A? “u. PERFORMANCE AND CARCASS CHARACTERISTICS IN INDIVIDUALLY FED STEER AND HEIFER CALVES BY Amos Paul Kennedy, Sr. 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.Animal Husbandry 1955 vmm-w-vk' ‘ --.., LIBRARY Michigan State University I unfineguctxp‘; 9&1 Amos P. Kennedy ABSTRACT A series of three experiments was conducted cooperatively by the Michigan Agricultural EXperiment Station and the Bureau of Animal Industry of the United States Department of Agriculture to study some of the production factors and carcass character- istics in fattening steer and heifer calves. Data were obtained on twelve steers and twelve heifers, and on the carcasses of the same animals in each of the three experiments. Cattle were . slaughtered at four different stages of finish in an attempt to match the two sexes for fatness and grade. The average initial weights for steers and for heifers were 38% and 367 pounds, respectively. Slaughter weights in Kill #, after 273 days of feeding, averaged 892 and 816 pounds. Cattle of both sexes maintained high and similar rates of gain early in the feeding period. Heifer gains decreased after the first 8% days of feeding, while steers maintained a high rate of gain for lhO days. The rate of gain for heifers decreased at a faster rate than that of steers. The difference in rate when cattle . were matched for finish.was very small and was not significant. During the first 112 days of feeding the daily total di- gestible nutrient consumption for all cattle increased rapidly and showed small differences between the sexes. After 112 days ‘the daily total digestible nutrient consumption of steers re— :mained almost level, while that of heifers decreased as feeding jprogressed beyond this point. Total digestible»nutrients required 'per pound of gain was higher for heifers than for steers fed a _ V “’3‘-" P ' Amos P . Kennedy similar time, however, when cattle were matched for finish at slaughter small differences were observed. Slaughter grades, carcasses grades and dressing percen- tages increased significantly in all cattle as feeding progressed, and each was significantly higher for heifers when cattle were compared by kills, but with similar finish the differences between the sexes were small and none were significant. - Carcass separable fat, separable fat in most wholesale cuts and ether extract content of carcass boneless meat, each in- creased as feeding progressed. The percentages of lean and bone in the carcass and in most wholesale cuts, along with the per- centages of protein and moisture in carcass boneless meat de- creased with increasing fatness, and these factors were signifi- cantly higher in steer carcasses when cattle were compared by kills. However, when cattle were matched according to finish the differences between the two sexes were small and most of the differences were not significant.“ The carcass percentages of flank, kidney knob and rib cuts increased significantly with finish in all cattle while per- centages of round and shank decreased significantly. Degree of finish had no significant effect on the percentages of loin, rump, plate and chuck in cattle carcasses. Factors that were influenced by sex were carcass percentages of hindquarter, flank and flank fat, and meat to bone ratio, ‘which were significantly higher in heifer carcasses both when cattle were compared by kills and matched by finish; and the percentages of forequarter, chuck, chuck bone, shank, shank bone Amos P. Kennedy and total carcass bone, being significantly higher in steer carcasses. _ , Wholesale cuts not significantly associated with sex as percentage of carcass when matched by finish were the loin, rib, round, rump and plate. The four measures of finish used in these experiments showed steers and heifers to be very closely matched for finish when steers were fed approximately 50 days longer than heifers. ,— ‘ ' I r .' ’ ./ I , ‘1 _ I: . . '3‘ 3‘ ‘1 -1 _ a A uni-LL}... ' " -.-"'_V'A'uiw v75’5 ,s ,__,,_,_*e u—o—u— ._. * "’,M;r__T;H--*H0"hm " --. _r_‘_ ACIQWOWLEDGEI-IEN TS The author desires to express his sincere appreciation to his Guidance Committee Chairman, Professor G. A. Branaman of the Department of Animal Husbandry, for his continuous and considerate guidance, counsel, and criticism. His authentic interest has been chiefly responsible for this accomplishment. Much is owed to Professor L. J. Bratzler of the Department of Animal Husbandry, who was always ready with his constructive criticism and suggestions which aided considerably in the development of some of the ideas put forth in this manuscript- Grateful acknowledgements are extended to Dr. W} D. Eaten of the Department of Mathematics for his generous advice upon the statistical treatment of the data; to all members of the Department of Animal Husbandry of the Michigan Agricultural Experiment Station and United States Department of Agriculture workers at Beltsville, Maryland, who collected the data. He extends gratitude to Dr. W} D. Collings of the Department of Physiology; Dr. C. A. Hoppert of the Chemistry Department; and Dr. C. R. Megee, Graduate Council representative, for their suggestions and assistance. In addition he is deeply indebted to Mrs. F. E. Golden for the excellent job of typing and arranging this manuscript; and to Mrs. B. Eichelberger, who also assisted in the preparation of some of the tables in this manuscript. To his wife, Helen, the author extends his deepest appreciation for her enduring patience and continued encourage- ment throughout this study. “r 1 ,m- - Amos Paul Kennedy, Sr. candidate for the degree of Doctor of Philosophy Final examination, July 29, 1955, 2:00 P.M. room 202 Agricultural Hall Dissertation: Performance and Carcass Characteristics of individually Fed Steer and Heifer Calves Outline of Studies: Major Subject: Animal Husbandry ‘Minor Subjects: Biochemistry and Physiology Biographical-Items: Born, September-lh, 1920, Hosston, Louisiana Undergraduate Studies, Southern University, Baton Rouge, Louisiana 19h04h7 Graduate Studies, Michigan State College, 1951-55 Experience: Staff Sgt., U. S. Army'Med. Dept. 19%3—h6 vocational Agriculture and Chemistry Instructor, l947-h8 ‘Veteran Farm Instructor l9h8-50 Chemist I in Blood Fractionation l9Sl-Date Member of Beta Kappa Chi and Sigma Xi TABLE OF CONTENTS REVIEW OF LITERATURE Effect of Length of Feeding Period on Feedlot Performance, Finish and Carcass Yields. . . . . . . Effect of Length of Feeding Period on Physical and Chemical Carcass Composition. . . . . . . . . . Effect of Sex on Feedlot Performance, Finish and carcass Yields. 0 O O O O O O O O O O O O O O 0 Effect of Sex on Physical and Chemical Composition. EXPERIMENTAL PROCEDURES Source of Calves and Feeding Methods. . . . . . . . Methods of Grading, Slaughtering, Cutting and Sampling.........o.....o...... RESULTS AND DISCUSSION . . . . . . . . . . . . . . . . . Slaughter Data. . . . . . . . . . . . . . . . . . . Carcass Data. . . . . . . . . . . . . . . . . . . . Cutting Tests . . . . . . . . . .‘. . . . . . . . . Carcass Physical Composition. . . . . . . . . . . . Physical Composition of'Wholesale Cuts. . . . . . . Carcass Chemical Composition. . . . . . . . . . . . SUMMARY'AND CONCLUSIONS. . . . . . . . . . . . . . . . . APPENDIX . . . . . . . . . . . . . . . . . . . . . . . . BIBLIOGRAPHY . . . . . . . . . . . . . . . . . . . . . . l 5 7 in 18 19 25 38 #3 1,3 56 6% 71 79 86 93 l / J I .1 / / l . - '. .' / I“ / “a .l l - h I ‘ I . » -. . ’ "\- .’ ~ .‘ s. \ _‘ -. “w" o .' ‘ \. . 0 , _ _ g | 1 l . m m; : ~~ie~ ,~.;l 4. '~ . ‘ ”Win I. ‘_ -' r: h - I. ,. . 7-;'_‘ a - A 1‘II ' 6 ,Q' .I. i * ‘ ‘ “h (I la~ a. I 7‘ at '2 . ., . . I: «.4 . a~u.., .. .:. a,- . ‘ ‘1 ‘ ' wk ’, -5. 4» . . ,. —-__‘-iw-~.~‘ It ,:___ 1.4-?“_.'='.'='.'__.-. ‘.._ .-- ' -- '—-—— LI ST OF TABLES 1. Performance of Kill I Steers and Heifers. . . . . . 21 2. Performance of Kill 2 Steers and Heifers. . . . . . 22 3. Performance of Kill 3 Steers and Heifers. . . . . . 23 %. Performance of Kill M Steers and Heifers. . . . . . 2h 5. Performance_of Steers and Heifers (By Kills). . . . 36 6. Performance of Steers and Heifers (Cattle of SimilaI. finiSh) O O O O O O O O O O O O C O C O O O 37 7. Slaughter Data (By Kills) . . . . . . . . . . . . . 8. Slaughter Data (Cattle of similar finish) . . . . . 9. Carcass Data (By Kills) . . . . . . . . . . . . . . 10. Carcass Data (Cattle of similar finish) . . . . . . arse ll. Percentage'Wholesale Cut Yield - Hindquarter. (Cold Carcass Basis). . . . . . . . . . . . . . . . ’h9 l2. Percentage'Wholesale Cut Yield of Cattle of Similar Finish - Hindquarter. (Cold Carcass BaSiS) O O O I O C O O O O O O O O O O O O O O O O O 50 13. Percentage'Wholesale Cut Yield - Forequarter. (Cold Carcass Basis). . . . . . . . . . . . . . . . 52 1h. Percentage'Wholesale Cut Yield of Cattle of Similar Finish - Forequarter. (Cold Carcass Basis) 53 IS. Carcass Physical Composition and.Meat to Bone Ratio 57 16. .Carcass Physical Composition and Meat to Bone Ratio in Cattle of Similar Finish . , , , , , , , , , , , 58 17. Physical Composition of Wholesale Cuts. (Results are expressed as percentages of cold carcass weight) 61 18. -Physical Composition of Wholesale Cuts from Cattle of Similar Finish. (Results are eXpressed as per- centages of cold carcass weight.) . . . . . .1. . . 63 19. Chemical Composition of Carcass Boneless Meat. (Results are expressed as percentage of carcass boneless meat wt.). . . . . . . . . . . . . . . . . 69 20. 21. 22. 23. 2h. Chemical Composition of Carcass Boneless Heat of Cattle of Similar Finish. (Results are expressed as percentage of carcass boneless meat wt.) . . . . Average number of days fed, weights, gains and net energy requirements of steer and heifer cattle on increasing degrees of finish. . . . , , , , , , , , Average ratios of edible meat to bone in sides firmness of lean meat and marbling of rib "eye"' of steer and heifer cattle of increasin degrees of finish. Average percentages of fat (ether extract) in edible portion of nine-ten-eleven—rib cuts are al—SOShOVmoooooooOOOOoo‘oooocooo Measures of Fatness (By Kills). . . . . . . . . . . MeaSures of Fatness (Cattle of Similar Finish). . . 7O 72 73 76 77 /, I, n‘ ‘J‘ A" I . / “a. ‘M- asegme* . : 7 I ‘— I. i; t . ,4 . fl 7 2 ‘I .I.- m... 111‘ 4‘ ' ..—-- .- LIST OF APPENDIX TABLES Measures of Fatness, Kill 1 Steers and Measures of Fatness, Kill 2 Steers and Measures of’Fatness, Kill 3 Steers and Measures of Fatness, Kill H Steers and Feed Consumed Per Hundred Pounds Gain. Feed Consumed Per Hundred Pounds Gain. Coefficients of Correlation. . . . . . Heifers Heifers Heifers Heifers. l. 2. 3. LIST OF FIGURES Average Body Weights by 28 day periods . . . . . . Average Daily Gains by 28 day periods. . . . . . . Average Daily Gain per Hundred Pounds Body weight by 28 day periods . . . . . . . . . . . . . Average Daily Total Digestible Nutrients Consumed by 28 day periOdS. O O O O O O O O O O O O O O O 0 Average Daily Total Digestible Nutrients Consumed Per Hundred Pounds Body weight by 28 day periods . Average Total Digestible Nutrients per Pound of Gain by 28 day periods . . . . . . . . . . . . . . 26 28 3O 31 33 35 \fl; j/r r ‘/ 1 /l v. ’ l .1 . '\ 1’ .. l .I' ”a \ _/ tie .. .~ 3* ‘pt' ' y! . ' ’O-i; M. e: JAE; i. it ’3' 31- a; ~- REVIEW OF LITERATURE Effect of Length of Feeding Period on Feedlot Performance, Finish and Carcass Yields Man has realized for some time that as an animal grows older and becomes fatter it grows at a decreasing rate and the amount of feed required for gain in liveweight increases. Studies to determine the nature of the factors responsible for this decreasing efficiency in fattening cattle were started in this country during the latter part of the nine- teenth century. Jordan (1895), at the Maine station, fed two pairs of steers of beef breeding, ages four to six months, rations differing vastly in protein content. One steer from each pair was slaughtered after seventeen months of feeding and the remaining steers were slaughtered ten months later. Jordan's observations were that digestive matter required to produce a pound of gain in liveweight increased with increased feeding. Daily gains of the steers increased until about the end of the ninth month of feeding, then decreased grad- ually. Several years later a similar experiment was conducted by Trowbridge,gt,gl., (1918), (1919) at the Missouri station. Three pairs of steers of Shorthorn breeding were maintained on different planes of nutrition. One steer from each pair was slaughtered and analyzed at later intervals. These ‘workers reported increasing cost of gains and decreasing daily gains as feeding progressed. The percentages of shin, shank, «can etc-l; 26.2-3- w .._ w 1 fi 1 .—_-—.’ .—..##n.-—- w . Mm..-” l "i... .l l ‘ : {'- ‘h .. ... . . .« r Jemn.l= " “fi' , ’ H I ‘ . ' t 3‘ . 4:91., Q a 1" ll - 2 _ round and neck decreased, while percentages of plate, rib. flank, kidney and kidney fat increased with increasing weight and fatness. Reports of Haecker (1920), of the Minnesota station, were based on observations made on 189 steers of beef breed- ing. Forty-nine of these steers were slaughtered and analyzed at various intervals from the time they weighed about 100 pounds until they weighed about 1200 pounds. Feed require- ments per pound of gain in liveweight increased with increas- ing weight, except for the interval of 500 to 600 pounds. Daily gains increased until the steers weighed about 600 pounds, after which the rate decreased. Mbulton,§tmgl., (1921), (1922), at the Missouri station, conducted an investigation similar to Haecker's using 59 steer calves of the Hereford-Shorthorn type. The Missouri workers observed a continuous decrease in efficiency during the four-year period in full-fed steers. Observations of the Missouri workers were almost in complete agreement with those of Trowbridge,§t,§1., (1919), that is, the rate of gain decreased and the cost of gains increased as feeding progressed. These workers also reported an increase in the proportions of loin, rump, flank and plate, while proportions of round, chuck, neck, shin and shank decreased with increas- ing age and fatness. Results obtained by workers at the Illinois station (Ill. Sta. Ann. Repts. 1927-28, 1928-29 and Bull,gt.§l., 1930) indicated faster and cheaper gains for calves fed for lhO - 3 - days than for calves fed for 200 days. The Illinois workers reported a rise in both slaughter and carcass grades as feeding continued. The percentages of cutting fat, flank, navel and brisket increased, while percentages of round and shank de- creased as feeding progressed. There were no appreciable changes in the percentages of rump, loin and chuck. Gramlich (1928), at the Nebraska station, made a study of the effect of age on the rate and cost of gain in steer calves, yearling, 2-year old and 3-year old steers. He reported that all cattle made faster and cheaper gains the first 100 days than the last 100 days of a 200 day feeding period. Gains made by the calves the last 100 days were cheaper than gains made by older cattle the first 100 days. Gramlich and Loeffel and U.S.D.A. workers (1927), at the Nebraska station, reported results obtained in a heifer feeding experiment showing increases in dressing percentages, slaughter and carcass grades, offal fat, and in the percentages of forequarter, rib and plate. Decreasing percentages of hind- quarter, round and shank were noted as feeding progressed. The percentages of loin and and udder remained rather constant. The same workers obtained similar results with cows, except that the percentage of hindquarter increased as feeding progressed due to accumulation of kidney and bed fat. Nelson (l9h5), (l9h6) analyzed data collected by workers at the Iowa station while studying the effect of age on effi- ciency in steers. He concluded that efficiency of feed utilization declined from the beginning of the fattening L h a period as indicated by gain in liveweight per hundred pounds of total digestible nutrients consumed by choice feeder steer calves. He stated that steer calves fed to good slaughter grade gained about 15.5 pounds in liveweight for each 100 pounds of nutrients consumed, compared with about 11A:- pounds gain in liveweight for calves fed to choice slaughter grade. This was a decrease in efficiency of about 31 percent. Nelson also stated that older cattle follow a similar trend, but in older cattle the decrease in efficiency was larger than in calves.‘ , Morrison (1950) in discussing the fattening process, .- said: "The fact that the proportion of fat in the gain made by an animal steadily increases during the fattening period is of much practical importance. It is the chief reason why the feed cost per pound of gain increases rapidly after an animal has become fairly well fattened. Such flesh contains much more fat and less water, and is correspondingly more expensive to produce. "The fat animal also needs a greater proportion of its feed for maintenance than the one which is not yet well fleshed, because of two factors: First, the maintenance requirement of a fat animal per 1,000 lbs. liveweight tends to be higher than for a thinner one; and second, the fat animal eats less feed per 1,000 lbs. liveweight, consequently having less nutrients left for meat production after main- tenance requirements have been met." -5; Effect of Length of Feeding Period on Physical and Chemical Carcass Composition Increases in growth are determined by either weights or measurements or by a combination of the two methods. These determinations are very simple to make and can be made numerous times without any harmful effects on the subject. However, in the determination of the physical and chemical composition of a carcass the animal must be sacrificed, the carcass separated into its various components, and for chemical analyses a uniform sample of certain parts, or of the entire carcass must be obtained. These factors have both complicated and limited the number of investigations of this nature due to the economics involved. Jordan (1895) was the first in this country to conduct an experiment of this nature. Based on observations made on two pairs of steers, he concluded that as feeding progressed the proportion of water in the carcass decreased and the proportion of fat increased; meat from older cattle furnished more water-free edible materials. Similar conclusions were drawn by Haecker (1920) based on the analyses of #9 steers. The analyses were made at various intervals from birth to about 1200 pounds liveweight. He also concluded that during the growing stage or from birth to 800 pounds liveweight, the protein stored exceeded the fat. and that above 800 pounds more fat was stored and less protein. Haecker's observations were in accord with reports of iMoultonlg§.§l., (1922) of the Missouri station. The Missouri hf‘*' - 6 - 'workers-reported that the first gains of thin cattle on restricted rations were 80 percent water, while the next gains were but 62 percent water. On the basis of observa- tions made on steers maintained on different planes of nutri- ' tion and slaughtered at various intervals, the Missouri workers concluded that the water content of the animal on restricted rations increased slightly until the animal reached 18.5 months of age, then decreased slightly. In calves that were placed on full-fed at approximately five months of age and maintained on this regimen over a four-year period, the gains became richer in fat and poorer in other constituents 'with advancing age and fatness until the last gains consisted of about 90 percent fat. Foster and Miller (1933), and.Hankins and Titus (1939) reported a relative decrease in the percentagescfi'lean, bone and moisture and a relative increase in the percentage of fat in cattle carcasses with increased finish. CalIOW'(l9#H), (19h8), (1950), of England, analyzed carcasses of 1%? animals (cows, steers, heifers, pigs and sheep) of various ages and degrees of finish. 0n the basis of the results of his analyses, he concluded that young animals fatten. more slowly and deposit less fat and more protein than older animals. With increasing age and fatness there 'was a percentage decrease in both muscular and skeletal tissue. The percentage of ether extract in the fatty tissue increased with increasing fatness. Fatty tissue increased with increased carcass fatness. Fatty tissue increased at a more rapid rate .A / I /, l g", ' / ' . ' - h . . fl ,II' // 1 r, .\ --~‘ ‘ ‘ I I ‘ \ . ‘q‘x. F" (t‘ I 1' I_ ‘ , . ‘t n . - l - ' ' ' 'k ' , ‘ ~ . i I ' " fl “ 'j _ I. 'A ‘ ' '. " - - ' ' . l , J,"- ‘3, , V _ ‘ ‘r 3 . b'vq- Q, . .. 5"“- 39- o g “ A _ , .._— .. - - “flaw-”mm ..7- in relation to bone as growth and fattening proceeded, how- ever, in the carcass of cattle there is always more muscular tissue than fatty tissue. wellington (195%) fed Holstein calves on three different planes of nutrition from one week of age until they were 80 weeks of age. Representative calves from each group were slaughtered at various intervals. He concluded that as such cattle increased in age the ratio of edible meat to bone increased. Age showed no consistent influence on percentage weight of muscle in the carcass. Effect of Sex on Feedlot Performance, Finish and Carcass Yields Investigations were started during the latter part of the nineteenth century to study the validity of the prevailing claim that open heifers were inferior to steers and spayed heifers as beef producers. Probably the first investigations of this nature were those of Wilson and Curtis (189%), (1896) of the Iowa station. These investigators ran two separate experiments comparing steers, open heifers and spayed heifers. Cattle used in the first experiment were high grade Shorthorn yearlings, with initial weights of 819, 751 and 718 pounds, respectively, for steers, spayed heifers and open heifers. Results of the first experiment supported the claim of steer and spayed heifer superiority, that is, steers made the fastest and most efficient gains, while open heifers made the slowest and most expensive gains of the three lots of v—W “ a 8 - cattle. Dressing percentages of the steers were the highest while those of the open heifers were the lowest. Yet both Open and spayed heifers yielded about one percent higher in the rib and loin cuts than steers. In the second experiment conducted by the Iowa workers, Hereford calves were fed separately for 1% months. Results of this experiment did not support the postulated open heifer inferiority. The open heifers made the fastest and most efficient gains. Steers and spayed heifers made practically equal and slower gains at about equal costs. Open heifers had the highest dressing percentages and those of the steers 'were the lowest. The results of cutting tests indicated that there was no material difference in the character, composition or quality of the meat due to sex. The heifers yielded more rib and loin than the steers and thus put more of their weight in the higher priced cuts. An extensive and detailed investigation in which the two sexes of beef cattle were compared was carried out at the Illinois station (Ill. Sta. Ann. Repts. 1927-28, 1928-29 and Bull gt,gl., 1930). High grade Hereford calves were used by these investigators. One group of steer and heifer calves was slaughtered after lhO days of full feeding and another similar group was slaughtered after 200 days of full feeding. The results of this investigation did not favor, in all respects, the claim of steer superiority. The Illinois workers found no significant difference in dressing percentages of steers and heifers slaughtered at the beginning of the experi- I 9 I ment nor after 140 days of feeding, although after 200 days of feeding there was a slight difference in dressing percen- tages in favor of the heifers. After 1%0 days of feeding, carcasses of the heifers graded higher than those of steers killed at the same time, but after 200 davs of feeding the reverse was true. workers at the Illinois station reported a higher percentage of cutting fat in feeder heifers than in feeder steers. However, in partly fattened and fat cattle there was no difference in cutting fat due to sex. Heifer carcasses cut out a larger percentage of flank and a smaller percentage of shank than steer carcasses. The percentage of “rib eye" was higher in steer carcasses than in heifer car— casses due to the higher finish of the heifer ribs. The Illinois investigators concluded that heifer calves reached a suitable market finish sooner than steer calves and, for this reason, heifers are better suited for feeding periods of 150 to 180 days. However, in the production of prime grade beef, they stated that steers usually bring greater profit because of the higher prices buyers will pay for them. According to Bohstedt (1927), of the Ohio station, when Hereford steer and heifer calves were fed a ration of corn, oil meal, alfalfa hay and corn silage for 15% days, steers made the largest and the more economical gains. 'Vaughan (1927), at the Minnesota station, obtained similar results by group feeding three lots of grade Hereford calves a ration of shelled corn, linseed meal, alfalfa hay and corn silage for 217 days. Steers, steers and heifers, and heifers comprised Lots 1, 2, _ 10 - and 3, respectively. He reported larger and cheaper gains for steers than for heifers. The mixed lot results resembled the average of the lots fed separately by sex. In order to determine how heifers compared with steers on different regimens, Trowbridge and Moffett (1932), at the Missouri station, fed high grade yearling Hereford steers and heifers separately. One lot of steers and one lot of heifers were full-fed for 182 days, and one lot of steers and one lot of heifers were given one-half the grain of the full-fed lots for IMO days and then full-fed on pasture for 168 days. According to the reports of these investigators, steers full- fed 182 days made larger and more economical gains than heifers treated in a similar manner. However, heifers yielded a higher percentage of beef and graded higher as slaughter cattle and as carcass beef. When calves were wintered on a limited amount of grain then full-fed on pasture for 168 days, steers showed greater margins for insurance, risk, interest and profit because steers made more economical gains and sold at higher prices. Results of a similar experiment conducted by Foster and Miller (1933), of the Missouri sta- tion, showed a larger percentage of forequarter in steer carcasses than in heifer carcasses. Steer carcasses contained a larger percentage of chuck than heifer carcasses, otherwise there were no appreciable differences in wholesale cuts attributable to sex. Hankins (1932) reviewed the results of various meat investigations conducted at various experiment stations, / I I L 11 - including Michigan, in cooperation with the United States, Department of Agriculture. He concluded that heifers reached a given finish at lighter weights than steers and usually exceeded steers in the amount of kidney and crotch fat. He found no significant difference in dressing percentage due to sex. Comparisons of dressing percentages and carcass yields of steers and heifers were made by Brown and Branaman (1935) at the Michigan station. One comparison was made on steers and heifers fed in equal numbers in mixed lots. The cattle were placed on feed at approximately seven months of age and fed liberally for 6% months, during each of three years. In this group of cattle the Michigan workers found slightly higher dressing percentages for heifers, although retail cutting records showed that steers yielded slightly more retail meat. In another experiment Brown and Branaman fed equal numbers of high grade steer and heifer calves individu- ally, the feeding beginning when the calves were about seven months of age. Calves were slaughtered at four different periods weighing approximately 600, 700, 800 and 900 pounds. In this latter test the heifers yielded slightly more retail meat. In both tests the percentages of chuck, round and shank were higher in steer carcasses, while percentages of rib, loin and rump were higher in heifer carcasses. Branamanpgt,§1., (1936), at the Michigan station, made a study of the relation of degree of finish in cattle to production and meat factors. Thirty-six steer calves and ,/ ' V , . . / ’ .‘ / I ‘ I ‘ A z ~ / .' . “- “a. ' .. I “pg 3 A 1a .‘73. __ v: ,7,, - 12 _ thirty-six weanling grade Hereford heifer calves were fed individually and slaughtered at four different stages of finish. Chemical analyses were carried out on the edible portion of the right half of each carcass. These workers grouped the calves according to the ether extract content of the analyzed right side. Six stages of finish were provided for, according to the following intervals of ether extract percentages: 12.0 to 15.9, 16.0 to 19.9, 20.0 to 23.9. 2#.O to 27.9, 28.0 to 31.9 and 32.0 to 35.9. The Michigan workers reported that heifers in the first and fourth stages were fed 10 and 5 days longer, respectively, than steers in the cor- responding stages in order to reach a similar degree of fatness. However, at each of the other stages of finish the steers were fed from 32 to #5 days longer than heifers. The Michigan workers made the observation that the aver- age feedlot weight increased through the series much more regularly than.was true with respect to time in the feedlot. The same situation was true in regard to the average total gain per animal. In every case a greater gain and consequently a heavier weight were necessary among steers than among heifers to produce similar fatness. WOrkers at the Mississippi station in cooperation with the United States Department of Agriculture workers (1937) made three comparisons that involved steers and heifers of various ages and fed similar lengths of time. In all compar- isons steers gained more rapidly and more economically than heifers. Differences in dressing percentages were small and in favor of the heifers. - 13 - There was a common belief that pregnancy was conducive to a more tranquil disposition and less bodily activity (Snapp 1935). On the basis of this assumption, pregnant heifers should be better performers in the feedlot than open heifers (Snapp 1935). This supposition was the basis for several investigations. An experiment of this nature was conducted by Snapp (1935), at the Illinois station. In this experiment he compared steer, open heifer and bred heifer yearlings. He observed retardation of growth in the region of the loin, hips and rump of pregnant heifers, while the greatest increases took place in the paunch and heart girth. Carcasses of bred heifers graded the highest of the three groups, while those of steers graded the lowest. Neither pregnancy nor sex had any significant effect on total gains. Dressing percentages of open and bred heifers were higher than dressing percentages of steers. The results of a later exper- iment conducted by Snapp and Bull (l9hh), at the Illinois station, supported the above data. They found that pregnant heifers were less active and had keener appetites than open heifers, nevertheless, there was no difference in the rate of gain and dressing percentages. The Illinois workers reported that the proportions of loin end, flank and round were signi- ficantly larger in open heifer carcasses than in carcasses of bred heifers, otherwise there were no significant dif- ferences in wholesale cuts. Open, spayed and bred heifers were compared by Hart 23 al., (19h0) at the California station. The observations of these -11...- 'workers were not in complete agreement with those of the Illinois workers. The California workers reported that the activity of open heifers was not serious and that they become less active as they fatten. These workers did not find that pregnancy in beef cattle increased feed consumption nor did its existence, up to the fifth or sixth month, seriously affect the dressing percentage of well finished cattle. The California workers concluded that no advantage was to be gained by spaying heifers that are going into the feedlot. Effect of Sex on Physical and Chemical Composition The assumption that sex may influence the physical and chemical composition of beef carcasses stimulated study along these lines. The economics involved and the difficulties encountered in separation and sampling have somewhat limited the amount of research conducted in this field. For this reason experiments of this nature are few and they have included only small numbers of animals. workers at the Illinois station (Ill. Sta. Ann. Repts. 1927-28, 1928—29 and Bull.g§‘§;., 1930) carried out physical analyses on carcasses of one steer and one heifer at each time, namely: the beginning of the experiment, after lhO days of feeding and after 200 days of feeding. They observed that carcasses of heifers contained a larger percentage of fat, the difference being greater in feeder heifers and de- creasing as feeding progressed. These workers concluded that up to 800 or 900 pounds liveweight, heifer calves put on fat -15- more readily than steer calves. However, this added fat was deposited as adipose tissue almost entirely, therefore at equal body weights, heifer calves possessed more visible fat than steers. In spite of this, steer calves had more intra- muscular fat. , Brown 9}; a]. (1937). Trowbridge gt 1.1,, (1937), Gramlich and Thalaman (1930), Gramlichlgt al., (1927) and Hunt gt $1., (1937) reported higher percentages of "eye" muscle, bone and tendon in steer carcasses. There were lower percentages of separable fat, ether extract and total edible portion in ribs of steers than in ribs of heifers treated similarly. The United States Department of Agriculture workers at the Iberia Livestock Experiment Station (1937) concluded that the higher content of fat in heifer carcasses could be demon- strated both by increased intramuscular and intermuscular fat when compared with steers. Hirzel (1939), in summarizing the results of meat in— vestigations that compared steers and heifers, concluded that after twenty-two months of age, in general. females were fatter than males. Nevertheless, the ratio of muscle to bone remained nearly the same for both sexes. The fat to bone ratio in young animals under fifteen months of age showed no difference between sexes, however. above this age the ratio was higher in heifers. . According to observations of Snapp and Bull (l9hk) bred heifer carcasses contained approximately 20 percent more separable fat, 5 percent less lean and 10 percent less bone - 16 ; than open heifer carcasses. The chucks, ribs, navels, short— loins, loin ends and rounds of the bred heifers contained a significantly larger proportion of fat than the corresponding cuts from open heifers. . A series of three experiments was inaugurated in 1933 cooperatively by the Michigan Agricultural Experiment Station and the Bureau of Animal Industry of the United States Depart- ment of Agriculture to study some of the production factors and carcass characteristics of fattening steers and heifers. Larger numbers of cattle were available than had been used in previously reported experiments or in tests since 1933 that have been reviewed herein from the literature. The data from these experiments were available for de- tailed analyses and offered a good problem for thesis material, however, it was not reasonable to attempt to complete analyses of all of the data for this thesis. The objectives of these experiments were as follows with regard to individually fed growing-fattening Hereford steer and heifer weanling calves: 1. To study growth and development 2. To study feed reduirements ‘ 3. To determine when cattle of the two sexes attain similar market grade A. To analyze the carcasses for: a. Cutting yields b. Physical composition .5. _ 17 - c. Chemical composition To study the wholesale rib cut: a. As a sample representing the carcass b. For cooking and palatability tests EXPERIMENTAL PROCEDURES Source of Calves and Feeding Methods The calves used in the experiment each year were grade Herefords raised on the United States Department of Agriculture Range Experiment Station at Miles City, Montana. Equal numbers of steers and heifers were selected for uniformity from one herd at the station and thus had similar breeding and care. The calves arrived by rail shipment in late October or early November and were started on experiment within about three weeks. Steer and heifer calves were full-fed individually. Each calf was confined in a small individual stall for about two hours at feeding time, night and morning. There was no water in the stall and it was not large enough for the calf to turn around. Heifers were released in one pen and steers in another after feeding time, where they had water and salt in a roomy inside pen, and access to an outside yard. Free choice feeding for each calf of hay in a rack and grain in a manger was attempted, but was not satisfactory. some calves selected the coarse feeds and some the fine feeds, so that similar performance could not be measured. A similar mixture was full-fed each calf thereafter, consisting of coarsely ground corn 6 parts, cottonseed meal 1 part, corn silage 3.5 parts and mixed alfalfa hay 1 part. Conditions forced minor changes at times, but all calves were handled and fed the same at any one time. - 19 _ Methods of Grading, Slaughtering, Cutting and Sampling Grading of the feeder and slaughter cattle and of the carcasses was done with a detailed chart formulated by a committee in the National Cooperative Meat Investigation group. All grading was done by the same committee of three members of the Animal Husbandry Department who had graded cattle for several years with members of the official grading committee of the Cooperative Meat Investigations. Slaughter cattle grades along with weights and gains are shown in Tables 1-h. The grades reported herein were those in use at the time the experiments were conducted and up to 1950, using the following abbrevations: F for Fancy, P for Prime, Ch for Choice and G for Good, with "I" or ”-" indicating "high" or "low" third of a grade. Weights were taken at 1% day periods and certain measure- ments were taken of the live cattle at the beginning and at the end of each trial, and of the carcass. Feed was withheld after the morning feed of the day before slaughter. but water was available. Cattle were slaughtered at four stages of fattening and these stages were called kills. Each kill was completed in one day with hot weights off the killing floor and cold weights were taken #8 hours afterward. Weights were taken for each part of the offal. All parts of the digestive tract were weighed, emptied, washed and reweighed. The diges- tive content was determined in this manner and when subtracted from slaughter weight the empty body weight was obtained. :- / ‘ . ‘ I ‘I ' - , s L‘ . l . ‘ f I I. ‘ ' ‘I‘ . ) A‘~\ fffifiiumfl”‘* - "w~ l . , a . 9‘ . k . A .fi.‘ " . ‘_ : . . :7.— ; 20 - Cutting and separation records on each right half were made within the next three or four days after the #8 hour cold 'weight. The Chicago Method of cutting with details recommended by the Cooperative Meat Conference were followed. One man made all wholesale and retail cuts, and one man checked the completeness of the separation of each cut into bone, fat and lean. The rib cut from each side of the carcass, including ribs 8-12, and a ground and mixed sample of each separate component (fat and lean) of the right half were sent to the United States Department of Agriculture Research Station at Beltsville, Maryland for analyses. The wholesale rib cuts along with the samples were packed with liberal amounts of crushed paper in a large insulated box and cool temperature, without freezing, was maintained by the use of a small amount of dry ice. _ 21 - Table 1. Performance of Kill 1 Steers and Heifers STEERS ' Calf Days Initial Final Total Average Slaughter Number on weight 'weight Gain Daily Grade Feed lbs.l, (lbs.) (lbs.) Gain (1bs.) Trial 1 1n 126 #00 628 228 1.81 M J 16 126 389 659 270 2.1% G / 18 126 399 568 169 1.3% G Trial 2 16 105 332 6g1 269 2.56 e - 23 105 5 5 8 183 1.7% G 2 105 %63 688 225 2.1% Ch - Trial 3 16 132 %09 71 30% 2.30 e 17 132 325 662 3%1 2.58 Ch 39 132 3%6 601 255 1.93 Ch - Average, 9 Steers 121 389 638 2M9 2.06 e HEIFERS Trial 1 % 126 333 550 197 1.56 G - 6 126 702 298 2.37 Ch - 13 126 380 600 220 1.75 G / Trial 2 105 %%2 69 25 2.%1 Ch - g 105 388 59. 206 1.96 G l 11 105 373 577 20% .9M 0 Trial 3 ' 1+ 132 364. 691 327 2.%8 Ch 6 132 311 596 285 2.16 Ch - 11 132 326 597 271 2.05 G - Average, 9 Heifers 121 371 622 251 2.08 G / ‘ .1 ‘ . / “\i If i c' u .. , 1.: [g 7‘ ' ‘ - ‘ ‘ " "m r I : e ‘ ' 7} 2 A }‘ I: { 3147:3337; ' , ' L 1 r .- fl. I... I 2"..‘ VL‘ _ ~ . . '~ ‘1 "a"? . .2 - h ; ‘ p- 5 . , .-l e - .. <. A ‘ ‘ -C n-l' . .., , ‘ - 22 - Table 2. Performance of Kill 2 Steers and Heifers STEERS ‘ Calf Days Initial Final Total Average Slaughter Number on 'Weight ‘Weight Gain Daily Grade Feed (lbs.2 Slbs,), S1bs.) Gain L1bs.) Trial 1 21 175 %l% 7%7 353- 1.90 Ch 28 175 76 756 3 0 . 2.17 Ch - 2 175 01 773 372 2.13 G ' Trial 2 17 15% 33% 716 322 2.09 e x 26 15% 1 #2 301 1.95 Ch 27 x 15M %19 13 39% 2.56 e # Trial 3 1% 182 396 818 %22 2.32 Ch / 13 182 3%1 726 333’ 2.12 G X 2 182 3%0 780 2.%2 Ch Average, 9 Steers 170 391 763 372 2.19 Ch - HEIFERS Trial 1 8 175 %00 706 306 1.7 Ch 10 175 3%5 6%9 30% 1.73 G 11 175 369 713 3%% .97 Ch - Trial 2 1 15% 6% 701 3 7 2.19 Ch / 7 15% 30 773 3 3 2.2 Ch 12 15% 399 683 28% 1.8 Ch - Trial 3 1 182 3 8 71 373 2.05 Ch / 5 182 3E6 775 %29 2.36 Ch % 12 182 336 631 295' 1.62 G K Average, 9 Heifers 170 370 705 335 1.97 Ch Table 3. Performance of Kill 3 Steers and Heifers a 23 _ STEERS Calf Days Initial Final Total Average Slaughter Number on Weight Weight Gain Daily Grade Feed gfilbs.) _les.) (lbs.) Gain (lbse) Trial 1 ' ' ' 17 22% 66 78% %18 1.87 P - 22' 22% 15 866 %51 2.01 Ch - 27 22% 392 821 %29 1.92 G 7 Trial 2 18 203 370 821 %51 2.22 Ch - 2%- 203 77 788 %11 2.02 Ch - 25 203 15 906 %91 2.%2 Ch Trial 3 1 2%? ‘377 831 %5% 1.8% Ch 18 2%7 339 g93 %5% 1.8% G I 20 2%? 357 %3 %86 1.97 Ch 7 Average, 9 Steers 225 379 828 %%9 2.00 Ch HEIFERS Trial 1 . 3 22% 389 751 362 1.62 Ch 5 22% 372 710 E38 1.51 P - 7 22% 373 812 39 1.96 Ch # Trial 2 a 203 392 78% 92 1.93 P 203 395 805 10 2.02 Ch 15 203 323 735 %12 .03 Ch % Trial 3 0 2%7 323 695 72 1.51 Ch - 3 2%? 325 80% 79 1 .9% Ch / 9 2%7 3%6 83% %88 1.97 P Average, 9 Heifers 225 360 770 %10 1.82 P -* * Significant at the 5 percent level. ! / / / \ I .l 'I ‘ "‘"" l 2 I‘\'-' h 5"," in.” ‘ 3w ' ‘ v. x I _ Li ‘ i: " ~ '14 L~dlb ‘1. ‘ .- - 2h - Table %. Performance of Kill % Steers and Heifers STEERS Calf Days Initial Final Total Average Slaughter Number on Weight weight Gain Daily Grade Feed (lbs.) (lbs.) (lbs.) Gain Libs.) Trial 1 19 273 378 889 511 1.87 Ch 20 273 398 92 29 1.9% P - 2% 273 375 82 53 1.66 G 7 Trial 2 19 259 338 968 610 2.36 P 22 259 2 9g6 53% 2.06 P - 29 259 377 8 6 509 1.97 P - Trial 3 0 29% 329 8%5 516 1.77 Ch / 19 29% 368 989 621 2.11 Ch 21 29% 387 1009 622 2.12 P - Average, 9 Steers 275 369 92%** 5%5 1.98* Ch 7 HEIFERS Trial 1 1 273 371 800 %29 1.57 - 2 273 370 731 61 1. 2 Ch - 9 273 360 819 59 . 8 Ch Trial 2 6 259 71 872 501 1.93 P 10 259 19 1037 618 2.39 P - 13 259 366 822 %56 1.76 P Trial 3 2 29% 311 876 65 1.92 Ch / 7 29% 385 867 £82 1.6% P 8 29% 361 782 %21 1.%3 Ch Average, 9 Heifers 275 368 8%5 %77 1.73 P - * Significant at the 5 percent level. *’ Significant at the 1 percent level. RESULTS AND DISCUSSION Data were tabulated in Tables 1 to % for individual cattle showing weights, gains and slaughter cattle grades. The cattle were grouped by kills and sexes so that comparisons may be noted. . ‘ The slaughter grade of the cattle was used in deter~ mining the time for slaughter of each kill. An attempt was made to space the kills so that the heifers would average the same stage of fatness as the steers in the succeeding kill. The slaughter grades listed in the last column of Table 1 indicate reasonable success. It was necessary to divide the cattle of each sex at the time of the first kill so as to have representative cattle for each kill. There were, of course, variations among cattle of each group and it seemed advisable to shift an animal occasionally as killings took place to, keep the groups representative. Further comparisons and discussions of grades, separable fat of the carcass and ether extract content of boneless meat of the carcass are made later in the manuscript together with comparative tables that will show the cattle to have been killed at rather closely matched degrees of fatness. There were slight differences in lengths of feeding periods, the differences being in Trial 3, and they were due chiefly to coordinating work schedules at East Lansing and Beltsville. The average number of days on feed were 121, 170, 225 and 275 days for cattle in Kills 1, 2, 3 and %, respectively, with the difference between kills being %9, 55 and 50 days. .u n. t... us o I. 1‘ _. \wv. mmx m3 SI N: vw mm. 8 ex 43 In!!! -fi:ttl&|lz4.-i. - _ -- .qulii 1.1.4155?1.41.2.--315114 I. - _l 1 1...... 0 Seance hmc mm .8. .. _. \. 3:303 moon amended .. \\. H 0 —FuWfim ‘\.- \.\\\ ..L. A.) Q \\ \\\ . x... \. .x\\. \ \\ \ .\\ \\\\ \ \I \ \ \\ \ \-\ \ .. mHQMme l t... In I mfimmpw _ :31}- _ ..E _. w - 7., :5 11.2.: _ I i ‘ .. hinéui‘ ~-~ . _ 27 - The results shown in Figuresl to 3 were based on 28 day averages of all cattle used in the three experiments. The number of cattle in each sex was reduced by nine cattle at each kill, therefore, the reliability of all measurements decreased as the killings progressed due to the decreasing number of cattle representing the right hand segment of these curves. On the average the steers used in these experiments were slightly heavier than thetunfers at the beginning of each experiment, although, as seen in Tables 1 to %, several heifers weighed more than several of the steers. Figure 1 shows that the weight advantage of the steers increased as feeding progressed. The average feedlot weights of the steers were 16, 58, 58 and 79 pounds heavier than that of the heifers after 121, 170, 225 and 275 days of feeding, respectively. These differences merit consideration, however, due to large variations in individual weights and the small number of cattle, the difference due to sex reached significance only when cattle were fed for 275 days. Figure 2 shows that cattle of both sexes had about the same daily rate of gain the first 8% days of feeding, although after this period steers made the fastest gains. During the period between 56 and 168 days on feed cattle of the two sexes gained at rather constant and parallel rates. Following the 168 day weigh period, a sharp decline in rate of gain for cattle of both sexes occured. The heifers continued at the slow rate of gain, while the steer gains were lower than earlier l(\_ k) tlll.‘ «oedema use mm an mefimo enema amended. N onsmfim ..Lll: _ _ whomwom I i i memopm Ill \3 h 2‘ 40m ' "n a ' - . ,l / I]. 1 .’ / .. . "N...” %‘~’ at“; ' .. ' ‘ Em" ' L; ‘ -~- g I I 3' .7 _:-A Mr ... *I. _ 29 _ in the feeding period but they continued to gain at a rate faster than that of the heifers. When cattle of similar fin- ish are compared by referring to Tables l-%, and comparing each kill of heifers with the succeeding kill of steers, the difference between the rate of gain for the two sexes is very small. Daily gain per hundred pounds of body weight in Figure 3 followed a pattern similar to that of average daily gains, except for an earlier drop and a more even drop at a.faster rate. During the first 112 days of feeding, gains averaged over O.% pound daily for each hundred pounds that the cattle 'weighed, which was about twice the rate during the time after 196 days of feeding. Heifers made larger gains per unit live ‘weight than steers during the second and third 28 day feeding , periods because daily gains made by heifers during these periods were about equal to those of the steers and the heifers were of lighter weights, but heifers dropped more rapidly thereafter. The rate decreased in cattle of both sexes after 56 days of feeding with cattle of the two sexes following a similar pattern. In order to express feed consumption in one figure the results were computed on the basis of total digestible nutrients (TDN) from values in Morrison's text "Feeds and Feeding" (1950). The daily TDN consumption of the steers and heifers shown in Figure %, followed a very close parallel to each other during the first 112 days, with an increase of near 50 percent from the 28th to the 112th day. After the first 112 .\ «a -. -.-.- x. a w - 6.x m6 03 x x 6 - I. .- .- 1 _ _ _ m _-1-r .- .- - _ W moofinoo hen mm an ) named: aeom messed 8855 \ \ I II I nee 5mm haw-en ommambq \.\ x- ..- ..- \ m enema / Ill-‘11} IL. 288m I .- mneopm 3%- _._-..-., .3 l. .- [Err-i 7.: - _ 3-7-.-. _ e _ --.. . -C‘-FL.V H. ‘I ‘ ~o- *-" 352 me he no 855980 mung acorn oHnHmmmen H.309 Enema 38.815. in chew-E 0.... 989-hm: mhmwpm I “ fin I ./ . .. l I . '1“ . I / I u ‘ . ' ' \‘ I ‘ ‘ ; b . I . » hear 8 —rs ~ 1 1 Jam " ' ' '-" .1 .— q... 7 - ' ' l. 'r 4a. . h. P ‘- .- , .‘i an , . - l. 1': 1 ‘ . .~ a.» A“ A , . «- - 32 a days of feeding the steers ate more than the heifers and the difference due to sex increased as feeding progressed. The large increase in daily TDN consumption between 56 and 112 days of feeding was due in part to the cattle having become adjusted to the environment, and there also was an increased energy demand due to the rapid growth that took place during these stages. After the 1%Oth.day of feeding daily TDN con- sumption decreased_for cattle of both sexes. The daily TDN intake of the steers was increasingly greater than that of the heifers after 112 days of feeding for two reasons, namely; higher maintenance costs due to heavier weights and the in- creased growth rate of the steers above that of the heifers. Figure 5 shows that during the second 28 day feeding period TDN consumed per hundred pounds live weight decreased for cattle of both sexes, the decrease being larger for steers. Between 56 and 112 days of feeding there was an increase in TDN consumption per hundred pounds live weight in cattle of both sexes. Heifers showed the largest increase during this period, when they were of lighter weights and, as shown.in Figure %, there was a'very small difference between the sexes in daily TDN consumption. The increase for all cattle follows less rapidly the large increase in daily TDN consumption as shown in Figure %. Cattle fed beyond 112 days showed a marked and continued decrease in TDN consumption per unit of body weight. . Total digestible nutrient requirements per pound of gain ‘was one method used to measure efficiency in these experiments. ll. \l. moo-Eco knew mm ,3 3363 zoom menace osmosom nod oesomeoo mpeofinpsz oHpfipmomen deuce edema omenoed L. II-I-uu-I.|J/ m madman _ xx // m /, - / If. i / . /. IINn. / 0 . / _/ / x lo / \l l \\ 11.1: / \ ,/ \\ \\ / . \\ gonadal...- ..i- /(\- memopm ::::i 113,-- --.W.7-----lh111-----7--- - _ - -7 ----.--....7 : _ _ a. .l - I / " ' s ‘ z - u / Q . ‘ ' 7 [3.1- ‘ , ~ ' - I'v— ' ‘ 4 .- R- ' . 4 “lj. ‘ ‘ '-. .. ‘ 4 , m . ' r--'a-_. ‘ - .1 / 2 - 3h ; Although the validity of this method of measuring efficiency in livestock is criticized by many investigators, especially those who feel that efficiency in livestock Should be measured in terms of units of human food, nevertheless it is still the most practical method of measuring efficiency in livestock. An examination of Figure 6 and Table 5 will reveal a very small difference in TDN requirements per pound of gain due to l . sex during the early stages of feeding, although during the later stages of feeding heifers required more TDN per pound a. of gain than steers. Figures 2 and % show that heifers made smaller gains and ate less nutrients during the later stages of feeding. Heifer number 8 of Kill %, Trial 3 lost nine pounds between 196 and 22% days of feeding while several other heifers made very small gains. These facts account for the high point in the heifer curve in Figure 6 at the 22% day period. The results tabulated in Table 6 show that for cattle of similar finish the TDN requirements per pound of gain were slightly higher for steers than for heifers but not significant. These results indicated that degree of finish or added weight had a greater effect on efficiency in fattening cattle than sex. Another comparison was made using a predicting equation derived according to Fisher's Statistical Methods for Research Workers, %th edition, pages1%2-150. Total digestible nutrients required per pound of gain were predicted from average body weight and ether extract content of the carcass boneless meat. The predicting equation was found to be ye -O-O95X / .22125 0.333 .. 1 _ - .. .- -I.w.--_:. i- 110»... was. .41.. pm. me. 7 a 1 nil-11..-.-. i... -- all-ii- - n moOHeoa moo mm an memo mo women are _l mpeoEp-oz cap-newsman Hen-ea 09395. M w chow-E q. l l. m \ \ .7 7/ \ l. \ \ _ / m \ l. / \ \ m.- / \ /\ . / / / / .l / l / \ / \ / \ x i I / \ / \ mnemfiom l l I \\ L monmpm III /\ \ _ i Isl p b _ _ lialb F1111!!! ..- u \/ I O ___1_._/ -Wo ‘io \ v---L _. a I ~36- Total Digestible Nutrients per Pound of Gain * Significant at the 5 percent level. ** Significant at the 1 percent level. Table 5. Performance of Steers and Heifers (By Kills) Number Days Final Average on Weight Daily Gain Sex Cattle Feed (lbs.) (lbs.) (lbs.) Steers, Kill 1 9 121 6382.06 ' %.6 " Heifers, Kill 1 9 121 622 2.08 %.6 Difference ' Steers over Heifers 16 -0.02 0.0 Steers, Kill 2 9 170 763 2.19 %.8 Heifers, Kill 2 9 170 705 1.97 %.9 ‘Difference Steers over Heifers 58 0.22 -O.l Steers, Kill 3 9 225 828 2.00 5.0 Heifers, Kill 3 9 225 770 1.82 5.3 Difference Steers over Heifers 58 0.18 -O.3 Steers, Kill % 9 275 92% 1.98 5.% Heifers, Kill % 9 275 8%5 1.73 5.8 Difference Steers over Heifers 79** 0.25* «10.11"I Averages Steers 36 790*‘ 2.06* 5.0 Heifers 36 736 1.90 5.2* 1 I I ‘- .i. 1' ‘ ‘ D- '. I . U ‘ S: “ fl$flifik "‘5’ .;. ' i 1 1 1 .5; i;- 1 1 1 1‘ .. 3 .- ‘ 1 . _ ‘ ' . ‘- an; .. 4 38 - lvhen y equals pounds of TDN per pound of gain, x equals average body weight, and z equals ether extract content of carcass boneless meat. A test was made in order to determine whether or not the magnitude of the difference between the constants -0.095'and 0.221 was significant. The t value in this case was 2.95 which was highly significant. Therefore, ether extract content of the carcass was better for predicting total digestible nutrients required per pound of gain than final body weight, or in other words the fatness of the car- cass was a better measure of nutrient requirement than was final body weight. Slaughter Data Averages of slaughter weights, shrink from feed lot to slaughter, empty body weight, and percentages of digestive contents and caul and ruffle fat are shown in Tables 7 and 8. All cattle were weighed for three consecutive days before slaughter and the average of these weights was taken as the final weight. On the day the third weight was taken the . cattle received no evening feed, but had access to water. They were slaughtered the next day with one weight being taken just before slaughter. The difference between final feedlot weight and slaughter weight was termed "shrink, feedlot to slaughter." The shrink from feedlot to slaughter did not follow any definite pattern, neither in sexes nor in groups of cattle fed for different lengths of time. The season of the year and the1amount of water consumed may have had more influence on shrink than either sex or the length of the feeding period. .{ 1‘1 II III III Ill 1“ ‘ Table 7. Number Days - 39‘- Slaughter Data (By Kills) §e z Cattle Feed Weight) les.) Steers, Killl 9 Heifers, Kill 1 9 Di ff erenc e , Strs. over Hefs. Steers, Kill 2 9 Heifers, Kill 2 9 Difference, Strs . over Hefs. Steers Kill 9 Heifers, Kill 3 9 Difference, Strs. over Hefs. Steers, Kill A 9 Heifers, Kill H 9 Difference, Strs. over Hefs. Averages ' Steers 36 Heifers 36 Shrink ' Aver. from Digestive Empty Caul and Feedlot Slaughter Content Body Ruffle on (% Final weight (% slaug. weight Fat (% wt.) ‘ (lbs .) Slaug. wt.) 121 1.9 625.7 9.9 56h.0 2.9 121 3.7 599.8 9.3 544.1 3.2 -1.8 25.9 0.6 19.9 -0.3 n 170 3.8 73h.3 10.5 657.3 3.8 170 3.5 679.8 9.8 611.0 3.8 0.3 59.5 0.7 46.3 0.0 225 2.7 805.5 10.1 72H.h 3.7 225 2.7 750.4 ‘ 9.6 678.8 9.0 0.0 55.1 0.5 #5.6 -0.3 275 3.5 891.9 9.1 810.7 h.3 275 3.5 816.n 8.8 7h5.0- h.5 0.0 75.5** 0.3 65.7*=o.2 3.0 76n.1** 9.9 689.1**3.7 3.3 711.6 9.n euu.7 3.9 ** Significant at the 1 percent level. ‘ I / Ar / _._1:1;. .a I i7+*?*‘ - no - Table 8. Slaughter Data (Cattle of similar finish). 'munm . . Aver. from Digestive Empty Caul and Number Days Feedlot Slaughter Content Body Ruffle of on (% Final weight (% slaug. weight Fat (% Sex Cattle Feed ‘Weightz Slbs.) wt.) (lbs.) Slang. wt.) Steers,.‘ . . . . . . Kill 2 9 170 3.8 73%.3 10.5 657.3 3.8 Heifers, x111 1 9 121 3.7 599.8 9.3 599.1 3.2 Difference, Strs over #9 0.1 ' 134.5** « 1.2 113.2**0.6 Hefs. ‘ Steers, Kill 3 9 225 2.7 805.5 10.1 72h.h 3.7- Heifers, Kill 2 9 170 3.5 679.8 9.8 611.0 3.8 Difference ' Strs. over 55 -0.8 125.7** 0.3 113.#*!0.1 Hefs. Steers Kill A 9 275 3.5 891.9 9.1 810.7 h.3 Heifers, Kill 3 9 225 2.7 750.1 9.6 678.8 h.0 Difference Strs. over 50 0.8 1%1.5** -0.5 131.9’*0.3 Hefs. . Averages Steers 27 3.3 810.6** 9.9 730.8**3.9 Heifers 27 3.3 676.7 9.6 611.3 3.7 ** Significant at the 1 percent level. v w. ‘7‘“ 2" ,,— .— ,_._ 'w-v, - 41 ; Shrunk weights at time of slaughter showed that steers ‘were 25.9, 5#.5, 55.1, and 75.5 pounds heavier than heifers after 121, 170, 225, and 275 days of feeding, respectively. iHowever, due to the large individual variations in weight, the difference due to sex reached significance only when cat- tle were fed for 275 days as shown in Table 7. When cattle of similar finish were compared the results showed that steers were significantly heavier than heifers at the end of each feeding period. This fact sustained the generally quoted report that heifers finish at earlier ages and lighter weights than steers. Differences of 126 to 142 pounds in shrunk weights between steers and heifers, with #9 to 55 days difference in feeding periods gave steers a signi- ficant weight advantage in cattle with similar finish. The digestive tract was weighed both full and empty and the difference between these two weights represented the contents of the digestive tract, allowing empty body weight to be calculated. The digestive content as percent of slaughter 'weight was slightly higher in steers than in heifers, although the difference due to sex was too small to be significant at the levels used in testing differences. The percentage of digestive content did not vary con— sistently with finish or weight. The results indicated a slight decrease in the percentage digestive content with increasing fatness, except for the first kill cattle which had a lower content than the second or third kills. '.- _.V. . x E .» . I. ~ " \‘b' ‘ \Q .m.‘ y , . 3‘ ”My ' .‘f 4'}, I. a. . ‘ ’ .., #- ’ E.‘. «Qg 1 J ,t'a . - t y ‘ 77 — ———u— .—__u.-..—— a ha a Net or empty body weight was obtained by subtracting the weight of the contents of the digestive tract from slaughter 'weight. The differences between sexes in net body weight followed the same trend as slaughter weight, that is steers, on the average, were heavier than heifers. The net body ‘weight advantage of the steers over the heifers was less than the difference in slaughter weight because steers had a slightly higher percentage of digestive content than heifers. The dif- ference in net body weight due to sex was significant at the 1 percent level only when cattle were slaughtered after 275 days of feeding. ‘When compared at stages of similar finish, differences of 113 to 132 pounds were significant between steers and heifers. In order to determine whether or not heifers deposited a larger proportion of fat on the digestive organs than steers, the caul and ruffle fat was removed and the results were ex- pressed as percent of slaughter weight as shown in Tables 7 and 8. The percentage of caul and ruffle fat was higher in heifers at all stages of fattening except Kill 2, the dif- ferences due to sex were not significant at the levels used in testing differences. The results in Table 8 show that when cattle of similar finish were compared the differences in percentage caul and ruffle fat were negligible. The percentage of caul and ruffle fat was significantly higher in cattle slaughtered after 170 days of feeding than in cattle slaughtered after 121 days of feeding. There was no significant difference in percentage caul and ruffle fat .v ’ A~- o 03 o. ,3 57' 3301323 :MMH mm NH HOr-l 4: Hm ggvpoiooo '10.0. ..9 “I"! “1‘21 “29“! “30' ---c.: 3‘0 . more 30.11? c300 090 ('30 ooo ooo 0°? 900 3 (0'6 U)‘ " s4 00 H ex 0H -0\\oo mmo r-lr-lI-i (fir-l oooo HNN 5'55 "‘N‘ 0? 940301 6'... .0. .0. .Q 0.. 0.. 0.. ...$u. g3 '4 m ;.r-l'.:_1_-I.:l- HNr-l :20: mm (mm—q 4-3;:- mu‘r" OHH m 09' m1 2 o 0‘ “ 7mm“ N‘f‘O \OO\H com (mom moul- .:I-°“° (“l-‘00 o H 5 «P‘ooo ooo o.o oo ooo o0. 0'. "'.C 3“ H m ngm HNF'lhd‘ChN NN Nip; :5;- tht-l Or-IH .p 13‘” .3 9 9 "‘ ‘23 ..s s g e‘ .G 49 43 em '3 a: - E n +9 0 m «5 g 0 U! m 0 ' In H {D m q-t com o H o ‘H Hg 5 n 6 0H 0 a}? '~ 0 aw e ends passage sfi efigsefigeefis pfise .-| m .0 gmeonmoommeo'gmo meoomoo-pwoo “SO-H 49 >= 5 hnmgeqmemnm hnnmgmsmnmwmu‘n '5“ mm as as oo o H .4 .c: 'c’ e. n 2. mm on: .4 a. a: o E: m * v .61... In cattle of similar finish the meat to bone ratio ‘was larger in heifers than in steers. The difference in the meat to bone ratio, attributable to sex. was significant when steers slaughtered after 225 days of feeding were compared with heifers slaughtered after 170 days of feeding. These results indicated that the meat to bone ratio in cattle car- casses was dependent on both degree of finish and sex. ” The»meat to bone ratio increased in cattle of both sexes as feeding progressed. Physical Composition of“Wholesale Cuts . The wholesale cuts of the right half of each carcass were separated into fat, lean and bone. lverages of the m physical composition of the wholesale cuts are shown in Tables 17 and l8. The results are expressed as percentages of the cold carcass weight. . _ _ _ _ Fat is the most variable constituent in_the carcass and in the wholesale cut, and the percentages of lean and bone vary inversely with the percentages of fat. Fer this reason, fat and its variations were given the most consideration in the following discussion. _ _ There was no significant nor consistent difference in the proportion of round fat in the carcass due to sex. 'With increasing fatness the percentage of round fat increased in cattle of both sexes, except when heifers slaughtered after 225 days of feeding were compared with heifers slaughtered after 170 days of feeding. - -65-'- In cattle of similar finish round fat comprised a slightly larger percentage of steer carcasses. The difference in the proportion of round fat was largest, but not significant when heifers slaughtered after 225 days of feeding were compared with steers slaughtered after 275 days of feeding. The percentages for round lean and bone were larger in steer carcasses than in heifer carcasses slaughtered at the same time. The difference in the proportion of round lean due to sex was too small to be significant at the levels used in testing differences. However, the bone in the rounds of steers accounted for a significantly larger prOportion of the carcass than in heifers, except in cattle slaughtered after 275 days of feeding. It can be seen in Table 18 that there was very little difference in the proportion of rump fat when cattle of . similar finish were compared. There was a consistent increase in rump fat with finish indicating that degree of finish had more influence than sex on the proportion of fat in the rump cut. . _ ‘ Sex did not have any consistent or significant effect on the proportion of lean in the rump. _Neither sex nor degree of finish had any appreciable effect on the percentage of rump bone in the carcass as shown in Tables 17 and 18. Loin fat in heifer carcasses comprised a significantly larger proportion of the carcass than in steers when cattle were slaughtered after 121 and 225 days of feeding. The ; 66 a proportion of loin fat was larger in heifer carcasses than in steer carcasses when cattle were slaughtered after 170 and 275 days of feeding, although the difference due to sex was not significant. ' Results tabulated in Table 18 show that the difference in percentage of loin fat was not consistently different in carcasses when cattle of similar finish were compared. Loin fat accounted for a higher percentage of the carcass in cattle of both sexes as feeding progressed. The largest increase in the proportion of loin fat took place between 121 and 170 days of feeding, which indicated that fat deposition in the loin took place at a faster rate during the earlier —stages of feeding. On the basis of these results it is safe to assume that the proportion of fat in the loin without the kidney was largely dependent on the degree of finish rather than sex. ‘ . There was no significant difference in the percentage of loin lean attributable to sex, although at similar finish heifer loins contained slightly more lean at each stage when cattle were slaughtered after 121, 170 and 225 days of feeding. With cattle of similar finish the difference in the propor- tion of loin bone was neither consistent nor significant. The percentage of flank fat in heifer carcasses was significantly larger in all kills. In cattle of similar finish the percentage of flank fat was significantly larger in heifer carcasses than in steer carcasses, when steers of Kill #‘were compared with heifers .’l_ / . .lll : . I". I, . '. _1. . I??? ' 'c..: ‘ ~. .1, '1' t ' "7 11% II ' ' " l'r y . ‘ . . r 'j . w _ . r .. ' "1' ‘- _ n' I . -- ‘ ~.. .5“ . - 67 - of Kill 3 and for total cattle of each sex as shown in Table 18. The proportion of flank fat in the carcass of both sexes increased as feeding progressed. These results showed that both degree of finish and sex:influenced the proportion of flank fat in the carcass. v" The percentage of lean in the flank was not affected considerably by sex or degree of finish. The wholesale rib fat in heifer carcasses comprised a significantly higher percentage of the carcass than in steers when cattle were slaughtered after 121 days and 225 days of feeding. After 170 and 275 days of feeding the wholesale rib fat constituted a larger proportion of heifer carcasses, but the difference due to sex was not significant. There was practically no difference due to sex in the proportion of wholesale rib fat in the carcasses of cattle of similar finish. The proportion of wholesale rib fat in the carcass increased in cattle of both sexes as feeding progressed. These results indicated that the proportion of wholesale rib fat in the carcass was largely dependent on the finish of the cattle. There were no significant differences in the proportions of whOIesale rib lean or bone due to sex. There were no significant differences in the pr0portions of plate or chuck fat in the carcass due to sex, but heifers averaged higher at each kill. In cattle of similar finish, steer chucks and plates contained more fat at each stage, but the difference was not significant. ‘ “1 - 68 ; Both the proportion of chuck fat and the proportion of plate fat in the carcass increased in cattle of both sexes quite rapidly as feeding progressed. Steer chucks contained more lean at each kill, the dif- ference being significant at the first and third kills. In cattle of similar finish, differences were not significant. Steer chucks contained a higher percentage of carcass bone, 'with significance in the first three kills. At similar finish, steer chuck bone was slightly higher but significant only at the middle stage. The percentage of plate bone was higher in steer carcasses both when cattle were matched by kills and finish. The percentage of plate lean in the carcass was higher in steer carcass when cattle were compared by kills but higher in heifer carcasses when cattle were matched by finish. The edible portion of the shank is very small and changes but little during the fattening process. Therefore, only the bone of the shank was considered in this discussion. The proportion of shank bone accounted for a significantly larger proportion of steer carcasses than of heifer carcasses in all kills. Differences were larger when cattle were slaughtered after 170 and 225 days of feeding, and after 225 days of feeding the difference in the preportion of shank bone decreased. In cattle of similar finish the preportion of shank bone in the carcasses of steers was significantly larger than in those of heifers. These results indicated that, generally, s 69 - Table 19. Chemical Composition of Carcass Boneless Meat. (Results are expressed as percentage of carcass boneless meat Wt.) Number Average of Days on Ether Sex Calves Fegdr Extract Protein Moisture Ash ;;;;rs, .. ...w .. . .... ... .. ‘ _.. . Kill 1 9 121 21.2 17.5 60.0 0.9 Heifers, Kill 1 .9 121 27.2 15.9 55.6 0.8 Difference Strs. over -6.0** l.6** h.%** 0.1 Hefs. Steers, Kill 2 9 170 28.9 16.0 53.9 0.7 Heifers, Kill 2 9 170 30.5 15.3 52.3 0.8 Difference * Strs. over -1.6 0.7 1.6 -0.1 Hefs. Steers Kill 9 225 29.0 15.9 53.9 0.7 Heifers Kill 3’ 9 225 31+.o 15.0 1+9.8 0.7 Difference Strs. over -5.0** 0.9" M1" 0.0 Hefs. Steers Kill 3+ 9 275 33.6 15.0 50.1 0.8 Heifers, Kill # 9 275 3u.9 1h.7 u9.1 0.8 Difference _ Strs. over -l.3 0.3 1.0 0.0 Hefs. Averages Steers 36 28.2** l6.l** 5%.5'”I 0 8 Heifers 36 31.7 15.2 51.7 0 8 * Significant at the 5 percent level. ** Significant at the 1 percent level. , “,3qu - 7o - Table 20. Chemical Composition of Carcass.Boneless Meat of Cattle of Similar Finish. (Results are expressed as percentage of carcass boneless meat wt.) Number Average of Days on Ether ggn;_ Calves Feed Extract Protein ‘Moisture Ash Steers, .. :““" ..... . ,1. . ,, Heifers, 1: Kill 1 9 121 27.2 15.9 55.6 0.8 ' Difference . Strs. over #9 1.7 0.1 -l.7 -0.l , Hefs. i Steers Kill 9 225 29.0' 15.9 53.9 0.7 Heifers, Kill 2 9 170 30.5 15.3 52.3 0.8 - Difference Strs. over 55 -0.5 0.6 1.6 -0.1 Hefs. Steers Kill fl 9 275 33.6 15.0 50.1 0.8 Heifers . Kill 3’ 9 225 3n.0 15.0 #9.8 0.7 Difference Strs. over 50 -0.# 0.0 0.3 0.1 Averages Steers 27 300% 15.6 5209 Dog Heifers 27 30. l5.# 52.6 0. ,- 71 4 . heifer carcasses contain a smaller proportion of shank than steer carcasses. The proportion of shank bone in the carcass decreased in cattle of both sexes as feeding progressed more so in steers. tthanin heifers. These results showed that the proportion of Shank bone in the carcasses of calves was dependent on both degree of finish and sex. Carcass Chemical Composition In order to make a basic comparison of cattle used in these experiments, chemical analyses were carried out on a uniform sample from the right half of each carcass. These analyses were carried out at the United States Department of Agriculture Research Station at Beltsville, Maryland. Fatness in beef cattle is a measure of finish. The three methods used to measure fatness in beef cattle are, namely: sensory (sight and feel), physical (separation of visible fat from other body components) and chemical (ether extract determination). The reliability of these methods increases in the order named. The chemical method is the most accurate because it measures fat that cannot be measured accurately by any other existing method. The percentage of ether extract in the edible portion, lean and fat, of the carcass followed a trend similar to that followed by the percentage of separable fat in the carcass. That is, the percentage of ether extract in the edible portion of the carcass was significantly higher in heifers than in T 1 1.. «.efl‘*hm .mnonpsm exp 90 sOHmmHeeoe up Aomme .boz .eonm .E4 mo .oom ;_mn. .meopowm pmoz use noHpodconm op oprmo sH annHm mo own on mo noprHom one 3032 He mic om wacqumnm .4 .0 mo H 0.3.3.. some swamp wees eHnMp mEp nH open one mom mm: mod. Ed me: «am New New emu Home. m m e.mm.._..o.mm .. am 3m 34 84 om: mom m3. mmm cum mmm S c eémuoém 2 J com mm: 84 Sum cam mm: mme mom mom 8m 3 2 Tamera S: be: $3 84.. oem Rm 9% mom. 13H m3 e m 98-0.8 em: . mod scm mi. m5 0 m $36.3 R: mp: $4 $4 RH mam one :8 mad 8;. a in overseas“ wanes» wanes» .mnH .mnH .mnH .mnH .mpH .mnH .on .0: .o: .0: pnooeoa A.mwom.1mnpw .mnom .mepm .mmemc.mapm_wmwom.mapm._‘.mwom .mnpm .memm.mapm g 58 mace 58 Hence Heats use mama 338 «see essences Hop nopmo ween non pooh .cz nH powepxo nH amneqo poz HenHm nonpov annHm mo seamen . .SmHnHm Ho mooawoe mnHmmonqu no oprwo pomfie: new , upseeenszmh hmnoeo as: new maHmm .mpstoz acom ammo mo popes: omenea4 rm“ oHnt semen «0 . .mnospso onp mo GOHmmHere an AmmmHv .Poz .ooem .Ed we .00m A M “Wong .mnopoom poo: new GOHposeoem 0p oproo :H :mHmHm mo oonwon mo aOHuoHom one oHoHpHH He no c.5555 .d .w no m oHnoe acne noxoo. one: oHnou. mHop 5” open one .mnHHnnoe eo pqnoeo ESEHGHEtm: was aneone manomoeeoe H .m: on H Scam mnHmson mosHo> wounH mo oHoom o GH cc .mmoqenHe gHeHe m: 38 genes mpsomoeeoe H .m: op H acne mnHmnoh monHoe. enough we oHoom o he a. .... mo . w.:: e.es :.o 0.: o.e o.e H«H.o Hi:.o m m m.mm-o.mm w.~ m.m m.w 0.0H m.m 0.5 H“H.o Him.m 0H m e.Hmoo.wm o.e :. .OH m.oa o.oa o.o . Hue.m Him.m HH Ha e.e~-o.:m o.mm o.mm .:H :.:H m.mH m.mH Him.m Hmw.: m m e.mmuo.om w.em o.oa .JH Hem.: o w o.e.-o.oa s.mH m.eH o.mm m.Hw o.om m.wa Hum.: H«H.: H : m.mauo.ma ...................... ”0.0g“ . . . . .xQUmHfl . . . . . . . . . . . . 002 002 unamopHmnH ...mecm...me»m..eecmA.meemw. ecm.eeem._..mecm .eeem .mecm.eeem caeemmaHmemimmmemyam :oPoHouaopuoqu.q0Hpaoe :oeo: 9H9 no sooH no on pace oHpHeo eH poonpwo menace ca eschews seeps manages: mmcseeae eo capem accuse cmMMae . mo oo on . .n3onm omHo one mpso neeuno>oHoaaopuquz no GOHpuoe oHnHuo qH Apooepwo nonpov you we momopaocnoe omonoad . nfim Mo moonmoc meHmoonoem no oHapoo noeHos ooo noopm no :oeo: pHn mo wsHHpHoe nmfi puma. 33.. Mo omega moan nH once. on. woos oHnHeo no mOHpon owoao>< mm oHnoe can ; 7h ; steers when cattle were slaughtered after 121 and 225 days of ifeeding. Also after 170 and 275 days of feeding the Percentage was higher than in steer carcasses, but the dif- ferences were not significant. The average percentage of ether ‘_euctract in the edible portion of the carcass was higher in lleifers than in steers in each kill of each trial. When cattle were matched by grades for finish, only small differences were found in the percentage of ether extract in the carcass due to sex. The results showed that the per- centage of ether extract in the edible portion of the carcass was largely dependent on degree of finish rather than sex. Correlation analyses showed that there was a close relationship between the percentage of ether extract in the edible portion of the carcass and the separable fat in.the carcass, see Table 7 of the Appendix. These results indicated that separable fat was a fairly accurate measure of fat in beef carcasses, even though it does not measure all of the fat in the carcass. The cattle used in these experiments were grouped according to the percentage of ether extract in the right side of the carcass by Branaman,.gt,al., (1936). Tables 21 and 22 correspond to Tables 1 and 3 in the publications cited and they show the relationship between the ether extract content of the right side of the carcass and certain production and meat factors. The authors used a different approach to analyze some of the factors involved. Moisture and protein are closely associated in biological systems. Therefore, any factor that causes one to vary should p a -75.. afifeect the other as well. These two constituents followed a trend opposite to that of ether extract. The percentages ' 01‘ moisture and protein in the edible portion of the carcass Were significantly higher in steers than in heifers when cattle were slaughtered after 121 and 225 days of feeding. then cattle were slaughtered after 170 and 275 days of feeding the percentages of’moisture and protein in the edible portion of the carcass were higher in steers than in heifers, although the.differenceS‘were too small to be significant at the levels used in testing differences. In cattle of similar finish there was practically no ‘ difference in the percentages of moisture and protein in the edible portion of the carcass. The results indicated that the percentages of moisture and protein in boneless meat were largely dependent on degree of finish rather than sex. The percentages of moisture and protein in the edible portion of the carcass decreased with increasing age and fatness. Neither sex nor length of feeding period had any sig- nificant effect on the percentage of ash in the edible portion of the carcasses. Results for the four measures of fatness used in these experiments are shown in Tables 23 and 21+, and Tables 1-19 of the Appendix, each increasing in reliability from left to right. Results in Table 23, comparing steers and heifers at each kill show that each measure was higher for heifers than i 76 - Table 23. Measures of Fatness (By Kills). Separable Ether Extract Days on Slaughter Carcass Fat (% of (% boneless §§£§l ,ggeed Spade Grade Carcass) meat) Stueers,' . .. 2‘“? iff. . , 32111 1 121 G G 18.3 21.2 HeiferS, . Kill 1 121 G J G / 22.8 27.2 'Difference ** ** Strs over -1/3 grade -1/3 grade -h.5 -6.0 Hefs. Steers, Kill 2 170 Ch - Ch - 2H.h 28.9 Heifers, * Kill 2 170 Ch Ch 27.0 30.5 Difference Strs over -l/3 grade -l/3 grade -2.6 -l.6 Hefs. Steers Kill 225 Ch Ch 26.1 29.0 Heifers, * Kill 3 225 P - P'- 30.2 34.0 Difference ** . ** Strs. over -2/3 grade -l/3 grade -h.l -5.0 Hefs. . Steers, Kill n 250 Ch / Ch / 30.6 33.6 Heifers, Kill u 250 P - Ch #- 32.0 3u.9 ~Difference Strs. over -l/3 grade 0 grade -l.h -l.3 Hefs. Average Steers 2h.9** 28.2 Heifers 28.0 31.7** * Significant at the 5 percent level. ** Significant at the 1 percent level. ‘ -‘77 - . Table 21F. Measures of Fatness (Cattle of Similar Finish). Separable Ether Extract Days on Slaughter Carcass Fat (% of (% boneless Se}: Feed Grade Grade gggrcass) meat) Steers, , . 4 .. . . . . "—5 Kill 2 170 Ch —. Ch - 24H 28.9 Heifers, Kill 1 121 G l G / 22.8 27.2 Difference Strs. over #9 1/3 grade 1/3 grade 1.6 1.7 Hefs. Steers Kill 3 225 Ch on 26.1 29.0 Heifers, _ K 11 170 Ch Ch 27.0 30.5 Difference Strs. over 55 0 grade 0 grade :0.9 -l.5 Hefs. . Steers Kill 11 275 Ch ,1 cn ,1 30.6 33.6 Heifers, Kill 3 225 P - P - 30.2 3k.0 Difference Strs. over 50 -1/3 grade -l/3 grade O.% -0.h Hefs. Averages Steers 27.0 30.2 Heifers 26.7 30. -78— for steers except for carcass grade in Kill ’+. The difference du£3 to sex was significant for slaughter grades only in Kill 3, carcass grades in Kills 1 and 2 and for separable fat and atller extract in Kills 1 and 3. There was a gradual increase in fatness measured 'by each method from Kill 1 to Kill 1+, except in slaughter and carcass grade for Kill # heifers. An attempt was made to space kills so that steers of the succeeding kill would be at a similar stage of fatness as that of the heifers in the previous kill. Results were tabulated in Table 2# to show how much success had been achieved. The results show one third grade difference in both slaughter cattle grades and carcass grades in favor of the steers when Kill 2 steers were compared with Kill 1 heifers. Both slaughter and carcass grades were equal for cattle of the two sexes when Kill 3 steers were compared with Kill 2 heifers. Howe ever, when Kill h steers were compared with Kill 3 heifers the heifers graded one third grade higher both as slaughter cattle and as carcass beef. 0n the basis of carcass separable fat and also ether extract, steers and heifers were closely matched when Kill h steers were compared with Kill 3 heifers. When Kill 2 steers were compared with Kill 1 heifers, steer carcasses contained slightly more separable fat and ether extract than those of heifers. When Kill 3 steers were matched with Kill 2 heifers, heifer carcasses contained slightly more separable fat and also more ether extract. Correlation coefficients for some of these factors are shown in Table 7 of the appendix with very high correlation. ‘ «La-{4‘51" c.» - 79 - SUMMARY AND CONCLUSIONS The effects of length of feeding period and sex on the Performance and carcass characteristics of steer and heifer czilves were studied in three experiments. Edual numbers of Eateers and heifers were individually full-fed a ration con- sisting of corn, cottonseed meal, corn silage and mixed alfalfa hay. Cattle were slaughtered at four different stages of finish ranging from Good to Low Prime, on the basis of _ grades previous to 1950, in an attempt to match the two sexes for fatness and grade. The average feeding periods for the h kills were 121, 170, 225 and 275 days. Slaughter grades were used to determine the time for slaughter, and these grades were used, together with dressing percentages, carcass grades, separable carcass fat and ether extract content of the right half carcass, to check the accuracy of matching the cattle for finish. Each of these comparisons showed that heifers were very similar in finish to steers that were fed approximately 50 days longer. On the average, steers were heavier than heifers at the beginning of each experiment and showed an increased weight advantage at the time of slaughter. The faster daily gains made by steers, except in Kill 1, accounted for the increased -weight advantage. The average initial weight for all steers was 384 pounds, and for all heifers it was 367 pounds. The average slaughter weight for steers in Kill h was 892, and for heifers 816 pounds. _ 80 - Cattle of both sexes maintained high and similar rates of gain early in the feeding period. The trend of heifer gains dropped after the first 8% days of feeding, while the steers maintained a high rate of gain for 1%0 days. The rate of gain of heifers dropped faster than those of steers, so that for nine steers and nine heifers in Kill h, slaughtered r- at 275 days, the difference in rate of gain was one-fourth 1 pound per day in favor of the steers. ‘With increasing body weights and decreasing rates of }.4 gain the daily gain made for each hundred pounds of body weight dropped more rapidly than the rate of gain. During the first 112 days of feeding daily TDN consumption for cattle of both sexes increased very rapidly and showed ‘very small differences due to sex. There was almost a 50 percent increase in daily TDN consumed by all cattle from the 28th to the 112th day. ‘After 112 days the daily TDN consumption of steers was almost level, while that of heifers dropped as feeding progressed. h Total digestible nutrients consumed per hundred pounds of body weight varied but little in amount for the first 112 days, however, after this period a consistent decrease was observed. There was not a consistent difference between the sexes. . Heifers required more TDN per pound of gain than steers, except in Kill 1, when cattle were compared by kills, with ‘the difference due to sex reaching a maximum of O.% pound for «cattle of Kill h. From Kill 1 to Kill # there was an increase f .I‘ ’w m _zrv" vi .. 81 ...‘ for steers of 0.8 pound of'TDN per pound of gain and 1.2:pounds of TDN for heifers. 'When cattle of similar finish.were_com- pared at slaughter time, there were very small differences that were not significant, and with steers requiring slightly more feed. Another comparison was made using a predicting equation- derived according to Fisher's Statistical Methods fer Research ‘Wbrkers and the results obtained by using this equation showed that nutrient requirement for gain was more affected by in- creasing fatness than by increased body weight. Shrink from feedlot to slaughter was not consistent for either sex or group of cattle. The percentage digestive content at slaughter was slightly higher in steers than in heifers which reduced the weight advantage of the steers ‘when_empty body weight was considered. There was a slight indication that the percentage of digestive content decreased with increasing fatness. The results showed that fat deposii- tion on the digestive tract of cattle, caul and ruffle fat, was dependent on degree of finish rather than sex. Differences between the sexes were small and not consistent, steers in-. creased 50 percent and heifers #0 percent in killing fat from Kill 1 to Kill h. It is of interest to note that on the average all steers were 10.5, 8.8 and 8.3 percent heavier than heifers in slaughter I weights, empty body weights and carcass weights respectively, which indicated that the percentage of offal was higher in steers than in heifers. ..82... ‘When cattle were compared by kills dressing percentages of heifers, based on slaughter and cold carcass weights,were higher than those of steers in each kill, with significant differences of l.# and 1.7 percent higher in Kills 2 and 3, respectively. When cattle were compared on the basis of similar finish, the dressing percentages of 27 steers and 27 tm‘ heifers averaged the same. t The percentage of hindquarter decreased 0.5 percent in 9 steer carcasses with increasing finish from the first to the fourth kill, while the percentage remained fairly constant for heifer carcasses. Heifer carcasses contained a larger proportion of hindquarter than steer carcasses in each kill, with significant differences of 1.0 and 1.2 percent more in Kills 3 and h, respectively. ‘Matching the cattle on the basis of finish did not affect the differences materially. 0n the basis of these results it was concluded that, on the average, the percentage of hindquarter is higher in heifer carcasses than in those of steers, and the reverse is true of the forequarter. ‘With increasing finish there were significant increases in the percentages of flank and rib cut, and a slight but not consistent increase in the percentage of kidney knob based on averages of all cattle slaughtered; while the percentages of round and shank decreased significantly. The percentages of chuck, loin, rump and plate were almost constant in each kill. ‘When cattle were compared by kills steer carcasses con- tained significantly higher percentages of chuck and shank, while heifer carcasses contained significantly higher per- a 83 _ centages of loin, flank and rib cut, and slightly higher percentages, but not significant, of kidney knob and plate. Sex had no appreciable effect on the percentage of rump in the carcass. ‘When cattle were matched for similar finish steer carcasses contained significantly higher percentages of chuck and shank, while heifer carcasses contained a signi- ficantly higher percentage of flank, otherwise there were no 3 significant differences in wholesale cuts._ j On the basis of these results it was concluded that only the percentages of hindquarter, forequarter, flank, chuck and shank were influenced by sex, while percentages of round, loin, kidney knob and rib out were largely influenced by degree of finish. The percentages of rump and plate in g the carcass were not significantly affected by either degree of finish or sex. The separable fat content of heifer carcasses was higher than that of steers at each kill when cattle were compared by kills. Differences of %.5 and %.l for Kills 1 and 3, res- pectively, were highly significant. However, when cattle were matched according to finish, steer carcasses averaged 27 per- cent in separable fat and heifers 26.7 percent. Steer car- casses were slightly higher in separable lean than those of heifers in each kill, with the difference of 2.9 for Kill 1 being significant at the 5 percent level.‘ The results for cattle of similar finish showed heifers to be slightly higher in separable lean than steers. The percentage of bone was significantly higher in steer carcasses both when cattle were -814... compared by kills and matched for finish. The results in- dicated that, except for bone, the physical composition of cattle carcasses was largely influenced by degree of finish, and in the case of bone, it was influenced by both finish and sex. _ The average increase in the proportion of meat to bone _ in the carcass increased approximately 25 percent, in the two sexes of cattle from Kill 1 through Kill R, a highly signifi- cant difference. ‘When cattle were compared by kills the meat to bone ratio was larger for heifer carcasses, with differ; ences for Kills 2 and 3 being significant at the 1 percent level and those of Kills-1 and % being significant at the 5 percent level. The differences for cattle matched for finish were smaller, but whenKill 3 steers were compared with Kill 2 heifers the difference of 0.7 percent, in favor of the heifers, was significant at the 5 percent level. The meat to bone ratio was influenced by degree of finish and sex; The percentage of fat,as percent of the carcass, in each wholesale cut increased significantly with increasing finish, except in the shank. There were significant decreases in.the percentage lean in all wholesale cuts from Kill 1 through Kill M, except in the round, rump and flank. Significant decreases occured for bone, except in the rump and rib cut. When cattle of the two sexes were compared by kills the only significant variation in separable lean in wholesale cuts as percentage of the carcass was more lean in steer chucks. The percentages of loin fat, rump fat, rib fat and flank fat were significantly higher in heifer carcasses. The percentages m. lei-.3! ..l‘ . l...‘ IIIJFHI I‘ll"! '- ~ «T..- . . -. :.'- o O i. . , . ‘ .4 '.*‘ ’ .7 as}! j, i V. b I is; " -H-__ .. _ -85.. of round bone, loin bone, chuck bone and shank bone were significantly higher in steer carcasses. There were no significant differences in percentages of fat, lean and bone in wholesale cuts when cattle were matched for finish, except that heifer carcasses contained a significantly higher per- centage of flank fat, and steer carcasses contained signi- ficantly higher percentages of chuck bone and shank bone. ’ The boneless meat of heifer carcasses contained a higher percentage of ether extract than steers in each kill when cattle were compared by kills, with highly significant dif- ferences due to sex being 6.0 and 5.0 percent for Kills 1 and 3, respectively. In cattle of similar finish the ether exe tract content was slightly higher in the boneless meat of heifer carcasses but not significant. The percentages of protein and moisture in carcass bone- less meat were higher in steers in each kill and significantly higher in Kills 2 and 3. In cattle of similar finish these percentages were still higher for steer although not signi- ficant. According to these results, sex has no significant influence on the chemical composition of carcass boneless meat in yearling cattle of similar grade. The four measures of fatness used in these experiments, namely: slaughter grade, carcass grade, separable carcass fat and ether extract content of carcass boneless meat, showed steers and heifers to be very closely matched for finish when steers were fed approximately 50 days_longer than heifers. —* _ ’Zt‘rw .—_fi Table 1. STEERS - 86 _ APPENDIX Measures of Fatness, Kill 1 Steers and Heifers Ether Extract Calf Days Feeder Slaughter Carcass Dressing Separable (% of No. on Grade Grade Grade Feed Trial 1’ 1% 126 - M X G .. 1 16 126 Ch K G % G K 1 18 126 F - G G - 1 Trial 2 16 105’ Ch - G - G - 2% 105 Ch I G M l 2 105' F — Ch - Ch Trial 3 16 132 Ch / G G 17 132 Ch Ch Ch 39 132 Ch Ch - G - Average 9 Steers 12i Ch / G G HEIFERS Trial 1 h 126 G x G - M I 6 126 Ch Ch - Ch — 13 126 G G 2’ Ch - Trial 2 5 105' F — Ch - Ch 9 105 Ch G / Ch - 11 105 Ch G G Trial 3 ’+ 132 F - Ch Ch 6 132 Ch Ch - Ch 11 132 Ch - G G Average 9 Heifers 176 Ch - G x* G x * Significant at 5 percent level ‘*Significant at 1 percent level mmw e o WQH percent Fat (% of Boneless Carcass} Meat) 17.0 21.0 1 2 nu» oust; O O 0 much: 2821 25.0 WOOL-J swac: O OKDJ? 27.2** Table 2. Measures of Fatness, Kill 2 Steers and Heifers STEERS Calf Days Feeder Slaughter Carcass Dressing Separable (% of No. on Grade Grade Grade Feed Trial 1 21 175 Ch Ch Ch 59.2 21.4 22 175 Ch - Ch - Ch - 53.5 17.5 2 175 Ch - G G / 5 . 17.5 Trial 2 17 15% Ch - G / Ch - 60.3 28. 26 15% F Ch Ch 60.1 27.9 27 15h G / G / Ch - 58.1 29. Trial 3 1% 182 F - Ch / Ch % 61.6 27.6 ii 182 Ch .4 G / G . 56.7 2MB 2 182 Ch Ch Ch - 60.1 2%. Average, 9 Steers - 170 Ch Ch - Ch - 59.# 2#.4 HEIFERS Trial 1 8 175' Ch Ch Ch - 61.0 21. 10 175 G /' G Ch 60.6 19.3 11 175 Ch Ch - Ch / 60.2 23.1 Trial 2 1 151+ Ch .1 Ch ,1 Ch / 61. 29.0 12 15% Ch Ch - Ch 60. 31.3 Trial 3 1' 182 F - Ch ¥ Ch % 60.9 31.6 5 182 F - Ch I Ch / 60.2 28.7 Average 9 Heifers 175 Ch Ch* Ch 60.8* 27.0 * Significant at 5 percent level .. 87 .. APPENDIX percent Fat (% of Boneless Cargagsl Meat) Ether Extract romeo Demo 0 O 0 row www MOI-4 O O OCDCh _ 88 - APPENDIX Table 3. Measures of Fatness, Kill 3 Steers and Heifers STEERS Ether Extract Calf Days Feeder Slaughter Carcass Dressing Separable (% of No. on Grade Grade Grade percent Fat (% of Boneless Feed Carcass) Meat) Trial 1 ' year 17 22% Ch P - P - 59.h 30.5 3 .0 1 22. 22%. Ch Ch - Ch - 58.h 21.1 .0 27 .22H Ch G I G I 59.H 20.9 2h.0 . Trial 2 f 1 11 ‘~ 18 203 Ch / Ch - G ,1 58g 23.9 26.7 ’e' 25 203 Ch { Ch P - 63.2 32.2 35.1 Trial 3 13 2%? F - Ch Ch / 61.% 30.1 32. 20 2h7 Ch Ch / P'- 6h.4 31. 3#. Average, 9 Steers 225 Ch ; Ch Ch 60.h 26.1 29.0 HEIFERS Trial 1 3 22% Ch - Ch P - -60.5 28.2 30.8 7 22% G I Ch / P - 60.6 29.3 33.6 Trial 2 a. 203 F P P 63.h 32.3 37.6 203 Ch - Ch P - 63.1 31.7 36.0 15 203 Ch - Ch 7 Ch J 62.6 3h.1 38.3 Trial 3 0 2M7 Ch - Ch - Ch - 61.9 25.3 27.7 3 2%? G Ch / Ch 62.9 31.0 3h.3 9 2%? Ch 7 P P - 6h.0 3h.2 38.1 Avera e 9 Heifers 32% Ch - P - P —* 62.1** 30.2** 3h.0 I"Significant at 5 percent level I”Significant at 1 percent level. Table h. l 89 - APPENDIX Measures of Fatness, Kill h Steers and Heifers STEERS Ether Extract Calf Days Feeder Slaughter Carcass Dressing Separable (% of No. on Grade Grade Grade percent Fat (% of Boneless ____E_§29£_ Carcagg) Meat) Trial 1 fines 19 273 Ch Ch P - 60.8 30.0 3a.7 } 20 273 Ch 2‘ P " P "' 6305 3008 3 e2 2% 273 G I G I Ch - 59.3 21.2 25. } I 22 259 Ch "' P " P " 6’+09 3701 3906 — 29 259 Ch P - P‘- 61.3 30.7 33.h Trial 3 0 29% Ch Ch / Ch 63.2 31.2 3H.3 19 29% Ch - Ch Ch / 61.# 29.5 32.2 21 29% Ch. P - Ch 63.1 29.9 32. A er 9 9 Steers v 357% on - on x on 7 62.3 30.6 33.6 HEIFERS Trial 1 l 273 Ch - P - P - 62.7 33.6 36.0 2 273 Ch - Ch - Ch - 60.7 2 .8 29.1 Trial 2 6 259 Ch ,1 P P - 62.9 31+.5 36. 10 259 Ch - P - P - 65.3 33.7 36.# 13 259 Ch - P P — 63. 35.3 38. Trial 3 2 291+ Ch - Ch :6 Ch 61.2 30.1» 32. 8 29% Ch / Ch Ch 63.7 2 .3 32. Avera e 9 Heifers 375 Ch - Ch %' P - 62.8 32.0 3h.9 - 90 - APPENDIX Table 5. Feed Consumed Per Hundred Pounds Gain Days ‘ Alfalfa Steer on Ground Cottonseed Corn mixed Beet Cane N0, Feed Corn Meal 3§ilage Hay Pulp M01asses Trial 1 '7' ‘° ' ‘l ‘ 13 126 This steer's record incomplete. 16 126 313.6 60.7 2 3.2 100.3 18 126 537.6 80.0 5.7 113.2 tax. :1 153 133-3 221,-; 1,,1 O O 2 O 0 ' 2 175 332.3 63.2 2Eg.3 107.3 f 17 223 02.5 70.0 210.5 1 8.5 7_ 22 223 .1 61.0 196.7 110.6 a; 1 27 223 365.6 63.2 183.3 103.0 E 19 273 539.8 71.5 181.5 113.6 20 273 570.1 71.5 189.3 13 .3 23 273 553:0 73. 177.3 111.0 Trial 16 105 300.8 50.1 175.5 102.6 2% 105 383.1 65.7 229.9 133.8 2 105 3.1 67.3 235.7 137.5 1 153 312.5 68.8 230.7 139.5 26 153 ‘350.1 75.0 262.6 152.1 27 153 302.3 67.1 233.7 135.7 18 203 78.0 6 .0 200.0 1 .3 23 203 10.3 68.3 219.9 133.1 25 203 312.1 68.7 219.7 133.7 19 259 289.9 65.0 210.0 1 6.1 22 259 3 7.0 76.2 235.7 159.6 29 259 0.5 80.1 256.7 168.3 Trial 16 132 337.1 57.5 202. 120.7 17 132 311.6 51.6 181. 108.1 39 132 390.3 63.8 227.6 133.0 13 182 363.9 60.6 212.7 125.1 1a 182 389.1 63.7 226.9 132.6 2 182 352.3 58.5 205.3 120.6 1 337 326.9 g8.g 1 3'0 1h8°6 13°C 20 237 33728 7223 2052 15333 1227 0 293 36 '8 68'8 180. %%§.6 30.%3.3 O O O 0 2 O 20 g 33:1. g. 73.1 % $02 1 .g 230 302- - 91 _ APPENDIX Table 6. Feed Consumed Per Hundred Pounds Gain Days Alfalfa Heifer on Ground Cottonseed Corn mixed Beet Cane N0. Feed Cgrn 'Meal Silage Hay, Pulp Molasses 1 .2 .1 209. 1 . 126 338.9 5 .7 259.1 36.0 13 126 312.6 61.3 255.3 131. rd... 10 1 31 .2 g3.0 2 .3 . ' 11 133 .13... 6... .33. 33.3 ,- 3 323 517.3 72.3 216.8 133.1 5 . . 2 . . . 3 23.33.. 33.. 133.7 1 3. I 4 1 27 g 7.2 5.7 121.6 122.1 ' 2 . 1. 1 . 1 8. 9 333 523.7 71.3 1.3 1 .3 Trial 2 5 105' 332.3. 58.7 205.6 120.0 11 105 373.0 62.3 218.2 127. 1 153. 92.3 6 .3 228.3 132.7 7 153. 13.3 6g.9 231.1 133.6 12 153 339.3 73.2 256.2 1 .7 203 3 .9 75.3 230.3 15 .1 a 203 .5 73.5 235.3 152.8 15 203 315. 69.3 217.0 137.6 6 259 317.5 69.6 225.1 135.8 10 259 3 0.8 71.8 2 2.1 150.2 13 259 2.0 77.0 2 .2 161. Trial 3 3 132 33 .7 57.0 200.3 118.9 6 132 3g’.0 59.7 208.9 123.3 11 132 3 8.0 57.7 202.8 120.9 1 182 318.3 69.5 233.0 132.8 5 182 366.3 60.9 213.6 123.g 12 182 28.2 71.1 239.6 136. 0 237 353.9 73.9 210.3 157.7 16.6 3 237 332.7 71.5 201.8 150.3 13.6 9 237 309.3 67.8 203.3 132.3 11.3 2 293 336.3 75.0 166.8 136.0 30.3 3.3 7 293 00.1 83.6 206.2 167.0 27.7 3.0 8 293 99.5 8 .0 206.0 163.3 30.6 3.2 - 92 - HHO. m mo.o pom mmwoamo mapmpmomm _ - Spas mafia Hana 63 pan oapmnmamm wHo. m ow.o I owmnm mmmonmo mmo. \ :u.o \ ommpqmoumm msfimmmnn I Spas poms wmoamaon mo pcopqoo powapxm nonpm 00. N mm.o \ poms mmoaonon mo pampnoo pomnpxm gonna mo. \ 53.0 \ ommpcooaom mqflmmonm . I npw3.pmm manmhmmmm ONO. 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