Estimativa de componentes corporais ao abate através de medidas in vivo em ovinos

Abstract

The study aimed to identify the relationships between Body Mass Index (BMI), Frame, and Body Compactness in sheep prior to confinement and their pre- and post-slaughter body characteristics, including non-carcass components, in order to determine their potential as selection criteria for animals better suited to this finishing method. A total of 24 castrated male sheep, 16 months old, of undefined breed but predominantly Corriedale, with an initial body weight of 42.45 ± 4.45 kg, were used. The animals were housed in a masonry barn divided into pens measuring 9.24 m². Before entering confinement, they were evaluated for BMI, Frame, and Body Compactness. At the time of slaughter, live weight at slaughter (LWS) and live weight after fasting (LWF) were recorded. Immediately post-slaughter, hot carcass weight and non-carcass components were weighed. Carcasses were evaluated for conformation, fat cover, and yield, both objectively and at the processing facility. Data were subjected to Pearson correlation analysis (P ≤ 0.05) to assess linear associations among all variables. When significant correlations were observed between BMI, Frame, and/or Body Compactness (measured prior to confinement) and pre-slaughter (LWS and LWF) or post-slaughter traits (hot carcass weight [HCW], actual yield, and processing yield), regression equations were developed to predict the latter based on pre-confinement measurements. Statistical analyses were performed using Past software, version 3.20. BMI was correlated with the pre-slaughter traits LWS and LWF; however, correlation (r ≤ 0.54) and determination (R² ≤ 0.29) coefficients were low. Frame showed strong correlations with LWS, LWF, and HCW (r ≥ 0.82), along with high determination coefficients (R² ≥ 0.68). Similarly, Body Compactness was positively correlated with LWS, LWF, and HCW (r ≥ 0.73), with R² ≥ 0.54. None of the pre-confinement variables were significantly correlated with carcass yield (P ≥ 0.05). Frame and Body Compactness values assessed prior to confinement were positively associated with live weight at slaughter, live weight after fasting, and hot carcass weight, suggesting their potential as predictors of these performance traits. Therefore, Frame and Body Compactness can be effectively used as selection criteria for identifying animals more suitable for confinement-based finishing systems.