Effect of the management system on the yield and conformation in the carcass of goat Payoya kids

Abstract

The objective of this study was to evaluate the effect of management system (conventional vs. organic) on carcass yield and carcass quality characteristics of Spanish Payoya goat kids. Twentyfour male kids (12 from conventional system and 12 from organic system) were used. Kids in both groups were born from twin births and during a reduced period of time (October, 2006). They were raised with natural milk and slaughtered at 8.9 kg of farm live weight. Fasting losses, empty body weight (EBW), hot carcass weight, chilling looses and external carcass fat measurements were recorded. Different carcass yield measurements were calculated: real, farm (CFY), slaughter, commercial and biological yield. Measurements of carcass conformation: leg length, hind limb width, hind limb perimeter (HLP), chest depth, chest width (CW), carcass external length, carcass internal length, chest perimeter, OS1 and OS2, were carried out to obtain different indexes: fleshiness, carcass compactness, leg compactness, chest roundness (CRI), relation carcass depth/length (RDL), relation carcass length/width, relation depth/width and bone index. The effect of production system was evaluated on each studied variable. The results shows some differences in fasting losses (3.83 vs. 5.74 %; p<0.001), in EBW (8.32 vs. 7.98 kg; p<0.01) and in CFY (52.7 vs. 50.5%; p<0.01), for conventional and organic system, respectively. For carcass conformation measurements we found differences (p<0.001) in HLP (31.1 vs. 27.9 cm) and in CW (10.7 vs. 9 cm), for conventional and organic system, respectively. Significantly differences were established in some of the calculated indexes, like CRI (0.62 vs. 0.54; p<0.01) and the RDL (0.44 vs. 0.46; p<0.05), for kids from conventional and organic production systems, respectively. There were no significant differences in the rest of the parameters included in the present study between production systems. We can conclude that Payoya kids raised in organic production system differ little, particularly in carcass yield and conformation, respect to kids raised in a conventional production system.