EVALUATION OF 7 GENETIC GROUPS OF RABBITS FOR CARCASS TRAITS

Three hundred eighty-five growing rabbits representing seven genetic g roups were evaluated for carcass traits. Both sexes of two parities we re analysed to determine the effects of straight and cross breeding as well as parity on carcass traits. Genetic groups were New Zealand Whi te (NZW), Californian (CA) and German Large White (GLW) as purebreds; NZW x CA, CA x NZW, GLW x Fl {GLW x (NZW-CA) or GLW x (CA-NZW)} as ter minal crossbred (TX) and Fl x Fl as crossbreds (buck:doe). At 12-13 we eks of age live body weight st slaughter (after 24 h fasting) averaged 2488, 2484, 2506, 2505, 2512, 2503 and 2500 g; dressing percentages w ere 61.2, 61.6, 61.5, 61.5, 61.5, 60.9 and 61.5% respectively. There w ere not significant differences among genetic groups for dressing perc entages (total edible parts together). Sex was not important (p less t han or equal to 0.01) for all traits except offals which increased in females. Parity as source of variation was not important (P less than or equal to 0.01) for all traits except skin, feet and loin percentage s which increased in fryers of 1(st) parity while hind increased in fr yers of 2(nd) ones. Interactions among main effects were not significa nt for all traits except some of which differed significantly in main effects. Direct and maternal heterosis (H-NZW x CA(E) and H-NZW x CA(M )) were estimated for carcass traits and varied between negligible neg ative or positive values (except abdominal fat). Regarding crossbreedi ng effects on carcass yield, it revealed that generally low benefit of single or double crossbred rabbits.