Deptartment of Veterinary Biochemistry, College of Veterinary Science, Acharya N.G. Ranga Agricultural University, Rajendranagar, Hyderabad-500 030, India
Five complete diets were formulated without rapeseed meal (control, DI) or raw rapeseed meal (D2) or rapeseed meal treated with 0.5% copper sulphate (D3) or pressure cooked rapeseed meal (D4) or 0.5% copper sulphate followed by pressure-cooked rapeseed meal (D5) as protein supplement Diets were processed into mash and fed to growing ram lambs to study the effect of method of processing of rapeseed meal on growth, biochemical profile and vital organs. The Iambs fed on D2 showed lowered serum total protein, albumin, albumin: globulin ratio, cholesterol, urea, creatinine, thyroxine and haemoglobin and increased ALT levels. Further, the lambs of this group also exhibited the damage of vital organs viz., mild congestion in liver, hyaline casts in kidney and hypertrophy of the thyroid gland. The lambs fed with D3 and D5 also showed lowered serum albumin levels and higher ALT and AST levels reflecting the effect on vital organs, may be due to the excess copper sulphate used as a toxin binder to detoxify the rapeseed meal. Two animals from each group fed on D3 and D5 died after four months due to cumulative effect of copper toxicity. Lambs fed with D4 did not show any adverse effect on the health compared to other diets. These results revealed that pressure-cooking could be a safe method for detoxification of rapeseed meal and it can be used in livestock rations as protein supplement without any deleterious effect on growth, biochemical profile and vital organs.
