Rapeseed meal, maize-gluten feed and fish meal as protein supplements for maize silage given to growing/finishing Limousin × Holstein Friesian bulls

Abstract

AbstractIn each of three experiments, 60 Limousin × Holstein Friesian bulls, initially of 191, (s..e. 5·0), 177 (s.e. 5·5) and 210 (s.e. 7·2) kg mean live weight for experiments 1, 2 and 3 respectively, were offered maize silage ad libitum plus one of three barley-based, isonitrogenous compound diets containing 200 g rapeseed meal, 575 g maize-gluten feed or 100 g fish meal per kg fresh weight. Compound diets were given at the rate of 3·0 kg (fresh weight) per head per day up to 320 kg live weight and at 3·3 kg per head per day from 320 kg to 420 kg live weight. In experiment 3, when bulls were taken through to slaughter, the compound diet was further increased to 3·5 kg per head per day from 420 kg live weight to slaughter. Experiments 1 and 2 were conducted over 128 and 194 days, with mean live weights at the end of the experiments of 347 (s.e. 17·2) and 414 (s.e. 24·2) kg respectively. In experiment 3, bulls were slaughtered at 16 months of age at a mean live weight of 544 (s.e. 25·0) kg.In experiment 1, the fish-meal diet gave the highest rate of daily live-weight gain at 1·34 compared with 1·17 and 1·16 (s.e.d. 0·041) kg for rapeseed-meal and maize-gluten diets, respectively. In experiments 2 and 3, daily gains were similar on all treatments at 1·21, 1·19 and 1·26 (s.e.d. 0·036) kg and 1·06, 1·09 and 1·11 (s.e.d. 0·035) kg for the rapeseed-meal, maize-gluten and fish-meal diets respectively. Total daily dry-matter intakes did not show consistent trends: in experiment 1, intakes were 5·8, 5·6 and 5·8 kg/day, in experiment 2, 6·2, 6·2 and 6·3 kg/day; and in experiment 3, 7·1, 7·3 and 7·1 kg/day for rapeseed-meal, maize-gluten and fish meal, respectively. The higher intakes of dry matter in experiment 3 were due to the greater intakes of maize silage by bulls taken to heavier weights in this experiment.