NUTRITIONAL-EVALUATION OF LOW GLUCOSINOLATE MUSTARD MEALS (BRASSICA-JUNCEA) IN BROILER DIETS

Experiments were conducted to evaluate the nutritional value of meal d erived from low glucosinolate cultivars of mustard (Brassica juncea) i n comparison to samples of canola meal (Brassica napus, Brassica rapa) . Samples of Brassica seed (four B. juncea, one B. napus, and one B. r apa) were processed using laboratory procedures to produce oil-extract ed meals, which were examined for composition (DM basis), and nutritio nal value for broiler chickens as judged by nutrient retention (AME(n) , ileal protein digestibility) and performance. Meals derived from B. juncea contained more CP and less total dietary fiber (TDF) on a dry b asis than either B. napus or B. rapa, 45.9 vs 44.6 and 43.1% CP and 27 .22 vs 29.47 and 29.67% TDF, respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) levels for B. juncea and B. rapa mea ls were similar to each other, but lower than those of B. napus, 12.79 and 13.20 vs 20.6% ADF, and 21.15 and 19.58 vs 29.47% NDF respectivel y. Brassica juncea meals contained more glucosinolates than B. napus a nd B. rapa, 34.3 vs 21.8 and 25.5 mu mol/g total glucosinolates, respe ctively. Brassica juncea meals were equal or superior to B. napus and B. rapa meals for AME(n) and apparent ileal protein digestibility. Sim ilarly, broilers fed B. juncea meals grew as quickly and converted fee d to BW gain as efficiently to 21 d of age as those birds fed B. napus and B. rapa meals. Feeding meal from B. rapa reduced growth rate and gain to feed ratio. In conclusion, the nutritional value of meal from low glucosinolate mustard was equal or superior to that of canola meal samples derived from B. napus and B. rapa cultivars.