Anotace:
The aim of this paper was to evaluate the influence of birth weight and weaning weight on selected fattening, carcass, physical technological parameters and proximate composition of Longissimus thoracis et lumborum muscle from forty-five Holstein bull calves. Effect of birth weight: group1 (mean 36.98 kg), group 2 (mean 38.61 kg), group 3 (mean 41.11 kg) and weaning weight: group A (mean 88.54 kg), group B (mean 97.56 kg), group C (mean 116.09 kg) on parameters of Holstein veal production were examined. Each group was consisted of 15 animals. Slaughter weight, weight gains, body measurements, carcass conformation, retail yield (meat, trimmed fat, bones), and meat characteristics 24 hours and 7 days post mortem (pH, drip loss, shear force, colour, chemical composition) were studied. Calves of group 2 had highest lifetime average daily gains. Among monitored groups, significant effect of birth weight and weaning weight on hip height and heart girth were revealed. Dressing percentage (P<0.05) and carcass weight differed (P>0.05) little due to weaning weight. Calves of lighter birth weight had the least retail meat yield, but the most bones in carcass. Little effect of weaning weight on protein content (P<0.05) and energy value (P<0.01) or birth weight on energy value (P<0.05) of Longissimus muscle was revealed. Effect of birth weight or weaning weight on worsening or improving of physical technological traits of veal Longissimus muscle was not clear. Significantly different pH 24 hours post mortem was found in higher birth weight (P<0.01) and lower weaning weight (P<0.05). Parameters of meat colour – lightness and redness were not influenced by birth weight, but significantly affected by weaning weight (P<0.05). Content of palmitic acid was affected by both – birth weight and weaning weight (P<0.01). No interactions between birth weight or weaning weight were evident for resulted fattening, carcass, yield, physical technological and qualitative traits of calves.