Resumo
O objetivo deste trabalho foi determinar o teor de fibra em detergente neutro (FDN) ideal que incremente positivamente as caracteristicas de carcaca e qualidade de carne de ovinos da raca Santa Ines terminados em confinamento. O experimento foi conduzido na Fazenda Experimental de Sao Goncalo dos Campos, pertencente a Escola de Medicina Veterinaria e Zootecnia da UFBA, entre setembro e dezembro de 2016. Foram utilizados 60 ovinos da raca Santa Ines, machos, nao castrados, com peso vivo medio inicial de 17 ± 1,5 kg. Os animais foram distribuidos num delineamento experimental inteiramente casualizado (DIC), com doze repeticoes. As dietas foram compostas por feno e concentrado, sendo os tratamentos representados pelos niveis de FDN (20, 32, 44, 56 e 68%). Houve influencia da dieta (p<0,05) sobre o peso de carcaca quente (PCQ) e peso de carcaca fria (PCF) onde o PCQ se apresentou de forma linear decrescente PCF se apresentou de forma quadratica. Os pesos de carcaca quente e fria obtiveram menores valores quando submetidos ao nivel maximo de FDN (68%) sendo os valores 10,82 kg e 10,78kg respectivamente, e os maiores para as dietas com nivel de 20% e 32% de FDN sendo 18,31 kg e 18,30 kg para PCQ e 18,26 kg e 18,27 kg para PCF. As dietas com diferentes niveis de FDN ocasionaram diferenca (P<0,05) nas porcentagens de proteina, a qual se apresentou de forma quadratica com ponto minimo ao nivel de 56,79%. Ja em relacao a conformacao da carcaca, o ponto maximo de inclusao de FDN na dieta foi encontrado ao nivel de 29,24%, resultando no valor aproximado de 4,18. Ja para espessura de gordura o ponto maximo de inclusao de FDN foi encontrado ao nivel de 33,53% o que nao influenciou significativamente (p>0,05). Os ovinos da raca santa Ines terminados em confinamento podem receber dietas contendo baixos niveis de FDN sem que as mesmas afetem negativamente as caracteristicas de carcaca e qualidade da carne. Os niveis de 27 a 30% de FDN na materia seca da racao foram os mais adequados para terminacao de ovinos.
The objective of this study was to determine the ideal neutral detergent fiber (NDF) content that positively increases the carcass characteristics and meat quality of Santa Ines sheep finished in confinement. The experiment was conducted at the Experimental Farm of Sao Goncalo dos Campos, belonging to the School of Veterinary Medicine and Animal Science of UFBA, between September and December 2016. Six hundred Santa Ines sheep were used, male, not castrated, with initial mean live weight of 17 ± 1.5 kg. The animals were distributed in a completely randomized experimental design (DIC), with twelve replicates. Diets were composed of hay and concentrate, and treatments were represented by NDF levels (20, 32, 44, 56 and 68%). There was dietary influence (p <0.05) on the carcass weight (PCQ) and cold carcass weight (PCF) where the PCQ presented linearly decreasing PCF was presented in a quadratic form. The hot and cold carcass weights obtained lower values when submitted to the maximum NDF level (68%), being the values 10.82 kg and 10.78 kg respectively, and the highest for the diets with a level of 20% and 32% of NDF being 18.31 kg and 18.30 kg for PCQ and 18.26 kg and 18.27 kg for PCF. Diets with different levels of NDF caused a difference (P <0.05) in protein percentages, which presented a quadratic form with a minimum point at the level of 56.79%. Regarding the conformation of the carcass, the maximum inclusion point of NDF in the diet was found at the level of 29.24%, resulting in an approximate value of 4.18. As for fat thickness, the maximum inclusion point of NDF was found at the level of 33.53%, which did not significantly influence (p> 0.05). Santa Ines lambs fed in feedlots may receive diets containing low levels of NDF without adversely affecting the carcass characteristics and meat quality. The levels of 27 to 30% of NDF in the dry matter of the ration were the most suitable for sheep termination.