PSVII-4 Effect of the residual gain and genetic group on body chemical composition of water buffaloes

Abstract

This study evaluated the effect of residual gain (RG) on body chemical composition of water buffaloes of three genetic groups (GG:Jafarabadi, Mediterranean, and Murrah) and verify the presence of chemical variables related to this efficiency measure. One-hundred-forty-eight non-castrated male (338.29 ±64.16 kg initial body weight; 370 ±28 days of initial age) from two similar experiments were used. The animals remained in feedlot and were slaughtered after 240 days (adaptation+trial periods). The RG was calculated considering 84 days after adaptation period. After the slaughter the empty body weight (EBW) of each animal was obtained and the left half-carcasses were dissected into muscle, fat, and bone, after 24h of cooling. The chemical composition [moisture, crude protein (CP), ether extract (EE), and ash] of each ground tissue was analyzed by the classical method. The body CP was also determined based on CP fat-free dry matter (CPFFDM). Data were analyzed using MIXED procedure in SAS. The class of RG, genetic group, and the resulting interaction were tested as fixed effect and year as a random effect. The variable results are reported as kg of EBW. There was no interaction effect (P ≥ 0.11) for the variables studied. Effect of class of RG was detected for the variables EBW (P = 0.021), water (P = 0.016), and EE (P = 0.035), while tendency was observed for CP (P = 0.074), for which animals classified as more efficient for residual gain demonstrated high values (Table 1). Furthermore, there was effect of GG for EBW (P = 0.002), water (P < 0.001), and CP (P = 0.014) variables. Tendency of GG effect was observed for ash (P = 0.085) and EE (P = 0.057). Jafarabadi showed high values for all the variables cited. In conclusion, there are difference in the body chemical composition of water buffaloes according to the animal efficiency evaluated by residual gain, as well as according to genetic groups. Supported by FAPESP (#2014/05473-7).