Fattening performance and carcass traits of Imported Simmental bulls at different initial fattening age

Abstract

Fattening performance is one of the most important traits in cattle breeding. These traits are closely associated with adequate initial weights and slaughter endpoints. In this context, the aim of this study was to investigate optimum initial fattenning age of Simmental young bulls and to evaluate the effects of initial fattening age on fattening performance and carcass characteristics. Seventy five animals were purchased from a single commercial farm where they had been reared under identical production conditions and were allocated into four groups according to age and live-weight as follows: Group I (4 monts of age), Group II (6 months of age), Group III (8 months of age), and Group IV (10 months of age). All animals were housed in semi-open pens and were fed ad libitum with the same appropriate diet for nine months. After reaching the target final weights, the animals were slaughtered and carcass traits including hot and chilled carcass weights, dressing percentage, and chiling loss were determined. Morever, performance traits including total weight gain, feed conversion rate, average daily weight gain, and dry matter intake were estimated. Results revealed that the initial fattening age of bulls showed significant effects on total weight gain and chilled carcass dressing. In this context, Group I was characterized by the highest total weight gain, whereas, Group IV had the highest values for chilled carcass dressing. During early fattening periods, first 3 months, average daily weight gain was significantly different among the treatments. Concerning the latter fattening periods, average daily weight gain seemed to be rather variable among the initial fattening groups but these differences were not substantiated by statistical analyses Additionally, spring season was characterized by higher means of average daily weight gains. This study provides a detalied analysis of initial fattening age influences on fattening performance in Simmentals and the present results may be useful for evaluating the adequate management practices in cattle farms. Moreover, this study may have a potential to influence recent strategies for importation of cattle.