Soy Flour in Milk Replacers for Young Calves

Abstract

Calves were fed milk replacers containing fully cooked soy flour as the only source of protein. Other ingredients were hydrogenated vegetable oil, lactose, methionine, nfinerals, vitamins, and an antibiotic. The results from four trials indicate that the nutritive value of soy flour for young calves can be improved markedly by exposing the flour to an acid enviromnent, pH 4.0 for five hours at 37 C, prior to its inclusion in the replacer. Calves fed acid-treated soy flour grew at nearly twice the rate of those receiving untreated soy flour. The nature of the alteration induced in soy flour by the acid treatment and the manner in which this change enhances the utilization of nutrients by the calf were not identified. In a fifth trial, calves fed replacers containing lightly cooked soy flour lost weight rapidly, though the loss was not quite so pronounced when the soy flour was exposed to the acid treatment.