May, 1939] Peotein Requirements of Chickens 19 



Summary 



As the percentage protein content of ration increased from 15 to 19 per 

 cent, a definite increase in body weight of chicks fed these rations also 

 occurred. These results are in harmony with previous work at this 

 station indicating that protein levels of from 18 to 20 per cent during the 

 first 12-week period produce the greatest gains in weight. 



There is no apparent relationship between per cent protein fed and 

 total feed consumption, but a very definite relationship occurs between 

 total feed consumed and body weight attained throughout the experi- 

 mental period. 



Those groups receiving the protein mixture and fish meal supplements 

 were significantly heavier in weight at 12 weeks of age than were the meat 

 scrap or dried skimmilk fed groups. 



Generally, the groups receiving the lower protein percentages were the 

 most efficient in feed utilization during the growing period; i.e., 12-23 

 weeks of age. 



Those groups receiving fish meal as the sole source of animal protein 

 concentrate averaged (1) a heavier rate of production and produced a 

 greater number of eggs per bird than did the other groups (2) were 

 lowest in feed cost per dozen eggs produced, and (3) earliest in sexual 

 maturity as measured by average days to first egg. 



There appears to be no significant relationship between per cent 

 protein fed and size of egg laid. 



Percentage protein in ration did not significantly influence age at first 



egg- 

 No significant relationship was observed between mortality and source 



of animal protein fed. 



Under the conditions of this experiment the maximum amount of 

 protein which can be supplied from either meat scraps or dried skimmilk 

 is quite definitely lower than that which is furnished by vacuum processed 

 fish meal. 



Odor and flavor tests on eggs produced by and carcasses of birds fed the 

 fish meal ration containing 19 per cent protein content (13 per cent of 

 fish meal) showed quite definitely that no outstanding distasteful odor or 

 flavor could be detected in either the meat or eggs. 



Bibliography and Selected References 



1 Ackerson, C. W.; Blish, M. J. and Mussehl, F. E. "The Utilization of Food 

 Elements by Growing Chicks" Nebraska Exp. St. Res. Bull. 94, 1937. 



2 Almquist, H. L.; Stokstad, E. L. and Holbrook, E. R. "Supplementary Values 

 of Animal Protein Concentrates in Chick Rations" Jour, of Nutrition, Vol. 10, 

 No. 2, 1935. 



3 Asmundson, V. S.; Jukes, T. H.; Fyler, H. M. and Maxwell, M. L. "The Effect 

 of Certain Fish Meals and Fish Oils in the Ration on the Flavor of the Turkey" 

 Poul. Sci., Vol. 17, No. 2, 1938. 



4 and Biely, J. "Fish Meal Supplements for Chicks" I. Sci. Agr. 13: 236-248. 



5 Bauernfeind, J. C. "Calcium and Phosphorus Requirements of Poultry" Abst. 

 from Cornell Nutr. School, Oct., 1937. 



6 Carver, J. S.; St. John, J. L. ; Aspinwall, T. E. and Flor, I. H. "The Protein 

 Requirements of Chickens" Poul. Sci., Vol. 11, No. 45, 1932. 



7 Carver, J. S.; St. John, J. L. ; Miller, M. W. and Bearse, G. E. "The Com- 

 parative Efficiency of Various Proteins for Growing Chicks" Wash. Bull. 321, 

 1935. 



