Effects of weight and age on carcass yield and conformation of cattle

The aim of this research was to analyse effects of weight and age of dairy cattle breeds and their crossbreeds (423 bulls, 492 heifers and 567 cows) on carcass yield and conformation scores according SEUROP standard data. All animals were divided into groups according to pre-slaughter weight (50 kg interval) and according to age (2 months interval). For research, average ages of the animals were: bulls 19 months, heifers 20 months and cows 38 months. The highest average weight was determined in cows 521.2 kg, followed by heifers 461.7 kg and the least got bulls 456.2 kg however, on the average carcass yield bulls got the highest value of 51.3 percent, 50.1 percent of heifers and the least 47.8 percent of cows. When animals pre-slaughter weight an average increase of 50 kg, the carcass yield of bulls on average increased by 11.1 percent, of heifers - 0.72 and cows - 0.94 percent. In all studied groups of animals were obtained weak correlation links between age of animal and carcass yield. The strongest correlation links were obtained between the animal's weight and carcass weight of bulls (r = 0.93, p <0.001), heifers (r = 0.94, p <0.001) and cows groups (r = 0.91, p <0.01). It was revealed that, if age of cattle moderately increases for 2 months, then there was a moderate increase on carcass yield such as 0.21 percent in heifers (p <0.05) and 0.12 percent in cows groups (p <0.05). This relationship was not statistically significant in the bulls group. Mostly, the O muscularity class of carcasses were evaluated in all analysed animals groups, both depending from pre-slaughter weight and age. In the group of bulls evaluated O muscularity class carcasses were found moderate (76.8 percent), heifers (74.3 percent) and in group of cows (49.7 percent). However, a trend was observed that with animal's weight and age improved carcass yield and arise carcass muscularity class.