The Effects of Feeding High Protein Diets to Chickens

DIETS for chickens containing more than 22% crude protein have been considered high protein diets in this study. Milne (1932) observed an adverse effect on the growth and liveability of chickens fed diets containing 38% protein. Heller and Penquite (1945) found poor growth in chickens on diets containing 35 or 40% protein. Almquist and Asmundson (1944), Heller and Penquite (1945), and Singsen (1949) obtained satisfactory growth of chickens fed diets up to 30% protein. Donaldson et al. (1956) found that less protein was required for a unit gain in weight of chicks as the calorie/protein ratio was increased for the diets containing 15 to 27% protein and 1760 and 2640 kcal./kg. of productive (P.E.) energy. Sunde (1956) overcame the growth-depressing effects in the diets containing 1440 and 1700 kcal./kg. P.E. due to an increase in the protein level from 20 to 28% by increasing the energy levels from 1760 to …