Alkaline heating of canola and rapeseed meals reduces toxicity for chicks

A simple method for improving the nutritive quality of canola and high gluc osinolate rapeseed meals for monogastric animals (chicks) was developed; th e meals were mixed with NaHCO3 and NH4HCO3, then heated in a conventional o ven. Chicks fed untreated canola or rapeseed meals gained less weight than those fed a soybean meal diet, whereas chicks fed the alkaline-heated meals had weight gains not significantly different than those fed the soybean di et. The antithyroid effect of the untreated rapeseed meal was reduced by al kaline treatment of the meals, as shown by improved T4 and free T4 levels i n chicks fed the processed products. In chicks fed untreated or alkaline-tr eated canola or alkaline heated rapeseed meal, all thyroid hormone levels w ere similar to those of birds fed the soybean meal diet. However, heart tis sue of chicks fed diets containing rapeseed or canola meals showed muscle f iber degeneration, although relative heart weights were the same in all gro ups. Liver tissue from most of the chicks in all dietary groups appeared no rmal or only slightly abnormal. The nutritive value of both rapeseed and ca nola meals was improved by this simple processing technique.