Comparative evaluation of rumen-protected fat, coconut oil and various oilseeds supplemented to fattening bulls - 1. Effects on growth, carcass and meat quality

Growth performance, carcass and meat quality were determined in 36 fattenin g Brown Swiss bulls fed with maize silage-hay-concentrate based rations sup plemented with fats and various oilseeds. The concentrate diet in the contr ol group contained only barley and soybean meal, while the treated groups i ncluded, as partial replacement of the concentrate, rumen-protected crystal line fat, coconut oil, whole crushed rapeseed, sunflower seed or linseed, p roviding additional 3% fat of total ration dry matter. Animals were housed in groups of six with one representative of each treatment in a monofactori al design and feed was offered using transponder controlled equipments. Dai ly gains were similar for control, protected fat, rapeseed and linseed trea tments (1240 g/d on average), but were lower (P < 0.05) with sunflower seed (1135 g/d) and coconut oil (1038 g/d). Corresponding differences (P < 0.05 ) in carcass weights were observed. All fat supplemented groups had reduced rumen fluid protozoa counts (P < 0.05). Carcasses tended to be leaner with the fat supplements. Mostly no significant effects on other carcass qualit y (dressing percentage, conformation score) and meat quality traits (final pH, cooking loss, shear forces) as well as composition (dry matter, fat, co llagen) occurred. Consequently, rumen protected fat and some oilseeds can b e recommended to be fed to growing cattle as energy sources.