and had to be removed from the experiment temporarily at 10 days of age* It was placed on experiment again at 14 days of age but at 26 days it again had to be removed due to diarrhea* The calf fed evaporated milk was placed on experiment at 10 days of age and taken off experiment at 32 days of age* Selection and Assignment of Calves Ten male calves were used in the three experiments* The 4 calves in experiment 1 consisted of two Holsteins, one Guernsey and one Ayrshire* In experiments 2 and 3 only Holstein calves were used* The calves were obtained from the university herd and local farmers when 2 to 4 days of -52 ago and assigned to the experiment randomly* A calf whioh was sick or refused to eat was removed from the experiment and the next calf sub­ stituted in its place* Any data oollected on calves taken off experiment were discarded* Feeding and Management The calves were placed in individual pens on heavy metal screens to prevent the ingestion of bedding* roughage* They were not allowed access to Due to the absence of bedding the pens were heated with over­ head heat lamps* VHhole milk feeding with open pails at the rate of 4 lb* -tarice daily was initiated as soon as the calves would drink* On the sixth day of age the calves were placed on the experimental rations for the first period* The first fecal and urine collection period for each calf commenced on the tenth day of age* The composition of the various rations fed is presented in Table 9*. It should be noted that during periods when a re placer was fed* 2 lb* of evaporated milk was replaced by 0*5 lb* of replaoer* The calves were fed at the same time each morning and evening throughout the experi­ ment* In experiment 3, calf C-923 was fed less than the usual amount during the first period to insure complete consumption of the ration* In the same experiment the amount of feed fed calf C-923 was increased during the fourth period due to the poor condition of the calf* with diarrhea were removed from the experiment* Calves 53- Table 7 Experimental Design of Experiment 1 Shoving the Age of Calves and Rations Fed Calf Period Age in Days C-9oo cJ-9Q2 C-&66 1 10-12 Evap* Repl* 5 Repl* 6 Repl* 4 2 17-19 Repl* 5 Repl* 4 Evap* Repl. 6 3 24-26 Repl* 6 Evap* Repl* 4 Repl* 5 4 31-33 Repl* 4 Repl* 6 Repl* 5 Evap* ♦Repl*— milk replaoer* Table 8 Experimental Design of Experiment 3 Shoving the Age of Calves and Rations Fed Calf Period Age in days fl—922 C-923 C-926 6-826 1 10-14 W*M. Repl? 7 Evap* Repl* 8 2 18-22 Repl. 7 Repl* 8 W*M* Evap* 3 26-30 Evap* W*M* Repl* 8 Repl* 7 Repl* 8 Evap* Repl* 7 W*M* 34-38 4 ♦kepi•--milk replacer• Table 9 Composition of Daily Rations Ration Whole Milk lb. Ingredient Evaporated Milk lb* Water lb* Milk Replacer lb* — Whole milk 8 — Evaporated milk — 4 4 — Milk replacer — 2 6 0*6 54- Table 10 Composition of Milk Replaoers Used in Experiments 1 and 3 Ingredients 4 6 Milk Replacer 6 7 8 Ground corn 57.2 53.2 44.2 57.4 53.4 Soybean flour (52.4?£) 40.0 34.0 38.0 40.0 34.0 Distillers dried solubles — 10.0 Boiled oats — — 10.0 — — 15.0 Steamed bonemeal 1.5 1.5 1.5 1.5 1.5 Calcium carbonate 0.5 0.5 0.5 0.5 0.5 Salt 0.5 0.5 0.5 0.5 0.5 5* 0.2 0.2 0.2 Vitamin and trace mineral** 0.1 0.1 0.1 0.1 0.1 100.0 100.0 100.0 100.0 100.0 Baciferm — Total mm mm * Contained 5 gm* bacitracin per lb* ♦♦Mixture contained: Vitamin A concentrate 20,000 U.S.P. units/guu 20 gm* Irradiated yeast, 9,000 I.U. Vitamin D/gm* 5 gm* Cobaltous sulfate (CoSQ^^HgQ) 3 gm* Cupric sulfate (CuSO^’SHgO) 2 gm* Ferrous sulfate (FeS04*7H20) 11 gnu -55- Table 3 1 Chemical Analyses of Feeds Used in Experiments 1 and 3 Feed DM W Ash % OF EE % % CP % NFB Ca P % % Replacer 4 89*45 5.20 2*09 4*28 25*50 52.37 .743 .674 Replacer 5 88*54 5.35 2.21 4*30 24*28 52.19 •706 .667 Replacer 6 89*67 5.41 1.97 4.77 26.20 51.32 .747 .693 Replacer 7 87*81 5*21 2.00 4*28 24.31 52 .02 •721 .651 Replacer 8 87.01 5*69 2.04 4.92 23.75 50.61 *882 .746 Whole milk, Period 1 11.84 •67 -- 3.60 3*26 4.31 .123 •096 Whole milk. Peri©d 2 11.67 •64 — 3*40 3*25 4.38 •123 .096 Whole milk, Period 3 11.40 •64 — 3.60 3*05 4.21 .123 .096 Whole milk, Period 4 11.73 •60 mm mm 3.40 3.27 4.46 •123 .096 Evap* milk Lot 1 26*25 1.51 — 9.96 6.08 8.70 .238 .188 Evap* milk Lot 2 25.82 1.49 — 7.78 6.28 10.27 .238 •188 Evap* milk Lot 3 25*19 1.44 — 7.89 7.12 8.74 .238 .188 Formulation of Milk Replaoers The composition of the milk replaoers used in experiments 1 and 3 is presented in Table 1 0 # Milk replacers 4 and 5 are comparable to milk replacer 7 and 8, respectively, with the exceptions of the type of distillers dried solubles used and the use of antibiotic in experiment -56- 1 but not in experiment 3* The protein content was adjusted by vary­ ing the amounts of ground corn and soybean flour. To facilitate the use of milk replacers as gruels, the corn, dis­ tillers dried solubles and rolled oats were finely ground. The trace ingredients were premixed before being added to the final mixture. The mixed feeds were stored in metal containers to prevent contamination. The chemical analyses of the Collection of feeds used are presented in Table 11* Feces and Urine Feces were collected using 8 x 3 product of Safeway Products Division, York) (Eknery, 1951). shown in Fig. II. x 15 inch pliofilm bags (SafeIon, Yorkville Paper Co., Inc., New The bags were prepared with cellulose tape as The long strips of cellulose tape were placed on first then crossed by smaller pieces to prevent tearing when the long tapes were cut to form the flap. tapes. Care was taken not to out the cross After the bag was taped and cut as indicated in Fig. I and II the tail opening was made by cutting a square hole, the approximate size of the tail, and reinforcing with cellulose tape (Fig. III). The calves were prepared by clipping the entire area back of the hip bones and flank down to the hook. were also clipped. The undersides of the calves A web strap ij- inches wide and approximately 9 inches long was attached to the undersides of the calves (Fig. IV) with branding cement (product of Nebraska Salesbook Co., Lincoln, Nebraska) (Hobbs 1950). Another strap was attached to the backs of the calves with branding cement as shown in Fig. V. et al., -57- The bag was attached by passing the tail through the tail opening and passing the bag under the baok strap, folding over the strap and taping down with strips of oellulose tape (Fig. VI). The lower flap (Fig. VII) was attached by passing the flap between the lower strap and the body, folding baok and winding with oellulose to fit the bag snugly without undue strain. tape.Care was taken The bag was removed by cutting with scissors. After being removed, the bag was weighed with its contents, cut open and the contents placed in a glass jar. The glass jars containing the feces were kept in a refrigerator and the contents dried immediately after collection of the last sample. The bags were checked 4 times a day. During periods of replacer feeding it was often necessary to change the bags 4 times daily. How­ ever, during milk feeding periods once a day was usually sufficient. During the collection periods the calves were kept in metal cages 36 in. wide, 30 in. high and 48 in. deep (product of Geo. H. Wahmann Mfg. Co., Baltimore, Md.)» The calves stood on a heavy ooarse-mesh screen with a finer screen and a urine funnel and drain below. The two screens and funnel were removable. The urine was collected in a glass carboy containing 20 ml. of concentrated hydrochloric acid. At the end of the collection period the urine was measured and samples saved for ohemioal analysis. urine samples were refrigerated until analyzed. The Fig. II Preparation of bag before cutting flap Fig. Ill Finished bag - 56 - - c u r C£LlUlOS£ T/7P£ T /7 /l 0 /°£ A ///V G -C £ l l U lO S P T / 7 P £ FlFP Fig. IV Position of lower strap Fig. V Position of top strap - 59 - '& £ /? of /? r r / / c H M £ / \/ r ■ST/tFF ■SCFO TO M S T F F P -F F F F O F F T T F C F M F A /T Fig* VI Attachment of pliofilm bag to top strap Fig* VII Attachment of pliofilm bag to lower strap - 60 - -/?/?£# of /?rr/7c//M£/vr C P IL U IO S P T / 7 f £ C P U UL O S P T P P £ ---P / t £ P OP p r r p c p M £ A / r -61- Analytical Procedures Milk replaoers: Dry matter, crude fiber, nitrogen, ether extract, ash, calcium and phosphorus (A*0*A*C*, I960)* Milk: Nitrogen (Kjeldahl), fat (Babcock), total solids (Mojonnier), wet ash for calcium and phosphorus (Brenner and Harris, 1939) using selenium oxychlorlde as a catalyst, calcium (modification of Shohl and Fedley, 1922) and phosphorus (modification of Fiske and Subbarow, 1923)* Feces: Dry matter, crude fiber, nitrogen, ether extract, ash, calcium and phosphorus (A*0*A*C*# 1950), Urines Nitrogen (Kjeldahl), wet ash for calcium and phosphorus (Brenner and Harris, 1939) using selenium oxychloride as a catalyst, calcium (modification of Shohl and Pedley, 1922) and phosphorus (modi­ fication of Fiske and Subbarow, 1925)* Statistical analyses: Calculation: (Snedeoor, 1946)* The coefficients of apparent digestibility of the milk replacers were determined by difference* Nitrogen, oalcium and phosphorus balances were calculated on the milk replacer ration as fed which included the evaporated milk* RESULTS Experiment 1 The coefficients of apparent digestibility obtained in this experi­ ment, using 6-day preliminary periods and 2-day collection period, are presented in Table 12• The average apparent digestibilities for evapo­ rated milk were: dry matter, 89.6; crude protein, 79.1; ether extract, 91*4; and nitrogen-free extract, 97.0%. The average coefficients of apparent digestion for the milk replaoers were: dry matter, 51.4; crude protein, 20.4; crude fiber, - 1 2 .lj and nitrogen-free extract, 70.8. The apparent digestibility of the ether extract for the milk replacers was not calculated since the digestibility of the replacers was determined by difference and the ether extract content of milk was considerably greater than that in the milk replacers. Digestibility data for indi­ vidual animals for each period are presented in Appendix Table 2. Analyses of variance of these results (Table 13) indicated signif­ icant differences among the various feeds in the apparent digestibility of the dry matter and nitrogen-free extract portions. The differences due to animals and periods were not statistically significant. The coefficients of apparent digestion of the dry matter are pre­ sented by periods in Fig. VIII and Appendix Table 2. The dry matter of the evaporated milk was 81% digested by a 10- to 12-day-old calf and an average of 93.3% by 17- to 34-day-old calves. In contrast, the mean dry mat ter digestibility of the milk replacers increased from 32.9/fe for 10- to 12-day-old calves to 64.9% for the 24- to 34-day-old calves. 63' The orude protein of the evaporated milk was 60.1% digested by the 10- to 12-day-old calf and an average of 85.6% by 17- to 34-day-old calves (Fig. XX and Appendix Table 21 • The digestibility values for the crude protein of the milk replacers were much lower and more variable. The nitrogen-free extract (Fig. X) was the most digestible nutrient in both the evaporated milk and in the milk replacers. In the evaporated milk it was equally as digestible the first period as in later periods. However, the nitrogen-free extract of the milk replacers was less di­ gestible during the first period and reached a maximum in the third period. An average positive nitrogen balance of 3.69 gnu daily was obtained on the evaporated milk compared to the negative values with the milk replaoer rations (Table 12). Nitrogen retention on the evaporated milk was lower in the first period than in succeeding periods (Appendix Table 3). For the milk replacers the nitrogen balance tended to be negative for the first two periods and positive during the other two periods. Studies on the calcium metabolism (Appendix Table 4) of the calves indicate that they were in positive balance at all times. Calves fed the evaporated milk retained an average of 59.7% of their calcium in­ take while calves fed the milk replacer rations retained a n average of 31.4% of their calcium intake. Calcium retention varied among periods. The data on phosphorus metabolism show that calves fed evaporated milk retained an average of 54.5% of their phosphorus intake compared to an average of 31.1% for calves receiving the milk replaoer rations. The retention of phosphorus was low during the first two periods in calves receiving the milk replacer ration (Appendix Table 5). -64- & CO CD • rH ID O • rH rH O • rH ID OS • O >0 O] CD CM Q CM • rH 00 rH • rH CM CM • rH CM 0» • O O) to Ok lD • 8 9 rH Cl PQ CD • «a s s CO 0* ID to e- • to • CO • ID to 0 1 o• o CM fco> t- CM 0> CO b- 1 1 o• o rH CM • tHI -1 • Oi o o> CM • bCM o fc- • 0« CM iD • Oi CO CO • CO ID CO • rH to * PQ i-l *1! 1 * U » -P a ® i 0 « -.0 fc O 4h »4 • rH CO •H I cm ■3 +> 3 9 •r» -P ,0 03 •H ■P CO -HI * •rI rQ *rl -P rH « €L b0| *H Q o> • © bO Jfl ■H 6-1 as>s« 1 rH • Ok 1 rH • u a Ok o> * CO 0» CO CO • t- 9 a •H 8 •D •p 0 •n o £ U o Pi 0 > W 0* h © O 0 i—1 Pi 0 P0 ID CO U ft* © © O 0 rH rH £ « Pi O •0 S 8 h 5£ © o 0 0 •c? P* 9 4> CO ■P O a 65- Table 13 Analyses of Variance— Experiment 1 F values Source ^ m CP NFS N Ca P Periods 3 2*94 1*16 2*43 3*20 .26 1.18 Animals 3 •37 •95 1.47 1.26 .88 1.38 Treatments 3 6.47* 6.00* 1.87 2.78 3.43 Error 6 2*80 * Heed 4*76 for P - *05 Table 14 Dry Matter Digestibility of Whole Milk and Evaporated Milk— Experiment 2 Age of calves Days Whole milk Evaporated milk % % 8-10 96.5 — 81.6 10-14 14-18 92.0 90.4 18-22 95.9 93.4 22-26 96.3 93.4 26-30 --** 30-32 * no samples due bo diarrhea **taken off experiment due to diarrhea 90.3 92.3 *• rH 00 rH CO CM O O 3 to H» S to to • c- o 03 3 3) •3 © O o 66' • • b- at H* • o • O to to • o CO CO • iH to -• O 9 © 03 a © O CM • to at o 03 • CM 1 • © 1 S rH as to w +> >» a •H otf a Vi at rH CM a Hi rH • t* os o> • to * os t- 1 • 1 1 H* • Hi CM • 1 1 rH o • H* I 1 03 • 00 c- 13 IT «> rH X -§ nt U CH o Vi (*• o *H 8k o EH -d v. aS 4> -cS A 9 • r l -P H CO £ U to *hi © © h0J2 •rl EH °© TJa to 1 •H iJCI 00 •H • fc- 4» © ®*i rH o> • CO GO rH OS O to • OS to CM *r# Q & ■ OS • b» to • t>- CM rH • 113 Hi • O rH c© © © v« © CD • Hi OS • to CO rH • Os IQ rH ■ • U3 U3 to to • to «H O 3 Vi O Vi d € •d • rH O &« Vi © V* 14 d I 3 3 •©d 9 5 © rH P« I 3 © rH PS © PA Vi -P CO -67- Bxperiment 2 A comparison of the apparent dry matter digestibilities of raw whole milk and evaporated milk by two calves is presented in Table 14* The coefficients of dry matter digestibility averaged 95.2 for the raw whole milk and 90.3 for the evaporated milk. The dry matter of the evaporated milk was 81.6% digestible during the 10- to 14-day age period and 90.4/^ during the 14- to 18-day age period. The dry matter of the whole milk was more digestible throughout the experiment. The missing values were due to sudden onset of diarrhea which interfered with feoes collection. Experiment 3 The mean coefficients of apparent digestibility of the feeds used in this experiment* using 4-day preliminary periods and 4-day collection periods cure presented in Table 15 and individual data in Appendix Table 6. The average coefficients of raw whole milk were: dry matter* 94.8; crude protein* 90.1; ether extract* 97.8; nitrogen-free extract* 97.1. The corresponding average coefficients for the evaporated milk were 86*7* 76.9, 88.1 and 94.9* respectively* In comparison, the average apparent digestibility of the milk replacers was as follows* dry matter, 57.1; crude protein, 21.5; ether extract, 46.5; crude fiber, 0.9; nitrogenfree extract* 77.8%. In all cases the values for the milk replacers were lower than those obtained with milks. This was particularly true of the crude protein portion of the feed. When an analysis of variance was made it was found that the variance in apparent digestibility among feeds was significant for the dry matter -68- and nitrogen-free extract and highly significant for the crude protein (Table 16). The variance among animals was not significant* Crude protein digestibility also varied significantly among periods* The coefficients of apparent digestion of the dry matter in the various feeds are shown by* periods in Fig* XI* The curves show that the apparent digestibility of the dry matter of raw whole milk was high* averaging 94*8%* with little variation due to period* That of the evap­ orated milk was lower during the first period but reached its maximum value by the second period* The dry matter digestibility of the milk replacers was low during the first period* increased during the second period and reached its maximum in the third period (26 to 30 days of age)* The average coefficients for the dry matter of the milk replacers were 25*0* 52*6* 77*2 and 72*7* respectively* for the four consecutive periods* The apparent digestibilities of crude protein by periods are pre­ sented in Fig* XII and Appendix Table 6 * The orude protein of the raw whole milk was 81*2* 92*8* 93*2* and 93*0% digested in the four con­ secutive periods* The corresponding values for the evaporated milk were 56*5* 80*7* 82*7* and 87*8%* The me an coefficients of digestibility for the crude protein of the milk replacers were -26*5* 8*7, 55*6 and 48.2, respectively* for the four consecutive periods. In all four feeds the nitrogen-free extract was the most digestible nutrient (Fig. XIII) as was found in Experiment 1* The apparent digest­ ibility of the nitrogen-free extract of the raw whole milk and evap­ orated milk were 97.1 and 94.9%, respectively, with little variation due to period. In contrast, the nitrogen-free extract of the milk re­ placers for the four consecutive experimental periods averaged 57.9, 80.4, 85.9 and 87.2%, respectively. -69- The coefficients of digestibility for the dry matter, crude protein and nitrogen-free extract for the four feeds were averaged for the third and fourth period. The results are shown in Fig. XIV* The data show that there is very little difference between the two milk replacers in the apparent digestibility of the dry matter, crude protein and nitrogenfree extract. The evaporated milk was less digestible than the raw whole milk but the differences were smaller than when all four periods were considered. The largest difference occurred between the milks and milk replacers in apparent crude protein digestibility. Analysis of variance of the nitrogen balance data indicated sig­ nificant differences among feeds (Table 16). The daily nitrogen balance on raw whole milk averaged+7.36 gm., evaporated milk,+ 3.20 gm., and the two milk replacers averaged -1.18 gm. Nitrogen retention also varied significantly with periods, as occurred with crude protein digestion. Negative nitrogen balance was obtained with evaporated milk during the first period and with milk replacers during the first two periods (Appendix Table 7). Calcium retention was significantly greater for calves fed raw whole milk than for those fed the evaporated milk or milk replacer rations (Appendix Table 8 ). The calves fed raw whole milk retained 3.6 gm. or 81.6% of their calcium intake compared to an average of 1.6 gm. or 39% by calves fed either evaporated milk or milk replacer rations. Marked variations in calcium retention were observed among periods. The phosphorus balance was also significantly affected by ration (Appendix Table 9). Calves fed raw whole milk retained 60.9% of the phosphorus intake compared to- 25.5% retained by calves receiving evap- 70- orated milk and 19*2^ and 14*2% by the calves receiving milk replacers* The retention of phosphorus by calves receiving evaporated milk was negative during the first period* Low or negative phosphorus balances were observed during the first two periods when milk replacers were fed* Table 16 Analyses of Variance--Experiment 3 F Values Source df Ell CP 5*06* 2*14 5*03* *61 1.37 6*26* Periods 3 4*29 Animals 3 *83 Treatments 3 Error 6 8*94* 12.14** a Need 4*76 for P s •05 ★♦Need 9*78 for P r .01 NFS Ca P *28 •90 •28 1*21 •48 7.44* 9.28* 5.12* N - 71 - lOOr 8 0 Apparent digestibility (%) /s \ 6 0 L E G E N D 4 0 Evaporated X / ♦ 20 V ♦ / Replacer 4 Replacer 5 Replacer 6 0 2 Collection Fig* VIII* 3 period Apparent dry matter digestibilities by periods^-Experiment 1 milk Apparent digestibility (%) 60 4 0 20 0 -20 - 4 0 - 6 0 L E G E N D Evaporated / — 0 — / 7 Replacer 4 Replacer 5 Replacer 6 - 8 0 -100 2 Collection p'ie, IX* 3 period A p p a r e n t crude protein digestibilities by per?.odt-~-'J?:perii!!ent 1 milk (%) digestibility L E G E N D Apparent Evaporated 0 Replacer 4 Replacer 5 Replacer 6 2 Collection period Fig, X* App ar en t n5 trogen-free e x t r act digestibilities by p e r i o d s — E-xperiment 1 milk 100 Apparent digestibility ( % ) 8 0 6 0 r L E G E N D 4 0 Whole milk Evaporated Replacer 7 Replacer 8 20 0 2 Collection Fig* XI* 3 period Apparent dry matter digestibilities by periods--Axperiment 3 milk - 75 - Apparent digestibility (%) 100 L E G E N D -40;' = Whole milk — Evaporated — Replacer 7 — Replacer 8 -80 Collection Xig* XII* period Apparent crude protein digestibilities by periods-— Experiment 3 milk cr* S CO a> co di L E G E N D Apparent ; Whole ■ 4 0 milk Evaporated Replacer 7 Replacer 8 milk 20 0 2 Collection 3 period 'iga jLLli# Avparent nitrogen-free extract digestibilities by periods — 'Lxperiwert 3 -77- 100 90 LEGEND Apparent digestibility (% ) 80 Whole milk 70 Evaporated milk 60 Replacer 7 50 Replacer 8 40 30 20 Dry matter Crude protein N-free extract Fig* XIV* Apparent digestibilities of dry matter, crude protein and nitrogen-free extract of raw whole milk, evaporated milk and milk replacers by 26- to 68-day-old calves— Experiment 1 DISCUSSION A search of the literature had disclosed a paucity of data on the relation of age to digestion in the calf« Besides determining the apparent digestibility of the feed, experiments 1 and 3 were also designed to give a measure of the relationship of age to the digestibility of the feeds* In experiment 1, 2-day fecal collections were made beginning at 10, 17, 24 and 31 days of age* In experiment 3, using 4-day collection periods, the corresponding ages were 10, 18, 26 and 34 days* The technique devised for the collection of feces from young calves satisfied the requirements of this investigation* This method embraced freedom of movement by the calves, low cost, and ease of attaching and removing the bags* One difficulty observed with this method of feoal collection was possible leakage of laxative feces from the bag when the oalf was lying down* In general very little difficulty was encountered when the feces were costive and the bags were changed 4 times daily* The apparent digestibilities of three milk replaoers and evaporated milk were studied in experiment 1* Evaporated milk was used both as the control and to supply the milk portion of the replacer rations* The data in Table 12 indicate significant differences between the coeffi­ cients of digestion for evaporated milk and the milk replacers* How­ ever, the coefficients of digestion for the evaporated milk were lower than those reported for whole milk by Blaxter and Wood (1952a) in calves and Wellman (1914) in pigs* Parrish et al. (1953) using 1- to 17-day-old calves also observed higher values for whole milk with the exception of 79- the crude protein ■which was equal to the crude protein in the present investigation* The milk replacers used in this study were significantly less digestible than the evaporated milk (Table 12) and subject to marked variations among periods* The variations were believed to be due to die shortness of the collection period* The evidence suggested that 2-day collection periods were insufficient for valid results when milk replacers were fed* A marked decrease in the variations occurred after 4-day collection periods were adopted* A 2-day collection period seemed to be adequate when evaporated milk was fed# Experiment 2 was conducted to compare the apparent dry matter digestibility of evaporated and raw whole milk in a continuous trial with two calves* It was found throughout the experiment that the appar­ ent dry matter digestibility of the evaporated milk was lower than that of raw whole milk (Table 14)* The average coefficient of dry matter digestion of raw whole milk was 95*2 which is in agreement with the results reported by Wellman (1914), Hughes and Cave (1931), Blaxter and Wood (1952a) and Parrish £ t al* (1953)* In comparison, the dry matter of the evaporated milk was 81*6^ digested by a 10- to 14-day-old calf in the first experiment* In the following collection period (14 to 18 days of age) the apparent dry matter digestibility of the evaporated milk had increased to 90*4% which is comparable to that of the evaporated milk in the first experiment. These results indicate that the dry matter of the evaporated milk is less digestible in the young calf than is that of raw whole milk* A comparison of raw whole milk, evaporated milk and two milk re­ placers was made in experiment 3, using 4-day collection periods, in an -80- attempt to decrease the variations observed in experiment 1* The average coefficients of apparent digestibility of the dry matter, ether extract and nitrogen-free extract of raw whole milk were 94.8 , 97.8 and 97.1, respectively (Table 15). Similar values were reported by Wellman (1914) with pigs, Hughes and Gave (1931) with 7^- to 8-month-old calves, Parrish et al. (1953) with 1- to 17-day-old calves and Blaxter and Wood (1952a) with with 5- to 14-day-old calves. The apparent digestibility of the dry matter for tie raw whole milk is also in agreement with the value obtained for the raw whole milk in experiment 2. The average apparent digestibility of 90.1% for the crude protein of raw whole milk is lower than the values cited by Wellman (1914), Hughes and Cave (1931) and Blaxter and Wood (1952a). However, as ean be seen in Fig. XII, the low average value is due to the low apparent digestibility of the crude protein during the first period. In the following periods the values were equal to those reported by the investigators mentioned above. Parrish et al. (1953) also observed low crude protein digestibilities for colostrum and whole milk in calves between the ages of 3 and 8 days. They reported apparent crude protein digestibilities of 83% at 3 to 4 days of age and 86% at 5 to 8 days of age# In 14- to 17-day-old calves it had increased to 93% which is in agreement with the results in experiment 3# A comparison of evaporated and raw whole milk data for experiment 3 (Table 15) indicates that evaporated milk is less digestible than raw whole milk under the conditions of this experiment. The apparent digest­ ibility of the crude protein portion of the evaporated milk was noticeably lower than that in rsw whole milk and also slightly lower than that in -81- the evaporated milk in experiment 1 . In their experiments with rats, Nevens and Shaw (1932) also observed a lower crude protein digestibility in evaporated milk than in whole milk. However, Henry and Kon (1938) and Fairbanks and Mitchell (1935), using rats9 were unable to demonstrate a difference between the crude protein digestibilities of evaporated and whole milk. A later experiment by Kraft and Morgan (1951) suggested a possible difference between animals in their ability to utilize the protein of heated milk. These authors reported that heating of skimnLilk had no effect on nitrogen retention in dogs but a marked decrease occurred when fed to weanling rats. The lower values for the evaporated milk as compared to raw whole milk in the present investigation suggest that young calves, at the ages used, may not be physiologically equivalent to the animals used by most investigators. The evaporated milk values were consistently lower, although the differences were small. This suggestion is not in agreement with Schroeder et al. (1953) who claim that differences attributed to species of experimental animals used are in reality due to the intensity and duration of heat used in processing the milk. However, it should be noted that in the present investigation 3 different lots of evaporated milk were used. The results for all 3 lots were consistently lower than those for raw whole milk. Inspection of the coefficients of digestibility in experiment 3 (Table 15) reveals that the milk replacer values are lower than are those for the milks. Again as in experiment 1 the crude protein in the milk replacers was considerably less digestible than the crude protein in the milks. Less difference occurred in the nitrogen-free extract portion. The crude fiber of the milk replacers in experiment 3 appeared to be -82- indigestible, a finding which agrees with the results in experiment 1* This suggests that crude fiber has little or no value in the nutrition of the young calf before the rumen begins to develop unless its presence stimulates rumen development. McCandlish (1923) had previously suggested that bulk in the diet stimulated the development of the alimentary tract in the young calf. The ether extract values for the milk replacers were of little value because the ether extract portion of the milk replacers was small in comparison to that in the milk fed with them. Since the milk replacer digestibilities were determined by difference, any error in the milk value would be magnified out of proportion in the ether extract digest­ ibility for the milk replacers. The digestibilities of the various feeds as they might be affected by age of the calf were studied in experiments 1 and 3. When the coef­ ficients of apparent digestibility of the dry matter, crude protein and nitrogen-free extract for experiment 1 were plotted graphically by periods (Fig. VIII, IX and X), it was noted that the digestibility coefficients varied with age of the calf. The values obtained in experiment 3 (Fig. XI, XII and XIII) were similar to those in experiment 1, but the results with milk replacers were less variable among periods. to be due to the longer collection period. This was believed The results in experiment 3 demonstrate that the digestibility of raw whole milk varies little with age of the calf. In contrast, evaporated milk is not as digestible by the 10- to 14-day-old calf as by the 18- to 22-day-old calf, a difference essentially attributable to the lowered digestibility of the crude protein in the evaporated milk. -83- The digestibility patterns also indicate that the calves were it to utilize the milk replacers satisfactorily until the third period, when they were approximately 25 days of age (average for experiments 1 and 3). These results substantiate the conclusion in Part 1 that the end of the critical period in the life of the young calf is approximately 25 days of age. This was indicated by the increased feed consumption, increased weight gain and improved general appearance of the calves. The age cited is also in agreement with Shaw et al. (1918) who reported that 4to 7-day-old calves were able to digest only one-fifth of the starch con­ sumed but at 21 to 28 days of age they were able to digest well over 90 percent of the starch in the ration. It was suggested in Part I that the increased ability of the calves to utilize the milk replacers at approximately 25 days of age may be due to the development of rumen function. However, the data on crude fiber digestion (Tables 12 and 15) suggest that the increased ability of the calf to utilize milk replacers may not be due to increased rumen function* As the rumen develops the apparent digestibility of the crude fiber would be expected to increase as occurred with the other components of the milk replacers. However, in experiments 1 and 3 the apparent crude fiber digestibility was essen­ tially zero during the third and fourth periods. It is suggested that the improved utilization of milk replacers by calves at approximately 25 days of age may be due to same unidentified physiological change. An inspection of the data in Fig. XIV indicates that in 26— to 38day-old calves the apparent digestibilities of raw whole and evaporated milk are similar for dry matter, crude protein and nitrogen-free extract. The apparent digestibilities of the two milk replacers were almost iden- -84- tical, and they were significantly less digestible than the milks. The apparent digestibilities of the milk replacers were compared with those obtained on calf meals with 9-month-old calves by Archibald (1928;, The coefficients for the crude protein of the milk replacers were considerably lower, dry matter slightly higher and the nitrogen-free extract noticeably higher than those of the calf meals* On the basis of this comparison it appears that crude protein is less digestible by 26- to 38-day-old calves than by 9-month-old calves* The dissimilarities cited could be in part due to differences in the composition of the rations fed* A limiting factor in the nutrition of the young calf until approx­ imately 25 days of age appears to be the lower apparent crude protein digestibility in the milk replacers* In experiments 1 and 3 (Appendix Tables 3 and 7) the average daily urinary nitrogen excretion was similar for all rations* However, fecal nitrogen varied from 1*8 gm, in the raw whole milk ration and 3*8 gm, in the evaporated milk ration to 10*5 gm* in the milk re placer rations* Since the dry matter intake on all diets was essentially the same the metabolic fecal nitrogen excretion should be fairly constant among the rations* Some increase in metabolic fecal nitrogen may occur due to the physical state of the milk replacers as compared to that of the milks* It is postulated that the increased fecal nitrogen observed in calves receiving the milk replacer rations primarily represented undigested protein which could not be assimilated by the calf* The failure of digestion might be attributable to a lack of sufficient enzymes for splitting the protein molecules* The decreased apparent crude protein digestibility and the increased fecal nitrogen excreted by calves on evaporated as compared to raw whole -85- milk may be due to the effect of heat on the milk protein during pro­ cessing* This has been indicated by Pader et al. (1948) who reported that heating of casein deoreased lysine liberation* The decreased lib­ eration of lysine might be attributed to the formation of a. linkage which was enzyme resistant* Fairbanks and Mitchell (1935) also indicated that the use of increasing amounts of heat decreased the digestibility of the milk protein* Calcium retention was variable both between experiments and periods* It was observed that calcium retention varied little with age* However, calcium retention by calves fed raw whole milk was greater than by calves fed evaporated milk or milk re placer rations* This suggests that the calcium of raw whole milk is more efficiently utilized by the young calf than that of the evaporated milk or milk replacer ration# Urine analyses indicate a low urinary calcium excretion by the calf (Appendix Tables 4 and 8)* In experiment 1 the urinary calcium excretion amounted to 2*8^ of the total calcium excreted* 1*9% of the total calcium excreted* In experiment 3 it was These values are similar to the 2% urinary calcium reported by Blackwood et jal* (1936) and lower than the 5% found by Blaxter and Wood (1952a)* Analyses of data on phosphorus balances (Appendix Tables 6 and 9) also showed marked variations* Marked variations in calcium and phos­ phorus balances were also noted by Blackwood et al. (1936)* It was ob­ served that phosphorus retention was lower the first two periods than during the last two periods. Phosphorus retention tended to vary to some degree with nitrogen retention* The data presented in this investigation indicate that raw whole milk is readily digested and utilized by the young calf* Apparently the young oalf is not able to digest and assimilate evaporated milk as readily as raw whole milk* although the differenoes are small* The data also show that milk replacers of the type used in this investigation are of little value to the calf until approximately 25 days of age* Thereafter these feeds were considerably more digestible* although not as digestible as comparable feeds by adult animals* SUMMARY Ton male calves were allotted to three experiments* Two groups of four 10-day-old calves each were assigned to 4 x 4 Latin square metab­ olism experiments* bag technique* Fecal collections were made utilising a simplified The apparent digestibilities of the dry matter and other feed constituents of five milk replacers* evaporated milk and raw whole milk were determined* determined* Nitrogen, calcium and phosphorus balances were The effect of age of the calves on the apparent digesti­ bility of the various feeds was studied* One experiment was conducted with two calves to compare the digestibility of evaporated and raw whole milk in a continuous trial* The variability of the milk replacer data in the first experiment indicated the inadequacy of 2-day fecal and urine collection periods* The 4-day collection periods used in the third experiment appeared to be sufficient* The mean coefficient of apparent dry matter digestion of raw whole milk was 94*8; crude protein, 90*1; ether extract* 97*8; and nitrogen-free extract* 97.1* The dry matter of evaporated milk was 76*8# digested by a 10- to 14-day-old calf and an average of 90*0$ by 19- to 38-day-old calves* The average apparent dry matter digestibility of the milk replacers increased from 25*0$ for 10- to 14-day-old calves to an aver­ age of 75*4$ for 26- to 38-day-old calves* Similar increases in digest­ ibility with increased age of the calves were noted for the crude pro- - 88 - tain and nitrogen-free extract fractions* The most digestible fraction was the nitrogen-free extract and the least digestible the crude protein. The crude protein of the raw whole milk was slightly less digestible by the 10- to 14-day-old calf than in subsequent periods. £’or the evap­ orated milk it was low for the 10- to 14-day-old calf and at its maximum value by 19 to 22 days of age* During the first collection period the crude protein of the milk replacers was considerably less digestible than that of the milks. It attained its maximum value by 26 days of age. Between the ages of 26 and 58 days the evaporated milk was slightly less digestible than the raw whole milk. The different milk replacers were approximately equally digestible but were significantly less so than the milks. This was most noticeable in the crude protein fraction. Crude fiber was essentially indigestible throughout the experiments. The percentage and actual amount of nitrogen, calcium and phosphorus retained was greater for calves fed raw whole milk than those fed the evaporated milk or milk replacer rations. 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APPENDIX 107- CO CM M* to Oi CM tO CO CO CM O O rl • • • • • • • CM CM CM r-4 CM CM CM CM 00 tO M* CJ> O i—< O H M 1} © N © s w m © oi s o © © to to © s © CM CM CM CM CM CM «-f CM CM CO CM CM * • • • • • • u © M o -i © rl H a o< © ^4 ■H pH O -H A • £3 *3 • CS £ >* O O O to O O O CM CM CM 'M* tf> O d> © <0 © © © U} Cft C- CO o o> oo 00 ^ © (O N © © • • • • • • • O O 388 CO O O s o © © (O (O © © to s O Q OO O O O © © s © oo © 5 o sO © © © CM r—I CM 'M* 0» CM H O O « W r t « CO -M* CM CO lO O lO U> vO tO O O © © © O © C7> © © M S © IO 4* © © © s © © © O © -P Xi H • a •H 43 OS i" t to ■# 44 a © c * &4 iqo o O o *3 Q K •H •n lo iq CM CM CM o O O o • • • • • * • O CM CM S- CO t> to H rM ’M* CO to o> co C5 CM CM o c *. fc— to tO to to CO S csj H S © O -M* CO tO tO tO LO £O J« © • a £ CH * [*l W CO ffi o o> CO s CM CM CO CO tO LO -M1 co o> O © M* +> £ M > O H (ON O © OO O) O O © ft! W © W H W {O S © ^ H ^ CM CM CO (J> f- CM tO tO SO CO tO to tO 0O © O © © S © © H © O Q£> O 00 O © (A N © CM © ® © © © H H © © ^ O H CO CO ** W W CO <£> CO CO CO CO CO ci o • I I I I o CO N ^ fc*» t** © oo I I S I o CO Vi © M O H © •H r—< a P* 5 CM co © S © S S S © S I I H © ffl © 108- Appendix Table 2 Coefficients of Apparent Digestibility of Feeds by Individual Animals for each Period— —Experiment 1 Period 1 2 3 4 Feed Evap. Evap. Evap. Evap* Animal C-899 C-902 C-900 C-906 Average 4 4 4 4 1 2 3 4 C-906 C-900 C-90& C-899 Average 5 5 5 5 1 2 3 4 C-900 C-899 C-906 C-902 Average 6 6 6 6 1 2 3 4 Average C-902 C-906 C-899 C-900 Digestibility Coefficients CP EE CF n Pe 81*0 93*2 88*8 95*0 60,1 84.7 79.6 92.2 77.1 98.6 96.2 97.6 89.6 79.1 91.4 26.8 47.5 59.5 72.7 27.9 3.6 21.6 55.9 — -— — -42.6 8.1 -8.6 6.6 37.5 75.9 79.0 84.3 56.6 24.9 -- -10.0 72.0 58.0 65.0 77.9 61.5 39.1 -13.3 64.6 9.1 — — -0.6 -11.8 -5.8 -21.9 58.3 71.8 84.3 73.9 51.6 27.2 — -9.1 69.2 13.9 42.6 65.0 63*0 - 6809 20.5 39.8 44.8 — — -14.7 -47.8 -12.2 2.9 70.1 58.1 82o8 74*2 46.1 9.0 •• -17*2 71.3 — — — _ - — 99.1 97.7 94.3 97.1 97.0 109- Appendix Table 3 Daily Nitrogen Balances--Experiinent 1 Period 1 2 3 4 Ration Evap. Evap. Evap. Evap. Animal C-899 C-902 C-900 C-906 Average 1 2 3 4 4 4 4 4 C-900 C-899 C-906 C-902 Average 1 2 3 4 5 5 5 5 C-906 C-900 C-902 C-899 Average 6 6 6 6 1 2 3 4 Average C-902 C-906 C-899 C-900 Intake Feces Output XJrine Total got. gnu gm. 17.88 17.88 17.88 17.29 7.28 2.80 3.71 1.37 10.21 9.32 8.25 13.22 17.49 12.12 11.97 14.59 0.39 5.75 5.91 2.70 17.73 3.79 10.25 14.04 3.69 18.20 18.20 18.20 18.20 10.31 10.33 9.12 4.79 16.11 7.78 8.11 8.75 26.42 18.12 17.23 13.55 -8.22 0.08 0.96 4.65 18.20 8.64 10.19 18.83 -0.63 17.76 17.76 17.46 17.46 9.01 11.38 4.91 8.70 7.93 11.30 13.79 8.20 16.94 22.69 18.70 16.90 0.81 -4.93 -1.24 0.55 17.61 8.50 10.30 18.80 -1.19 18.45 18.16 18.45 18.45 19.71 8.85 7.58 5.96 8.45 10.21 9.79 8.31 28.17 19.07 17.37 14.28 -9.71 -0.90 1.08 4.17 18.38 10.53 9.19 19.72 -1.34 Balance gnu Appendix Table 4 Daily Calcium Metabolisra--ExperiiDant 1 Period 1 2 3 4 Ration Evap. Evap. Evap. Evap. Animal C-899 C-902 C-900 C-906 Average 1 2 5 4 4 4 4 4 C-900 C-899 C-906 C-902 Average 1 2 3 4 5 5 5 5 C-906 C-900 C-902 C-899 Average 1 2 3 4 6 6 6 6 Average C-902 C-906 C-899 C-900 Intake gm. Output Urine gm. ______ Feces gm. 4.32 4.32 4.32 4.32 0.91 0.78 3.2£ 1.76 0.07 0.10 0.04 0.07 0.98 0.88 3.26 1.83 3.33 3.44 1.06 2.50 77.2 7946 24.6 57.8 4.32 1.67 0.07 1.74 2.58 69.7 3.85 3.85 3.85 3.85 3.70 2.57 2.08 2.05 0.09 0.05 0.02 0.02 3.79 2.63 2.10 2.07 0.06 1.22 1.74 1.78 1.4 31.7 45.3 46.2 3.85 2.60 0.05 2.65 1.20 31.2 3.76 3.76 3.76 3.76 2.44 2.82 2.30 2.40 0.09 0.09 0.07 0.10 2.53 2.91 2.37 2.50 1.23 0.85 1.39 1.26 32.8 22.6 37.0 33.6 3.76 2.49 0.09 2.58 1.18 31.4 3.86 3.86 3.66 3.86 2.20 3.26 2.79 2.07 0.14 0.00 0.07 0.04 2.34 3.26 2.86 2.11 1.52 0.59 0.99 1.74 39.3 15.4 25.7 45.2 3.86 2.58 0.06 2.64 1.22 31.6 Balance Retained "Total gm. gm. ...% - 111- Appendix Table 5 Daily Phosphorus Metabolism?*—Experiment 1 Ration Animal Intake Feoes Output Urine Total gm* gm* gm* 3*41 3*41 3*41 3*41 0*75 0*41 1*63 0*72 0.72 0*52 0*50 1*05 1.47 0*93 2 *04 1.78 1*94 2*48 1*37 1*63 56*9 72.7 40*2 47*9 3*41 0*85 0*70 1*55 1*86 54*5 3*20 3*20 3*20 3*20 2*08 1*59 1*04 1*05 1*06 0*64 0*75 0.41 3*14 2*23 1.79 1*46 0*06 0.97 1*41 1*74 1*9 30*3 44*1 54*1 3*20 1*44 0*71 2*15 1*05 • CM to Period 3*22 3*22 3*22 3*22 1*52 1.75 1*10 1*33 0.75 0.76 0*99 0*64 2.27 2*50 2*09 1*98 0*95 0.72 1*13 1*24 49*5 22*4 35*1 38*5 3*22 1*42 0*78 2*21 1*01 31*4 3*28 3*28 3*28 3*28 1*89 1*94 1*41 1*19 0.75 0*79 0.67 0*68 2*64 2.73 2*09 1.87 0*64 0*55 1*19 1*41 19*6 16*8 36*3 43*0 3*28 1*61 0.72 2*33 0*95 29*0 gm* 1 2 3 4 Evap* Evap* Evap* Evap* C-899 C-902 C-900 C-906 Average 1 2 3 4 4 4 4 4 C-900 C-899 C-906 C-902 1 2 3 4 5 5 5 5 C-906 C-900 C-902 C-899 Average 1 2 3 4 6 6 6 6 Average C-902 C-906 C-899 C-902 gm* Retained % oo Average Balance - 112- Appendix Table 6 Coefficients of Apparent Digestibilities of Feeds by Individual Animals for each Period--Experiment 3 Period Feed Animal m 1 2 3 4 W*M* W.M. W.M. W.M. C-922 C-925 C-923 C-926 Average 1 2 3 4 Evap. Evap. Evap. Evap. C-926 C-926 C-922 C-923 Average 7 7 7 7 1 2 3 4 C-923 C-922 C-926 C-925 Average 8 8 8 6 1 2 3 4 Average C-926 C-923 C-925 C-922 Digestibility Coefficients OF CP EE 92*6 96.2 95.0 95.6 81.2 92.8 93.2 93.0 96.5 97.9 98.6 98.0 94.8 90.1 76.3 91.1 87.9 91.1 NFE — 98.2 98.0 95.2 96.8 97.8 — 97.1 56.5 80.7 82.7 87.6 72.3 96.5 87.3 96.1 v -tm 97.4 95.0 94.4 92.9 86.7 76.9 88.1 33.8 50.2 76.3 76.0 -8.5 1.7 56.3 51.6 -1.0 48.9 128.6 100.2 -•2 -3.9 -8.0 -1.5 58.9 76.8 84.0 89.5 59.1 25.3 69.1 -4.4 77.3 16.3 54.8 78.1 71.2 -44.5 15.7 54.9 44.8 -110.9 -7.5 124.6 89.7 0.0 7.6 13.5 3.8 56.8 83.9 87.7 84.8 55.1 17.7 24.0 6.2 78.3 — — — 94.9 -113- Appendix Table 7 Daily Nitrogen Balances— Experiment 3 Period Ration __ _ _ _ _ _ 1 2 3 4 W.M. W.M. W.M. W.M. Animal C-922 C-925 C-923 C-926 Average 1 2 3 4 Evap. Evap. Evap. Evap. C-925 C-926 C-922 C-923 Average 7 7 7 7 1 2 3 4 C-923 C-922 C-926 C-925 Average 8 8 8 8 1 2 3 4 Average C-926 C-923 C-925 C-922 Intake Feces gm. Output tJrine gnu Balance Total gnu gnu 17*96 17.91 16.85 18.06 3.44 1.31 1.16 1.28 7.73 9.98 8.66 7.74 11.17 11.29 9.82 9.02 6.78 6.61 7.02 9.04 17.69 1.80 8.53 10.33 7.36 13.10 17.46 17.46 21.83 5.82 3.44 3.09 2.72 11.55 9.50 10.42 10.52 17.37 12.94 13.52 13.00 -4.R7 4.52 3.94 8.58 17.46 3.76 10.50 14.26 3.20 17.56 17.56 17.56 17.66 13.46 10.40 6.40 5.36 7.68 8.44 9.24 10.54 21.14 18.84 14.64 16.91 -5.58 -1.28 2.91 1.65 17.56 8.65 8.98 17.63 -0.07 17.36 17.35 17.36 18.72 16.34 8.98 5.43 6.02 8.97 14.45 10.37 9.44 25.31 23.43 15.80 15.46 -7.96 -6.08 1.55 3.25 17.70 9.19 10.80 19.99 -2.29 -114- Appendix Table 8 Daily Calcium Metabolism— Experiment 3 Period Ration Animal Intake gnu 1 2 3 4 W.M. W.M. W.M. W.M. C-922 C-925 C-923 C-926 Average 1 2 3 4 Evap. Evap. Evap. Evap. C-925 C-926 C-922 C-923 Average 1 2 3 4 7 7 7 7 C-923 C-922 C-926 C-925 Average 1 2 3 4 8 8 8 8 Average C-926 C-923 C-925 C-922 Feces gnu Output Urine total gm. gm. Balance gm* Retained * 4.46 4.46 4.46 4.46 0.43 0.58 1.43 0.60 0.02 0.01 0.09 0.11 0.45 0.59 1.52 0.71 4.01 3.87 2.95 3.75 89.9 86.8 66.1 34.1 4.46 0.76 0.06 0.82 3.64 81.6 3.24 4.32 4.32 5.40 2.24 1.34 2.92 3.73 0.01 0.06 0.02 0.00 2.25 1.40 2.94 3.73 0.99 2.92 1.38 1.67 30.6 67.6 31.9 30.9 4.32 2.56 0.02 2.58 1.74 40.3 3.80 3.80 3.80 3.80 2.59 2.55 1.43 2.36 0.05 0.01 0.03 0.02 2.64 2.56 1.46 2.38 1.16 1.24 2.34 1.42 30.5 32.6 61.6 37.5 3.80 2.23 0.03 2.26 1.54 40.5 4.16 4.16 4.16 4.50 2.75 3.19 1.90 2.53 0.10 0.02 0.04 0.06 2.85 3.21 1.94 2.59 1.31 0.95 2.22 1.91 31.5 22.8 53.4 42.4 4.25 2.59 0.05 2.64 1.61 37.9 -115- Appendix Table 9 Daily Phosphorus Metabolism— —Experiment 3 Period Ration Animal Intake Feces gm. 1 W.M. 3 4 was. was. was. z C-922 C-925 G-923 C-926 Average 1 2 3 4 Evap. Evap. Evap. Evap. C-925 C-926 C-922 C-923 Average 1 2 3 4 7 7 7 7 C-923 C-922 C-926 C-925 Average 1 2 3 4 8 8 8 8 Average C-926 C-923 C-925 C-922 Output Urine Balance Retained gm. TT- Total gm* gm* gm. 3.48 3.48 3.48 3.48 0.22 1*67 0.35 0.20 0.63 1.59 1.26 1.02 0.86 1.76 1.61 1.22 2.62 1.72 1.87 2.26 75.3 49 .5 53.7 65.0 3.48 0.23 1.13 1.36 2.12 60.9 2.56 3.41 3.41 4.26 1.12 0.75 1.06 1.69 1.72 1.06 1.54 1.22 2.84 1.81 2.60 2.91 -0.28 1.60 0.81 1.35 -10.9 47.0 23.6 31.8 3.41 1.15 1.39 2.54 0.87 25.5 3.18 3.13 3.18 3.18 1.47 1.46 0.85 1.15 1.36 1.58 1.01 1.42 2.83 3.04 1.86 2.57 0.35 0.14 1.32 0.61 11.1 4.5 41.6 19.3 3.18 1.23 1.34 2.57 0.61 19.2 3.40 3.40 3.40 3.66 1.79 1.58 0.97 1.19 1.73 1.72 1.46 1.44 3.52 3.30 2.43 2.63 -0.12 0.10 0.97 1.03 -3.6 2.7 28.5 28.3 3.46 1.38 1.59 2.97 0.49 14.2