Effect of substitution of groundnut with high glucosinolate mustard (Brassica juncea) meal on nutrient utilization, growth, vital organ weight and blood composition of lambs

Twenty-four 14-day-old weaner Avivastra (Russian Merino x Nali) male lambs were maintained for 180 days on ad libidum Cenchrus (Cenchrus ciliaris) hay and concentrate mixture (CM) contained groundnut meal (control) and mustar d meal (MM group) as major protein source. The two CMs were isonitrogenous (21% CP) and isocaloric (2.78 Mcal ME kg(-1) DM), while, CM fed to MM group contained 24.6 mg glucosinolates g(-1) DM. Digestibility of nutrients was similar (P > 0.05) in the two groups except for CP and hemicellulose, which was higher (P < 0.05) in control. Urinary N loss was higher (P < 0.01) in control than in MM group, whereas N retention (% of N intake and absorbed) was higher (P < 0.01) in MM group compared to control. Dry matter (g kg(-1) BW) and glucosinolate intakes were higher in MM fed group, whereas DCP and ME intakes were similar (P > 0.05) in the two groups. Average daily gain ( ADG) was, however, 22% higher (P < 0.01) in control than in MM group. Hemog lobin and albumin contents were lower (P < 0.01) in MM group than in contro l. Serum thiocyanate content was 26.7 mug g(-1) in MM fed group, while it w as not detected in control group. Thyroid weight was higher (P < 0.01) whil e liver and kidney weights were lower (P < 0.01) in MM group. Meat from dis sected carcass of control group contained more protein and less fat, wherea s the reverse was noticed in MM group. it is concluded that feeding mustard meal as protein supplement reduced growth rate and induced iodine deficien cy. Carcass of lambs fed mustard meal had more fat and less protein. (C) 20 01 Elsevier Science B.V. All lights reserved.