Carcass characteristics of pasture-finished Nellore cattle under different nutritional plans

The aim of this study was to evaluate different supplementation strategies on carcass characteristics of Nellore cattle finished on a Marandu grass pasture during the rainy season. The experimental period (EP) was from December 2013 to May 2014. Seventy-two uncastrated animals with 409?18 kg body weight (BW) were supplemented with the following nutritional strategies: mineral supplement (MS, ad libitum) for 140 days of the EP; energy supplement (ES, 7 g/kg BW) for 140 days of the EP; and MS ad libitum for the first 70 days of the EP and high supplementation (20 g/kg BW) in the last 70 days of the EP (MS-20). A randomized block experimental design was adopted, with BW as the blocking factor, and experimental unit as the paddock (4 paddocks/treatment, 6 animals/paddock). At the end of the EP two animals from each paddock were slaughtered in a commercial packing plant. Half-carcasses were weighed and chilled (0-4 ?C) for 24 h to obtain the hot carcass weight (HCW), cold carcass weight (CCW), chilling loss, and hot carcass yield (HCY). Loin-eye area (LEA) and backfat thickness (BFT) were determined on the left half-carcass, after sectioning the longissimus muscle between the 12th and 13th ribs. Animals that received MS-20 showed 355 kg HCW, 350 kg CCW, and 59% HCY; these values were 7%, 6%, and 3% higher than those of cattle fed ES, as well as 26%, 26%, and 11% higher than animals consuming MS only (P < 0.01). Chilling loss was not influenced by the strategies, averaging 1.8% (P = 0.40). Nutritional plan MS-20 provided a BFT of 3.21 mm, which was 1.62 mm higher than that of the animals on the other strategies (P < 0.01). The strategies that provided greater nutrient intake led to a larger LEA (P < 0.01), which was 21% larger than that obtained with MS. Strategies that provide greater nutrient intake allow animals to be finished with more adequate carcass characteristics.