Effect of Trypsin Supplementation on the Utilization by the Chick of Diets Containing Raw Soybean Oil Meal

Abstract

Four experiments were conduced in an attempt to determine the effect of trypsin supplementation on the metabolizable energy of diets containing raw soybean oil meal for the chick. The results indicated that trypsin supplementation would not overcome the growth-depressing properties of raw soybean oil meal. Supplementing diets containing raw soybean oil meal with a crude or crystalline trypsin preparation did not improve the metabolizable energy of the nonfat components of these diets. A level of 2.4% of a crude trypsin 1:300 concentrate was markedly growth-depressing when added to a diet containing heated soybean oil meal. A level of 0.75% of crystalline trypsin was markedly growth-depressing when added to diets containing either raw or heated meal. The trypsin preparations were more detrimental in diets containing heated soybean oil meal than in diets containing raw soybean oil meal. The digestibility of soybean oil in the basal diet used in these studies was markedly depressed when raw soybean oil meal was included in the diet. Trypsin supplementation of the diets improved digestibility of the dietary soybean oil. The effect of raw soybeans on fat digestibility appeared to depend upon the age of the chick. Chicks fed diets containing raw soybean oil meal showed a marked hypertrophy of the pancreas compared with chicks receiving heated meal. Supplementing the diet with the crude trypsin preparation appeared to slightly reduce the pancreatic hypertrophy but crystalline trypsin was without effect.