Growth, yield of carcass and biochemical composition of meat and fat in nutria (Myocastor coypus) reared in an intensive production system

Growth, carcass yield and proximate composition were determined in intensively reared nutria (Myocastor coypus) fed different levels of protein. Growth, food intake and food utilization efficiency were not significantly affected, within the same sex, in animals receiving 16%, 19% or 22% of protein in the diet. Males consumed the same amount of food as females but had greater live and carcass weights at slaughter age than females. Males had the highest meat yield and females had the highest fat content. Independent of dietary protein level, the pectoral muscles of all animals ranged from 19.2% to 23.6% protein, 1.97% to 2.47% total lipids, and 70.1 to 72.0 mg of cholesterol in 100 g of tissue. In the thigh muscles, the observed ranges were between 21.4% and 22.9% in proteins, 1.83% and 2.07 in total lipids and 69.9 and 71.0 mg of cholesterol in 100 g of tissue. The determination of classes of lipids shows more phospholipids contents in animals receiving 16% of protein in diet.