OVERDUE FINES: 25¢ per dcy per item RETURNING LIBRARY MATERIALS. Place in book return to rem charge from circulation rec: MANAGEMENT AND NUTRITIONAL TECHNIQUES TO INCREASE EGG PRODUCTION by Abdullah Ali Alsobayel A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Poultry Science 1980 ABSTRACT MANAGEMENT AND NUTRITIONAL TECHNIQUES TO INCREASE EGG PRODUCTION by Abdullah Ali Alsobayel Four experiments were conducted to test a combination of several dietary treatments to determine which factors might be utilized to in- crease egg production of one of the major egg laying strains used by Michigan commercial poultrymen. In the first experiment a series of four dietary treatments using methionine and protein standards used in British egg production rations, were compared under the prevailing Michigan con- ditions. All of the four diets are isocaloric and contain varying levels of methionine and protein. In the second experiment a typical egg laying hen ration used in Michigan was compared with another diet which con- tained an equal amount of protein and methionine and had a similar ration composition. The two rations were different in their metabolizable energy content. This was to compare the caloric differences found in British rations and Michigan egg laying hen rations. The third experi- ment was to compare the ration composition differences found in British rations and Michigan egg laying hen rations. The fourth experiment was Abdullah Ali Alsobayel to compare different cage densities. Two birds and three birds per cage were compared. The trial utilized twenty-two week old Dekalb 23l Pullets and consisted of seven experimental treatments with four replicates in each. Each experimental group was composed of eight birds maintained in 20 Cm. x 40 Cm. cage, two birds per cage, except that in experimental group "H" each group was composed of twelve birds, confined three birds per 20 Cm. x 40 Cm. cage. The experiment was performed in order to investigate the effect of the different experimental diets and cage densities upon egg production, feed intake, feed conversion, daily protein and metaboliz- able energy intake, body weight gain, egg weight and egg quality, number of lost eggs and mortality. At the end of the experimental period, data obtained were subjected to statistical analysis. From the studies reported herein, neither the high protein and methionine levels used in certain European standard diets nor the high metabolizable energy level used in one of U.S. egg laying rations would explain the differences in egg production performance found between Michigan and European commercial laying hens. However, when the diet had a high metabolizable energy content or a high protein level, the birds tended to consume more feed and gained more weight. It had also been shown that the different ration composition used in the experiment did not influence the rate of egg production or exterior and interior Abdullah Ali Alsobayel egg quality. Under the conditions of the experiment, a 16.94 percent protein and 0.36 percent methionine levels and 2838 Kcal of metabolizable energy per Kg. of diet were sufficient to support highest rate of egg production and best feed conversion. 0n the other hand, two birds per cage had a better rate of lay and lower body weight gain than three birds confined in the same size. To the People of My Country and my Parents ii ACKNOWLEDGEMENTS Dr. J. C. Flegal has been an excellent and very c00perative major professor. I am very thankful for his help and moral support. Also Dr. C. C. Sheppard should be thanked for his suggestions and guidance. Dr. T. H. Coleman, whose suggestions were most useful and whose associations will be a pleasant experience of my stay at Michigan State University. Dr. P. T. Magee deserves a lot of credit for his invaluable and patient statistical help and constructive review of this manu- script. Dr. H. C. Zindel, Chairman of Department of Poultry Science, for his well-intended advice. Michigan State University, Poultry Science Department, for making this work possible. I also want to thank my friends and graduate students, who offered me a lot of help and encouragement. iii TABLE OF CONTENTS Page LIST OF TABLES ......................... v APPENDIX A & B LIST OF TABLES ................. vi INTRODUCTION .......................... 1 REVIEW OF LITERATURE ...................... 4 Energy Level of Poultry Rations ............... 4 Protein Level of Poultry Rations ............... 9 Methionine Levels in Poultry Laying Rations ......... 16 The Influence of Cage Density on Egg Production ....... 19 MATERIALS AND METHODS ..................... 24 RESULTS ............................ 34 DISCUSSION ......................... I. . 37 SUMMARY AND CONCLUSION ..................... 42 APPENDIXES Appendix A .......................... 45 Appendix B .......................... 75 BIBLIOGRAPHY .......................... 87 iv Table LIST OF TABLES THE EFFECT OF VARIOUS DIETARY TREATMENTS ON EGG PRODUCTION, FEED INTAKE, FEED CONVERSION AND DAILY PROTEIN AND ENERGY INTAKE OF THE EXPERIMENTAL GROUPS A, B, C, AND D ................. THE EFFECT OF VARIOUS DIETARY TREATMENTS 0N BODY WEIGHT, EGG WEIGHT, HAUGH UNIT SCORES, SHELL THICK- NESS. NUMBER OF LOST EGGS AND MORTALITY OF THE EXPERIMENTAL GROUPS A, B, C, AND D ........... THE EFFECT OF VARIOUS DIETARY TREATMENTS ON EGG PRODUCTION, FEED INTAKE, FEED CONVERSION, DAILY PROTEIN AND ENERGY INTAKE, BODY HEIGHT GAIN, EGG HEIGHT, HAUGH UNIT SCORES, SHELL THICKNESS, NUMBER OF LOST EGGS AND MORTALITY OF THE EXPERIMENTAL GROUPS F AND G ..................... THE EFFECT OF VARIOUS DIETARY TREATMENT ON EGG PRODUCTION, FEED INTAKE, FEED CONVERSION, DAILY PROTEIN AND ENERGY INTAKE, BODY WEIGHT GAIN, EGG WEIGHT, HAUGH UNIT SCORES, SHELL THICKNESS, NUMBER OF LOST EGGS AND MORTALITY OF THE EXPERIMENTAL GROUPS D AND G ..................... THE EFFECT OF TWO DIFFERENT CAGES DENSITIES 0N EGG PRODUCTION, FEED INTAKE, FEED CONVERSION, DAILY PROTEIN AND ENERGY INTAKE, BODY WEIGHT GAIN, HAUGH UNIT SCORES, SHELL THICKNESS, NUMBER OF LOST EGGS AND MORTALITY OF EXPERIMENTAL GROUPS F AND H ...... Page 29 3O 31 32 33 Table APPENDIX A AND B LIST OF TABLES Appendix A 1. ANALYSIS OF VARIANCE OF FINAL AVERAGE HEN-HOUSED EGG PRODUCTION OF THE EXPERIMENTAL GROUPS A, B, C, AND D .......................... MEANS DIFFERENCES OF FINAL AVERAGE HEN-HOUSED EGG PRODUCTION OF THE EXPERIMENTAL GROUPS A, B, C, AND D .......................... ANALYSIS OF VARIANCE OF FINAL AVERAGE HEN-DAY EGG PRODUCTION OF THE EXPERIMENTAL GROUPS A, B, C, AND D .......................... MEANS DIFFERENCES OF FINAL AVERAGE HEN-HOUSED EGG PRODUCTION OF THE EXPERIMENTAL GROUPS A, B, C, AND D .......................... ANALYSIS OF VARIANCE OF FINAL AVERAGE FEED INTAKE OF THE EXPERIMENTAL GROUPS A, B, C, AND D ......... MEANS DIFFERENCES OF FINAL AVERAGE FEED INTAKE OF THE EXPERIMENTAL GROUPS A, B, C, AND D ......... ANALYSIS OF VARIANCE OF FINAL AVERAGE FEED CONVERSION OF THE EXPERIMENTAL GROUPS A, B, C, AND D ........ MEANS DIFFERENCES OF FINAL AVERAGE FEED CONVERSION OF THE EXPERIMENTAL GROUPS A, B, C, AND D ........ ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY PROTEIN INTAKE OF THE EXPERIMENTAL GROUPS A, B, C, AND D vi Page 45 45 46 46 47 47 49 APPENDIX A AND B LIST OF TABLES (cont'd.) Table Appendix A (cont'd.) 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. MEANS DIFFERENCES OF FINAL AVERAGE DAILY PROTEIN INTAKE OF THE EXPERIMENTAL GROUPS A, B, C, AND D . . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY ENERGY INTAKE OF THE EXPERIMENTAL GROUPS A, B, C, AND D ........................ MEANS DIFFERENCES OF FINAL AVERAGE DAILY ENERGY INTAKE OF THE EXPERIMENTAL GROUPS A, B, C, AND D . . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE BODY WEIGHT GAIN OF THE EXPERIMENTAL GROUPS A, B, C, AND D . . . . MEANS DIFFERENCES OF FINAL AVERAGE BODY WEIGHT GAIN OF THE EXPERIMENTAL GROUPS A, B, C, AND D . . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE EGG WEIGHT OF THE DIFFERENT EXPERIMENTAL GROUPS A, B. C, AND D ........................ MEANS DIFFERENCES OF FINAL AVERAGE EGG HEIGHT OF THE EXPERIMENTAL GROUPS A, B, C, AND D ........ ANALYSIS OF VARIANCE OF FINAL AVERAGE HAUGH UNIT SCORES OF EXPERIMENTAL GROUPS A, B, C, AND D ..... MEANS DIFFERENCES OF FINAL AVERAGE HAUGH UNIT SCORES OF THE EXPERIMENTAL GROUPS A, B, C, AND D . . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE SHELL THICKNESS OF THE EXPERIMENTAL GROUPS A, B, C, AND D MEANS DIFFERENCES OF FINAL AVERAGE SHELL THICKNESS OF THE EXPERIMENTAL GROUPS A, B, C, AND D ...... ANALYSIS OF VARIANCE OF FINAL AVERAGE NUMBER OF LOST EGGS OF THE EXPERIMENTAL GROUPS A, B, C, AND D vii Page 49 50 5O 51 51 52 52 53 53 54 54 55 APPENDIX A AND B LIST OF TABLES (cont'd.) Table Appendix A (cont'd.) 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. MEANS DIFFERENCES OF FINAL AVERAGE NUMBER OF LOST EGGS OF THE EXPERIMENTAL GROUPS A, B, C, AND D . . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE MORTALITY OF THE EXPERIMENTAL GROUPS A, B, C, AND D ...... MEANS DIFFERENCES OF FINAL AVERAGE MORTALITY OF THE EXPERIMENTAL GROUPS A, B, C, AND D ........ ANALYSIS OF VARIANCE OF FINAL AVERAGE HEN-HOUSED EGG PRODUCTION OF THE EXPERIMENTAL GROUPS F AND G. . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE HEN-DAY EGG PRODUCTION OF THE EXPERIMENTAL GROUPS F AND G . . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE FEED INTAKE OF THE EXPERIMENTAL GROUPS F AND G .......... ANALYSIS OF VARIANCE OF FINAL AVERAGE FEED CONVER- SION OF THE EXPERIMENTAL GROUPS F AND G ....... ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY PROTEIN INTAKE OF THE EXPERIMENTAL GROUPS F AND G ...... ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY ENERGY INTAKE OF THE EXPERIMENTAL GROUPS F AND G ...... ANALYSIS OF VARIANCE OF FINAL AVERAGE BODY WEIGHT GAIN OF THE EXPERIMENTAL GROUPS F AND G ....... ANALYSIS OF VARIANCE OF FINAL AVERAGE EGG WEIGHT OF THE EXPERIMENTAL GROUPS F AND G ......... ANALYSIS OF VARIANCE OF FINAL AVERAGE HAUGH UNIT SCORES OF THE EXPERIMENTAL GROUPS F AND G ...... ANALYSIS OF VARIANCE OF FINAL AVERAGE SHELL THICK- NESS OF THE EXPERIMENTAL GROUPS F AND G ....... viii Page 55 56 56 57 57 58 58 59 59 60 6O 61 61 APPENDIX A AND B LIST OF TABLES (cont'd.) Table Page Appendix A (cont'd.) 35. ANALYSIS OF VARIANCE OF FINAL AVERAGE NUMBER OF EGG LOST OF THE EXPERIMENTAL GROUPS OF F AND G ..... 62 36. ANALYSIS OF VARIANCE OF FINAL AVERAGE MORTALITY OF THE EXPERIMENTAL GROUPS F AND G ........... 62 37. ANALYSIS OF VARIANCE OF HEN-HOUSED EGG PRODUCTION OF THE EXPERIMENTAL GROUPS D AND G ........... 63 38. ANALYSIS OF VARIANCE OF FINAL AVERAGE HEN-DAY EGG PRODUCTION OF THE EXPERIMENTAL GROUPS D AND G ..... 63 39. ANALYSIS OF FINAL AVERAGE FEED INTAKE OF THE EXPERIMENTAL GROUPS D AND G .............. 64 40. ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY PROTEIN INTAKE OF THE EXPERIMENTAL GROUPS D AND G ....... 64 41. ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY ENERGY INTAKE OF THE EXPERIMENTAL GROUPS D AND G ....... 65 42. ANALYSIS OF VARIANCE OF FINAL AVERAGE FEED CONVER- SION OF THE EXPERIMENTAL GROUPS D,AND G ........ 65 43. ANALYSIS OF VARIANCE OF FINAL AVERAGE BODY WEIGHT GAIN OF THE EXPERIMENTAL GROUPS D AND G ........ 66 44. ANALYSIS OF VARIANCE OF FINAL AVERAGE EGG WEIGHT OF THE EXPERIMENTAL GROUP D AND G ........... 66 45. ANALYSIS OF VARIANCE OF HAUGH UNIT SCORES OF THE EXPERIMENTAL GROUPS D AND G .............. 67 46. ANALYSIS OF VARIANCE OF FINAL AVERAGE SHELL THICK- NESS OF THE EXPERIMENTAL GROUPS D AND G ........ 67 47. ANALYSIS OF VARIANCE OF FINAL AVERAGE NUMBER OF LOST EGGS OF THE EXPERIMENTAL GROUPS D AND G ........ 68 ix APPENDIX A AND 8 LIST OF TABLES (cont'd.) Table Appendix A (cont'd.) 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. ANALYSIS OF VARIANCE OF FINAL AVERAGE MORTALITY OF THE EXPERIMENTAL GROUPS D AND G .......... ANALYSIS OF VARIANCE OF FINAL AVERAGE HEN-HOUSED EGG PRODUCTION OF THE EXPERIMENTAL GROUPS F AND H ANALYSIS OF VARIANCE OF FINAL AVERAGE HEN-DAY EGG PRODUCTION OF THE EXPERIMENTAL GROUPS F AND H . . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE FEED INTAKE OF THE EXPERIMENTAL GROUPS F AND H ......... ANALYSIS OF VARIANCE OF FINAL AVERAGE FEED CON- VERSION OF THE EXPERIMENTAL GROUPS F AND H ...... ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY PROTEIN INTAKE OF THE EXPERIMENTAL GROUPS F AND H ...... ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY ENERGY INTAKE OF THE EXPERIMENTAL GROUPS F AND H ...... ANALYSIS OF VARIANCE OF FINAL AVERAGE DAILY BODY WEIGHT GAIN OF THE EXPERIMENTAL GROUPS F AND H . . . . ANALYSIS OF VARIANCE OF FINAL AVERAGE EGG HEIGHT OF THE EXPERIMENTAL GROUPS F AND H .......... ANALYSIS OF VARIANCE OF FINAL AVERAGE HAUGH UNIT SCORES OF THE EXPERIMENTAL GROUPS F AND H ...... ANALYSIS OF VARIANCE OF FINAL AVERAGE SHELL THICK- NESS OF THE EXPERIMENTAL GROUPS F AND H ....... ANALYSIS OF VARIANCE OF FINAL AVERAGE NUMBER OF EGGS LOST OF THE EXPERIMENTAL GROUPS F AND H ..... ANALYSIS OF VARIANCE OF FINAL AVERAGE MORTALITY OF THE EXPERIMENTAL GROUP F AND H .......... Page 68 69 69 70 70 71 71 72 72 73 73 74 74 APPENDIX A AND B LIST OF TABLES (cont'd.) Table Appendix B l. COMPOSITION OF THE BRITISH STANDARD DIET "A" USED IN THE EXPERIMENT ................... 2. NUTRIENT COMPOSITION OF THE BRITISH STANDARD DIET "A" USED IN THE EXPERIMENT BASED ON CALCULATED ANALYSIS ....................... 3. COMPOSITION OF THE BRITISH STANDARD DIET "B" USED IN THE EXPERIMENT ................... 4. NUTRIENT COMPOSITION OF THE BRITISH STANDARD DIET "B" USED IN THE EXPERIMENT BASED ON CALCULATED ANALYSIS ....................... 5. COMPOSITION OF THE BRITISH STANDARD DIET "C" USED IN THE EXPERIMENT ................... 6. NUTRIENT COMPOSITION OF THE BRITISH STANDARD DIET "C" USED IN THE EXPERIMENT BASED ON CALCULATED ANALYSIS ....................... 7. COMPOSITION OF THE BRITISH STANDARD DIET "D" USED IN THE EXPERIMENT ........ . .......... 8. NUTRIENT COMPOSITION OF THE BRITISH STANDARD DIET "D“ USED IN THE EXPERIMENT BASED ON CALCULATED ANALYSIS ....................... 9. COMPOSITION OF THE TYPICAL EGG LAYING HEN RATION USED IN MICHIGAN "E" USED IN THE EXPERIMENT ...... 10. NUTRIENT COMPOSITION OF THE TYPICAL EGG LAYING RATION USED IN MICHIGAN "E" USED IN THE EXPERIMENT BASED ON CALCULATED ANALYSIS ............. ll. COMPOSITION OF THE DIET "G" USED IN THE EXPERIMENT 12. NUTRIENT COMPOSITION OF THE DIET "G“ USED IN THE EXPERIMENT BASED ON CALCULATED ANALYSIS ........ xi Page 75 76 77 78 79 80 81 82 83 84 85 INTRODUCTION In all the modern breeds and strains of egg production chickens, there has been marked increase in egg production during the last 75 years. The conditions which have been responsible for this have been the following: a) selection and breeding, b) supplying nutritious feed, c) comfortable housing, d) improved management, and e) preventive disease control. In 1937, there began a steady and almost continuous increase in egg production, which by 1969 had added 100 eggs to the average, to bring the total to 220 eggs per layer during a normal production cycle [U.S. Department of Agriculture, 1969]. On the other hand, continued selection and breeding for high rate of lay, together with improved feed- ing, housing and management have made it possible fbr large commercial egg farms in the U.S. and EurOpe to count on annual yields of 240 to 250 eggs per hen. It has been realized for some time that the egg production achieved by U.S. producers is much less than the genetic potential. It has been suggested that many European producers are more nearly achiev- ing the maximum genetically attainable egg numbers during a normal pro- duction cycle. In a letter dated November 22, 1976 which had been sent to Dr. C. C. Sheppard by the U.K. Ministry of Agriculture, Fisheries and Food, it was mentioned that many U.K. egg producers were getting 280 eggs in 52 weeks. It has also been reported that U.S. egg producers were getting only 240 eggs during the same production cycle [Flegal, 1977]. Speculations as to the possible reasons for increased production in the U.K. are as follows: 1) The simple corn/soya diet used in the U.S. may not pro- vide the same nutritional standard as the more complex ones used in more European poultry diets. 2) Animal protein, fish meal, and meat meal make up a sub- stantial portion of most European poultry rations. 3) Methionine levels used are higher in European poultry rations. 4) U.S. poultry rations contain more energy per pound of ration than their European counterparts. 5) U.S. rearing diets may be high in their energy content due to the use of corn, whereas European rearing diets contain a large preportion of barley. 6) Stocking densities per cage are much higher in the U.S. 7) Others: small flocks, different climate, different strains, etc. If any of these aforementioned factors can be shown to improve egg production of U.S. birds when compared to typical conditions used in the U.S., more efficiency in the poultry industry could be expected. The purpose of the studies reported herein was to test several dietary factors used by European commercial poultrymen and various cage densities to determine which factors might be utilized to increase egg production of one of the major egg laying strains used by MiChigan commercial poultrymen. The factors tested were: a) methionine level, b) protein level, c) energy level, d) ration composition, and e) cage densities. These studies were conducted May 27, 1977 through May 27, l978 at the Michigan State University Poultry Science Department Research and Teaching Center. REVIEW OF LITERATURE It has been known for a long time that the energy and protein, content of the diet, the rate of feeding, the environmental temperature and the characteristics of the animal itself all affect the performance of the animal. Energy Level of Poultry Rations Most investigators have agreed that there is a direct relation- ship between the energy content of the diet and daily intake. Hill [1962] pointed out that chickens tend to eat less as the energy content of the diet is increased. Morris [1958] reported that the dietary energy level has influence on the voluntary caloric intake of laying birds, Dewar and Gleaves [1969] have shown that the level of energy and protein in a given diet influence feed intake. Guenthner et al. [1972] reported that increasing the level of dietary energy from 2,500 to 3,300 calories of metabloizable energy per kg of diet significantly decreased feed con- sumption and improved feed conversion. Lillie et al. [1976] demonstrated an inverse relationship of dietary metabolizable energy level and feed intake at 29.5, 21.5 and 13.0 Centigrade. In respect to egg production, it appears there is a controversy among many investigators as to whether it is increased, decreased, or not changed when the energy content of the diet is increased. Heuser and co-workers [1945] were among the first to show that rations low in fiber content supported a higher rate of egg production than similar rations high in fiber content. Bird and Hhitson [1946] studied layer rations of high and low fiber content with respect to productive efficiency and showed that efficiency was related con- versely to fiber content. Quisenberry et al. [1949] present evidence that increased egg production and improved feed efficiency could be ob- tained through the use of high energy diets. Skinner et a1. [1951] found that higher egg production, greater feed efficiency and larger eggs were obtained on a higher efficiency ration than on a conventional breeder mash. Lillie et al. [1952] observed that a marked increase in efficiency of egg production resulted from incorporation of lard in the laying hens' diet. Singsen et al. [1952] reported that hens fed a high corn diet (61.25%) required as much as 13% less feed per dozen eggs, were slightly heavier in body weight, and tended to have a higher rate of egg produc- tion than hens fed a corn-oat-middling ration. Hill et al. [1956] re- ported that the rate of egg production was increased as the dietary energy level was increased during the months of cold weather. Hill [1956] reported that feeding hens a constant protein level of 17.5% of the diet showed that the relationship between energy level and relative efficiency was linear within the range of 740 to 1030 calories of pro— ductive energy per pound of diet. Harms et a1. [1957] obtained a signi- ficant improvement in egg production, in addition to feed efficiency and body weight gains with White Rocks, White Leghorns, and New Hampshires, when hens were fed a high energy ration compared to a low energy ration. Peterson et al. [1960] reported that egg production of hens fed a low energy ration was not equal to that obtained from hens fed a high energy ration; on the other hand, he observed that feed consumption was signif- icantly increased, while egg weight and albumin quality were not influ- enced by the high energy ration. Sykes [1972] indicated that egg weight began to fall before egg production was affected and that body weight was also affected following energy restriction. Reid et a1. [1977] reported that limiting metabolizable energy intake in laying hen diets reduced both egg weight and hen-day production. Donaldson [1962] indicated that egg production was reduced when a balanced ration which contained 30.4 percent of added fat was fed to leghorn pullets. Goodling et a1. [1968] found that increasing the level of dietary energy resulted in lower egg production. Santana and Quisenberry [1968] reported that a high energy level made for larger body weight, lower egg production, higher feed efficiency, but larger egg size except when the protein was 12% or lower. Gleaves et a1 [1968] reported, as estimated dietary energy was increased, there was a concurrent decrease in body weight gain, egg production and egg weight. Grover et a1. [1972] reported that a high energy treatment depressed egg production, increased body weight gain and decreased total feed consumption. Quisenberry et al. [1967] showed that phasing both the protein and energy levels was superior to phasing either alone. Peterson [1971] reported that daily metabolizable energy intake can be reduced to 240 KCal per bird per day without affecting egg output, providing that the daily intake of other nutrients was adequate. Peterson et al. [1973] showed that the mature hen derives more metaboliz- able energy from several feed ingredients than does a growing chick, in- dicating that the calculated energy values for laying hen diets may be considerably lower than actually realized in feeding. He also concluded that the constancy of metabolizable energy values makes them a poor cri- terion for the evaluation of nutrient balance, housing and management. Gerry [1954] noted that neither egg production nor egg size was improved by feeding high efficiency rations as compared with conventional rations. Mueller [1956] found that hens fed a barly-oat ration equaled the pro- duction of the birds fed a corn ration. Anderson et a1. [1957] obtained increased feed efficiency but not egg production when a ration that con- tained 884 calories of productive energy per pound was compared to one with 723 PE calories. MacIntyre and Aiken [1957] compared rations that contained 710 and 840 calories productive energy per pound in one experi- ment and 840 and 900 calories productive energy per pound in another. Rate of egg production was not influenced by energy level although feed intake and feed efficiency were markedly affected. Berg et al. [1956] found that the rate of lay of leghorns in floor pens was not affected at several levels of metabolizable energy varying from 1100 to_l367 calories productive energy per pound in diets of either 15 or 17 percent protein content. Treat et a1. [1960] reported the caloric level of the diet apparently did not affect egg production, since hens that received the basal diet laid at a rate comparable to any of the diets with added fat. 0n the other hand, he observed an improvement in feed efficiency when fat was added to the basal diet. Gordon et al. [1962] indicated that energy content of the diet had no direct effect on egg production or egg weight; however, he found that increasing the energy content of the diet decreased feed intake, thereby improving the feed efficiency. Hochreich et a1. [1958] added 6.6 percent stablized yellow grease to a 950 calorie productive energy ration without effect on egg production. Heywang and Vavich [1962] reported no significant change in egg production as dietary levels increased in the diet. They also found that feed intake decreased progressively as the calorie content of the diets increased. March and Biely [1963] reported that an increased dietary energy level reduced egg weight. Egg production was not affected by high energy level. Bragg and Hodgson [1969] reported no difference in egg production as the di- etary energy level was increased. Jones et al. [1976] evaluated the feeding of 2.67, 2.85 and 2.99 KCal metabolizable energy per gram diets at temperatures of 4.5, 21 and 45 centigrade and found that the level of dietary energy had no significant effect on egg production. Hill et al. [1954 a,b] reported a marked decreaSe in the amount of feed required per dozen eggs produced when the caloric denSity of the diet was increased from 746 to 930 calories of productive energy per pound. McDaniel et al. [1957] observed a 12.2 percent increase in feed efficiency, as measured by feed required per dozen eggs produced, with the addition of 88 calo- ries of productive energy per pound to a layer ration that contained 17 percent protein. Price et al. [1957] found that feed required per dozen of eggs was reduced by increasing the energy content of the diet. Speers and Balloun [1967] reported that feed conversion was improved by increas- ing dietary energy of the diet only when protein intake was adequate. Harms et a1. [1962] presented evidence to indicate that hens will over- consume on either protein or energy in an attempt to meet their need for the other nutrient. Protein Level of Poultry_Rations From a review of the literature, it seems there is controversy among many investigators about the protein level needed in the diet to maintain maximum egg production. A wide range was published which runs from 11 to 21 percent. Heuser et al. [1945] indicated that a 15 percent protein content in the laying hen diet was sufficient to support maximum egg production. The National Research Council [1950] recommended that 10 diets containing 15 percent protein were sufficient to support adequate ,egg production. Heywang et a1. [1955] indicated that pullets may re- quire a protein level of 15 percent in the diet during heat stress. Thornton et al. [1957] reported that 11 percent protein in the diet was adequate for maximum_egg production. Berg and Bearse [1957] stated that a 14 percent protein level in a diet that contained 1015 Kcal of productive energy per pound depressedegg production, whereas the same protein level supported better egg production than higher protein levels on a diet that contained 700 Kcal of productive energy per pound. Miller et al. [1957] indicated that they obtained good egg production with diets that contained 12.5 and 13.5 percent protein. Thornton and Whittet [1959] found that a 13 percent protein level in the diet was com- parable with higher levels of protein for egg production and feed effi- ciency. Frank and Waibel [1960] presented data showing that 15 and 14.9 percent protein levels in the diet were sufficient to support egg pro- duction. Bray and Gesel [1961] stated that a minimum of 13 to 14 grams of protein a day for a leghorn pullet was adequate for egg production. They also observed that whenever daily protein intake of hens fell below 12 grams, a decreased rate of production occurred, either simultaneously or during the following period. Owings [1964] noted that reducing the protein content of the diet from 17.5 percent to 15.3 or 13.3 had no detrimental effects on egg production, body weight gain, egg size or Haugh Unit scores. He also indicated that feed required to produce a ll dozen eggs was significantly less on the lower protein levels. Shapiro and Fisher [1965] found that a minimum of 13 to 14 grams daily protein intake supported egg production up to a level of 76 percent. Lillie and Denton [1965] stated that a minimum of 15 grams of protein per leghorn per day appeared to be adequate for egg production, body weight and egg size. Smith [1967] found no difference in egg production when ratif- were fed which contained protein levels of ll, 15 and 19 percent. Lillie and Denton [1967] compared dietary protein levels of 12, 14 and 16 per- cent. They found that when the 12 percent protein level was fed, egg pro- duction was significantly lower than that obtained with 14 percent protein level, but was equivalent to that obtained with 16 percent proten level. Blaylock et a1. [1967] concluded that no more than 14 grams of protein intake per hen per day were required to support egg production up to a level of 80 percent. Shapiro [1968] reported that 13 to 14 grams of pro- tein per hen per day would support 70 percent egg production and satis- factory nitrogen retention of 800 mg per day. Novacek and Carlson [1969] stated that the protein requirement of layer hens was not more than 11.3 grams per day for a 4.4 pound hen at a level of 60 percent egg production. Manoukes and Young [1969] reported that a total intake of 14.4 to 15 . grams of protein per hen per day supported Optimum egg production. Reid and Weber [1974] found that the feeding of a 14 percent protein diet that contained 0.55 percent total sulfur amino acids supported maximum egg production. Thayer et a1. [1974] have evaluated the protein requirement 12 of hybrid pullets to be 14 to 15 grams per hen per day. Reid [1976] found a 14.5 percent dietary protein was adequate to support an egg pro- duction rate of 77 percent at an average intake of 16.64 grams per hen per day. Hamilton [1978] reported that productive performance and egg quality of S.C.W.L. hens were not affected when the level of dietary protein was decreased from 17 to 13 percent at 325 days of age or when the birds received a 15 percent protein diet from 143 to 504 days of age. Reid et al. [1951] observed that 18 percent protein in feed was superior to 13 or 15 percent protein in feed when the feed was formulated to con- tain a relatively high level of energy. Milton and Ingram [1957] found that an 18 percent protein level was superior to a 14 or 16 percent pro tein level. Hochreich et a1. [1958] reported that a level of 17 percent protein in the feed was required to maintain maximum egg production and feed efficiency, when the diet contained at least 950 Kcal productive energy per pound. Quisenberry and Bradley [1962] found that egg pro- duction (on a hen-day basis), egg weight and efficiency of feed utiliza- tion were significantly improved as dietary protein level was increased from 13 to 17 percent. Touchburn and Naber [1962] stated that a mini- mum of 17 grams protein intake was required per pullet per day to support 72% egg production. Gordon et al. [1962] indicated that increasing the protein level to 19 percent resulted in improved egg production, egg weight and feed efficiency with no improvement observed from 23 percent protein level. On the other hand, at low energy level, 860 calories of l3 productive energy per pound, 23 percent protein level depressed egg weight, while at high calorie level, 1100 calories of productive energy per pound, it did not. Harms and Waldroup [1963] found that feeding a 11.6 percent protein level significantly reduced the length of the laying cycle, which resulted in a significantly lower rate of egg production compared to birds receiving a 14.3 or 17 percent protein level. Biely and March [1964] reported that hens which received a dietary level of 16 percent protein consistently laid larger eggs than did those which re- ceived a dietary level of 14 percent protein. Britzman and Carlson [1965] concluded that a layer ration with a protein content of 11 percen+ would support egg production for a period of 5 or 6 months, but at a level ten percent below that obtained from hens fed a 16 percent protein. Bray et a1. [1965] observed that egg weight increased with an increase in dietary protein level above 14 percent, at a dietary level of 1450 Kcal of metabolizable energy per pound, but was depressed when the 14 percent dietary protein level was fed in combination with a dietary energy level of 1100 carlories productive energy per pound of diet. Tonkinson et a1. [1968] set a protein intake requirement of 17.5 grams of protein per hen per day with a daily energy intake of 343 Kcal per hen. Santana and Quisenberry [1968] indicated that a diet that con- tained 16 percent protein was satisfactory for body weight gain and resulted in the highest egg production. They also found that feed cost was lower per dozen eggs produced and mortality appeared not to be l4 affected. Gleaves et a1. [1968] reported that as estimated dietary pro- tein level was increased from 13 to 19 percent in the diet, there was ' an increase in observed body weight gain, egg production and egg weight. Nivas and Sunde [1969] provided layer hens with protein intakes of 14, 16, and 18 grams per hen per day. They observed that egg production was lower when protein intake was 14 to 16 grams per hen per day compared to an intake of 18 to 20 grams per hen per day. They also noted an in- crease in body weight gain and egg weight as protein intake was above 1‘ grams per day per hen. [Aiken et al. [1973] evaluated the protein intake and protein source on performance of seven strains of laying hens. Their findings suggested that 17 grams of protein intake per hen per day was adequate for egg production and no significant strain differences in protein need were noted. Deaton and Quisenberry [1965] reported that egg production of laying hens that received 17 or 14 percent protein in their diet was not significantly different. 0n the other hand, the hens that received 17 percent protein in their diet laid significantly heavier eggs, had significantly better feed efficiency and significantly lower Haugh Unit scores, but no difference in shell thickness. Combs [1962] noted that for a given diet, a decrease in intake would result in a de- crease in protein intake per day and performance would fall. Coligado and Quisenberry [1961] found that a gradual decrease in dietary protein level had little or no effect on egg production. Guenthner et al. [1972] vaported that a gradual increase of protein level—-from 13.9 to 18.3 -15 percent of the diet--did not influence feed intake and feed conversion; although the rate of egg production tended to increase, it was not sig- nificantly altered by increase in protein levels. Sharpe et alI [1965] found that decreasing the dietary protein level from 16 to 12 percent at 343 days of age caused a decrease in both feed and protein intake. Reid et al. [1965] assumed that protein requirement will decline with age be- cause of declining egg output, although it has been recognized that seasonal differences in rate of lay and feed consumption may also affect dietary protein requirement. Campbell [1966] concluded that a 13 per- cent protein diet, while failing to support a maximum peak of production, was equal to 15 or 17 percent protein diets after egg production had declined to a rate of 70 percent. Fisher and Morris [1967] reported that reducing the dietary protein level from 16 to 12 percent and 14.7 and 10.7 percent, respectively at 219 days or 343 days of age caused a decrease in egg production. Jennings et a1. [1972] indicated that when comparisons of egg production were made at a given protein intake, the older birds consistently produced some 10 to 13 grams less egg material than the young ones, so more protein was required for older birds for a given level of production. In respect to egg quality, most investiga- tors have agreed that ration composition has no effect on egg quality. Card and Sloan [1935] reported that feeding a high proportion of the common grains, corn, wheat or oats, did not affect interior egg quality. Griminger and Scott [1954] found that the different grains could not be 16 shown to influence egg weight, shell thickness or.the standing-up qual- ity of the egg. Orr et al. [1958] reported that the addition of 2.5 and 5.0 percent fat had no effect on egg quality or egg weight. Mueller [1956] indicated that egg weight was affected significantly by the ration composition but not shell thickness nor water loss of eggs during storage. 0n the other hand, eggs of hens that received a barley-oats- meat scrap diet had significantly higher Haugh Unit scores, compared to the others. Harms and Douglas [1960] observed that dietary changes which resulted in an improved rate of egg production caused the interior egg quality to decrease. Methionine Levels in PoultrygLaying Rations There is also controversy among investigators about the level of methionine required to support adequate egg production. Titus [1955] indicated that methionine was the first limiting amino acid in a corn- soybean meal diet. Heywang [1956] reported that, when a soybean type diet that contained .28 percent methionine and .56 percent cystine was supplemented with .085 percent DL methionine, the methionine supplementa- tion had no appreciable consistent effect on egg production. Johnson and Fisher [1959] observed that a diet that contained 10.4 percent pro- tein plus. .09 percent added methionine and lysine supported egg pro- duction equal to that obtained with a diet that contained 15.7 percent 17 protein. Harms et al. [1962] obtained a significantly improved perfor- mance when diets were supplemented with .075 percent methionine (MHA) in the diet, when the protein level in the diet was 14.7 or 15.7 but not when the protein level was 16.7 percent. Quisenberry [1965] presented evidence showing methionine supplementation consistently improved protein conversion in low protein laying hen rations. Fernandez et al. [1973] reported that a diet that contained 13 percent protein supplemented with .05 percent lysine and .05 percent methionine was as effective as diets with 15, 17 or 18 percent protein for supporting egg production and egg size. Damron and Harms [1973] noted that diets supplemented with a .528 percent sulfur amino acid level significantly improved egg production, egg weight and feed conversion. Reid and Weber [1974] found that the feeding of a 14 percent protein diet that contained .55 percent total Sulfur amino acids supported maximum egg production. Mehring et a1. [1954] found that the addition of .0847 percent methionine to a corn- soybean diet had no statistically significant effect on egg production. The quantity of feed required per dozen eggs or per unit gain in live weight was reduced. The basal diet was estimated to contain about .25 to .31 percent methionine and .26 percent cystine. Bradly and Quisenberry [1961] reported a slight non-significant decrease in egg production of birds fed 16 percent and 18 percent protein diets when these diets were supplemented with lysine and/or methionine. Amino acid supplementation caused increased egg production of hens fed a 14 percent protein diet. 18 Stangeland and Carlson [1961] observed that supplementation of .15 per— cent of the diet with methionine alone to a corn-soybean diet containing 11 percent protein did not affect egg production, whereas the combination of methionine and lysine consistently improved_egg production and feed efficiency. Egg production and feed efficiency were superior on the posi- tive control diet that contained 16 percent protein. Britzman and Carlson [1965] demonstrated that, when methionine did not show a re- sponse, either in egg numbers, egg weight or feed conversion, the protein intake was generally in excess of 16 grams per hen per day. Muller and Balloun [1974] have reported that addition of methionine to a low-protein, corn-soybean meal diet, fed to light weight laying hens may not always increase production performance. Leong and McGinnis [1952] indicated that the level of methionine required for supporting maximum egg produc- tion, body weight gain and egg size appeared to be approximately .28 per- cent in the presence of .25 percent cystine. Ingram and Little [1958] reported that when using a wheat-peanut meal basal diet supplemented with various levels of DL-methionine, the requirement for this amino acid was determined to be .25 percent of the ration. Levels of methionine as low as .225 percent supported egg production; however, egg size and body weight were not maintained, and as amino acid imbalance raised the re- quirement to .325 percent of the diet. The National Research Council [1960] sets a methionine requirement of either .53 percent of the diet or .28 percent of the diet in the presence of .25 percent of dietary 19 . cystine, for a diet.containing 1300 Kcal per pound. Combs [1964] indi- cated that the methionine requirement per henper day was aboUt 295 mg. Bray [1965] estimated the requirement to be 233 mg. per hen per day. Fisher and Morris [1970] estimated the requirement to be 275 mg. per bird per day for maximum egg yield of pullets during the early stage of lay. The National Research Council [1971] recommends a level of .26 percent methionine and .25 percent cystine in a ration containing 2850 Kcal metabolizable energy per kg. Ingram et al. [1951] concluded that methi- onine requirement of laying hens was not more than .38 percent of the diet in the presence of .25 percent of the dietary cystine. Combs [ indicated that a 2 kg. hen producing 40 grams of egg per day would re- quire 302 mg. methionine per day. Carlson and Guenthner [1969] noted that the methionine requirement for laying hens was in excess of 300 mg. per hen per day for the first four months of production, but between 289 and 328 mg. per hen per day during the later stage of lay. The Influence of Cage Density on Egg Production Hartman [1953] indicated that poor air circulation, lack of space for holding the wings away from the body and other factors may increase hot weather hazard for hens. Craig [1969] found a relationship between crowding, aggressiveness and age at sexual maturity. Champion and 20 Zindel [1968], using 1, 2 and 3 birds in 20.3 cm. x 40.6 cm. cages, 4 birds in 40.6 cm. and 40.6 cm. cages, and 5 birds in 40.6 cm. x 40.6 cm. cages, indicated that egg production declined and mortality increased as the bird density increased; however, they concluded that income per unit of cage space can be maximized by caging layers in multiple cage units in preference to caging layers individually. They argued that whether the commercial egg producer could hold cage birds at a partic- ular density may be dependent in part upon his ability to control cannibalism. Wilson et al. [1967] reported that egg production was significantly less with three birds per cage than with one or two birds per cage. They also noted strain interactions with respect to the effect of bird densities on egg production and egg weight and that egg quality characteristics were affected little by treatment and that major differences were due to strain effects. 0n the other hand, in- creasing cage density resulted in smaller body weight and increased mortality. Coligado and Quisenberry [1967] observed that crowding the birds depressed egg production and increased mortality, especially in large cages. No specific effects on body weight and egg size were noted. They also reported that feed efficiency was slightly favored by higher density. Tower et a1. [1967] indicated that 10 birds per cage group produced the highest number of eggs per bird, had larger sized eggs, had the best feed conversion and had the lowest mortality compared to 2,5 or 20 birds per cage. Doran et a1. [1967] 21 reported that birds housed individually in 25.4 cm. x 45.0 cm. cages matured two to six days earlier, produced three to eleven more eggs, had a five percent higher survival, required less feed per dozen eggs and were 31.8 grams higher in body weight than two birds housed per cage. Marr et a1. [1967] reported that, when given equal floor space, two birds per 25.4 cm. x 40.6 cm. cage produced at a higher rate than did three, four, five or six birds per cage. Owings et al. [1967] stated there was no significant difference in egg production, feed efficiency, or morta- lity of birds confined two birds per cage or three birds per cage. Magruder and Nelson [1966] observed that two birds housed in a 20.3 cm. x 40.6 cm. cage had better egg production and three percent better liv- ability than when a single layer was housed in the same cage. They also mentioned that there was little influence of density or cage construction regarding interior quality of eggs as measured by Haugh Units and that eggs showed less incidence of heavy staining as density decreased. Bell and Little [1966] reported a significant decrease in egg production an an increase in mortality with increased cage densities. Elmslie et al. [1966] indicated that egg production declined and mortality increased as bird population or bird densities increased. He also reported that a hysterical and featherless condition developed among birds housed 12 to 14 per 41 cm. x 123 cm. cage, but not among birds housed three per 41 cm. x 141 cm. cage. Bramhell et al. [1966] reported that higher population densities per cage generally decreased the number of eggs and increased 22 mortality. Cook and Dembnicki [1966] observed that pullets housed one bird per 25I4 cm. x 45.7 cm. cage were significantly better in egg pro- duction than pullets housed in double or colony cages, i.e., two birds in a 25.4 cm. x 45.7 cm. cage, and five birds in a 45.7 cm. x 50.8 cm. cage. Blount [1965] suggested that two birds per cage were always better than one because of their companionship, their supplementary heat in colder weather and stimulus which each may give to the other's appetite. M0: at al. [1965] reported that cage density had a highly significant effect on hen-housed egg production and feed efficiency but no effect on mortal- ity. Two females per cage showed the least cost to produce a dozen eggs. Lowe and Heywang [1964] reported that higher mortality and greater body weight gain in the multiple cage adversely affected egg production. Shupe and Quisenberry [1961] reported that egg production declined and mortality increased if the bird population or density increased. They also observed a significant difference in egg production and mortality between individually caged birds and colony birds; in favor of the in- dividually caged birds. Marr and Green [1970] stated that space per bird was more of an influence on egg production than the number of birds per cage. They also observed that there were no significant differences in ,egg production among social densities of two, three, four, five, six, or seven hens with comparable space per bird. Adams and Jackson [1970] failed to observe a significant difference in performance or shell Qaulity of six strains of White Leghorn type chickens housed at different 23 densities. They also observed that crowding reduces rate of lay. Birds housed at a high density level had higher Haugh Unit scores. Ruszler and Quisenberry [1970] reported that space per bird was more of an in- fluence on egg production than was number of birds per cage. Mather and Gleaves [1970] stated that egg production was significantly influenced by both density and stocks. The egg production decreased as the number of birds per cage was increased. They also observed that there was no stock-density interaction and that there were more bare backs in the cages with six birds density. Grover et a1, [1972] reported that greater bird density depressed egg production, increased mortality and depressed body weight gains; however, under the conditions of their study, in- creasing density from two to three birds per cage failed to significantly depress egg production. It has been reported by many investigators that energy content of the diet influences the daily feed intake. In reSpect to egg pro- duction, there is a controversy among many investigators as to whether it is increased, decreased or not changed when the metabolizable energy content of the diet is increased. On the other hand, most of the re- searchers have reported higher body weight gain and improvement in feed efficiency, when hens were fed a high energy ration compared to a low energy ration. MATERIALS AND METHODS Four experiments were conducted to test a combination of several dietary treatments to determine which factors might be utilized to in- crease egg production of one of the major egg laying strains used by Michigan commercial poultrymen. In the first experiment a series of four dietary treatments using methionine and protein standards used ir ' egg production ration [Appendix B, l, 3, 5, and 7] were compared under the prevailing Michigan conditions. All of the four British rations were isocaloric and calculated to contain 2822 calories M.E. per kg. of diet. The four standard diets which are designated with "A", "B", "C", and "0" contained 17.52, 17.27, 16.94, and 16.27 percent of protein, respectively, and 0.40%, 0.38%, 0.36%, and 0.34% of methionine respectively [Appendix B, 2, 4, 6, and 8]. In the second experiment, a typical egg laying hen ration used in Michigan which is designated with "E", was compared with another diet which is designated with “G" [Appendix B. 9 and 11]. The two rations contained an equal amount of protein and methionine, 16.54 percent of protein and 0.34 percent of methionine and had a similar ration composition. The two rations were different in their metabolizable energy content. Ration “E" contained 2958 Cal metabolizable energy per 24 25 _kg. of diet, whereas ration "Gt contained metabolizable energy approxi- mately equal to the British rations [Appendix B, 10 and.12]. This was to compare the calorie differences found in British and Michigan egg laying rations. The third experiment was to compare the British ration "D" with the ration “G". This was to compare the ration composition differences found in British rations and Michigan egg laying rations. The British ration "D" was chosen for this comparison, since it contai an equal amount of methionine and protein as ration "G". The fourth ex- periment was to compare different cage densities. Two birds and three birds per cage were compared. The two experimental groups received ration "E" [Appendix B, 9]. All of the diets were mixed at the Michigan State University poultry farm. The trial utilized twenty-two-week-old DeKalb 231 pullets. The trial consisted of seven experimental treatments. There were four replicates of each experimental group. Each experimental group was com- posed of eight birds, maintained in 20 cm. x 40 cm. cages, two birds per cage, except that in experimental treatment "H" each group was compose: of 12 birds, confined three birds per 20 cm. x 40 cm. cage. For the first three months of the experimental period, in the two experimental , groups which were used to compare cage densities, any birds which died, were replaced. All eXperimental groups received feed and water ad libitum and 13.5 hours of light daily for the first three months, the light was increased to 16 hours of light daily for the rest of the 26 experimental period. The different experimental groups and their repli- cates were randomly assigned to the cages in the environmentally con— trolled laying house. The different experimental groups were given the same designation as the different experimental diets except for the cage density experimental groups, which were designated with "F" and "H" and received diet "E". The different experimental groups were on test for one production cycle consisting of 365 days. The following data were collected: 1) Egg Production I .Egg production was recorded daily for each experimental group. At the end of the trial, the final average hen-housed and final average hen-day egg production [Table l, 3, 4, and 5] were calculated and ex- pressed in percent. 2) Feed Intake and Feed Conversion The amount of the total feed consumed was recorded and at the end of the experimental period, the final average feed intake [Table l, 3, 4, and 5] for each experimental group was obtained. Next, the final average feed conversion of the different experimental groups was cal- culated. The feed intake is expressed in kg. and the feed conversion is expressed in kg. of feed per dozen eggs produced. 27. 3) Daily Protein.and Metabolizable Energy Intake Based on calculated analysis,the final average daily protein and metabolizable energy intake of the different experimental groups were obtained [Table l, 3, 4, and 5]. The average daily protein intake is ex- pressed in gram/bird and the average daily M.E. intake is expressed in cal./bird. 4) Body Weight Gain The birds were weighed at the beginning and end of the trial. The final average body weight gain [Table 2, 3, 4, and 5] was obtained and expressed in grams. The body weight gain of the birds that died dur ing the trial were excluded. 5) Egg Weight and_Egg Quality The final average egg weight is expressed in grams [Table 2, 3, 4, and 5]. Albumen height was measured by Albumen Height Micrometer, then was converted to Haugh Units [Table 2, 3, 4, and 5] obtained from the Haugh Unit Chart made by the U.S. Department of Agriculture. Shell thic ness [Table 2, 3, 4, and 5] was measured by Shell Thickness Gauge and is expressed in mm. Shell thickness and_egg quality were measured three consecutive days of each month for the different experimental groups. 6) Number of Lost Eggs The term "lost eggs“ included soft shell eggs, eggs without shells, 28 misshapen eggs and broken eggs. They were recorded daily and the final average number of losteggs of each experimental group was determined [Table 2, 3, 4, and 5]. 7) Mortality The mortality was recorded daily and at the end of the trial, the final average mortality was obtained for each experimental group and expressed in percent [Table 2, 3, 4, and 5]. 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