Effect of substitution of soybean meal with treated or untreated high glucosinolate mustard (Brassica juncea) meal on intake, digestibility, growth performance and body composition of calves

Effects of feeding acid treated mustard (Brassica juncea) meal and untreated mustard meal (MM) as a source of protein on dry matter (DM) intake, digestibility, growth rate, body composition and blood constituents was studied in (Jersey×Sahiwal) crossbred growing calves. Diets consisted of oat hay offered ad libitum with a compound feed mixture (CFM) as a supplement to provide protein and other nutrients. CFMs were formulated using soybean meal (SBM), untreated MM or acid treated MM. Differences among treatment groups in DM intake of oat hay and in total DM intake as a percentage of body weight (BW) favoured (P<0.05) the SBM diet, whereas acid treated MM and untreated MM fed calves had similar DM intake. The feed conversion ratio was the lowest (P<0.05), and growth rate was highest (P<0.05), in calves fed SBM and acid treated MM diets. Serum albumin was lowest (P<0.05) in calves fed the untreated MM diet. Acid treated MM can replace SBM as a protein source without substantive detrimental effects on overall calf performance and has beneficial effects on performance of growing calves compared to untreated MM.