THE EFFECT OF STOCKING DENSITY ON CARCASS TRAITS, MUSCLE FIBRE PROPERTIES AND MEAT QUALITY IN RABBITS

摘要

The aim of the present work was to evaluate the effect of stocking density on the biceps femoris (BF) muscle fibre properties, meat quality and carcass traits of Czech White rabbits. A total of 20 rabbits (40 d old, 10 rabbits per treatment, sex ratio 1/1) were reared in cages at different stocking densities (10 rabbits/m(2) or 4 rabbits/m2) for 49 d. There were no significant differences between groups with regard to hot carcass weight (HOW) or dressing-out percentage. The proportions of both perirenal (9.5 vs. 15.9 g/kg HCW; P=0.010) and total dissectible fat (14.9 vs. 25.1 g/kg HCW; P=0.001) were lower in rabbits reared at the lower stocking density. No significant differences in ultimate pH values, meat colour or proximate composition were observed. The hind leg meat of rabbits reared at the lower stocking density contained significantly less lauric acid (4.6 vs. 6.7 mg/100 g of muscle; P=0.008), myristic acid (52.2 vs. 64.4 mg/100 g of muscle; P=0.033) and Docosahexaenoic acid (0.3 vs. 0.5 mg/100 g of muscle; P=0.024). Significantly higher percentages of beta R fibres (16.3 vs. 6.5%, P=0.001) and alpha R fibres (24.5 vs. 14.2%; P=0.001) and a significantly lower percentage of alpha W fibres (59.2 vs. 79.3%; P=0.001) were also observed in these rabbits. The mean cross-sectional area (1882 vs. 2744 mu m(2); P=0.001) and diameter (47.9 vs. 58.5 mu m; P=0.001) of,BR fibres were smaller in rabbits reared at the lower stocking density. Thus, the different stocking density used in our study modified fibre type distribution and fibre histomorphological characteristics of the biceps femoris muscle of rabbits and significantly decreased concentrations of lauric acid, myristic acid and docosahexaenoic acid in the hind leg meat.