Effects of Chick Age on Meal Utilization

Researchers at the University of Illinois investigated the effects of the physical and morphological development of the chick’s digestive tract on the utilization of either a crystalline amino acid or corn-soybean meal diet. Six replicates of eight male chicks were fed: 1) a corn-soybean meal diet from 0-21 days of age; 2) a cornstarch-crystalline amino acid diet for 0 to 21 days of age; or 3) a corn-soybean meal diet for 0-7 days of age and then switched to the crystalline amino acid diet for the remaining 14 days. Results indicated that the crystalline amino acid diet significantly reduced weight gains during either the 14 or 21-day feeding period. Feeding crystalline amino acids reduced weight of the small intestine, pancreas, liver, gizzard and proventriculus compared to the chicks fed the corn-soybean diet. Further study indicated the crystalline amino acid diets depressed intestinal villi height and crypt depth. The researchers concluded that the reduced growth of chicks fed a crystalline amino acid diet was due in part to the slower growth and development of the gastrointestinal tract.

Batal, A.B. and C.M. Parsons. 2002. Effects of age on development of digestive organs and performance of chicks fed a corn-soybean meal versus a crystalline amino acid diet. Poultry Sci. 81(9):1338-1341.