Beef quality of young Angus×Nellore cattle supplemented with rumen-protected lipids during rearing and fatting periods.

This work evaluated the beef quality parameters of 108 bulls randomly administered to three treatments during rearing in pastures and two treatments during fatting in feedlots, including mineral and rumen-protected lipids. Meat and fat color, cooking yield, shear force, sensorial traits and chemical and fatty acid compositions were evaluated. Generally, the beef quality parameters were not affected by the rumen protected lipids; however, supplementation with rumen-protected lipids during the rearing period yielded darker beef and brighter fat and increased beef tenderness in meat aged for 28days compared to the meat from animals that received only mineral supplementation. In addition, the percent of meat polyunsaturated fatty acids was negatively affected by the inclusion of protected lipids, yielding 5.58 and 3.72% in animals fed with and without rumen-protected lipids, respectively, during the fatting period.

Desempenho e características da carcaça de bovinos alimentados com dietas com caroço de algodão / Performance and carcass traits of steers fed diets containing whole cottonseed

Avaliou-se o efeito da adição de caroço de algodão à dieta de bovinos confinados sobre o desempenho animal e características da carcaça. Usaram-se 36 novilhos Nelore com médias de idade e peso vivo inicial de 20 meses e 333,5kg. Os animais foram confinados e receberam dietas com os seguintes teores de caroço de algodão: 0; 14,35 por cento; 27,51 por cento; e 34,09 por cento na matéria seca da dieta. O ganho de peso diário, peso vivo final e consumo de matéria seca diminuíram linearmente com o aumento da proporção de caroço de algodão na dieta. Não foi observado efeito sobre o ganho de peso total ajustado ao consumo. Os pesos da carcaça e do contrafilé diminuíram linearmente com o aumento da proporção de caroço de algodão na dieta. Não foi observado efeito do teor de caroço de algodão sobre a área de olho de lombo. A espessura de gordura de cobertura do dorso e da garupa diminuíram com o aumento do teor de caroço de algodão. Observou-se correlação de 0,62 entre as duas medidas de gordura. A adição de caroço de algodão à dieta de bovinos de corte não se mostrou vantajosa, pois diminuiu o desempenho animal e a deposição de gordura na carcaça.

The purpose of this experiment was to evaluate the effect of adding whole cottonseed to the diet of feedlot cattle over the performance and carcass traits. Thirty six Nellore bullocks were used, with an average age of 20 months and average initial weight of 333.5kg. The animals were raised on feedlot and fed diets with the following content of whole cottonseed: 0; 14.35 percent; 27.51 percent; or 34.09 percent on a dry matter basis. The daily weight gain, final weight and dry matter intake decreased linearly as the proportion of cottonseed increased. No effect of cottonseed on total weight gain adjusted for intake was observed. Carcass and ribeye weights decreased linearly as cottonseed content increased. No effect of cottonseed content was observed for ribeye area. In contrast, back fat and rump fat thickness decreased as cottonseed content increased. A correlation of .62 was observed between back fat and rump fat. Adding whole cottonseed to beef cattle diets did not prove advantageous because it reduced animal performance and carcass fat deposition.