Feedlot Performance of Young Red Angus Steers Slaughtered at Different Body Weights

[摘要] - The feedlot performance of Red Angus steers, with initial age of eight months and 189 kg of initial live weight, fed to reach the slaughter weight (SW) of 340, 370, 400 or 430 kg, was evaluated. The number of days to reach the respective weight was 114, 144, 168 and 209 days, with 12, 13, 14 and 15 months of age. The animals were fed with a 13.13% crude protein diet, and roughage:concentrate ratio of 56:44. The average daily gain was 1.32, 1.27, 1.23 and 1.15 kg, respectively. Dry matter intake (DMI) expressed in kg/day/animal and metabolic weight, did not show significant relation with slaughter weight. When DMI was expressed per 100 kg of live weight a linear decline occurred (DMI/100 kg W= 3.599 - 0.003152SW) as the final weight increased. Body condition improved linearly with the final weight (Body condtion = 0.159 + 0.0103SW), while feed conversion worsen (FCDM = 1.585 + 0.01019SW), however it can be considered satisfactory, being respectively 5.09, 5.35, 5.55 and 6.04 kg of DM/kg of weight gain. In order to reach the minimum carcass weight and subcutaneous fat thickness required, the regression equation estimation showed that slaughter weight should be of 337 and 327 kg, respectively.

[学科分类] 兽医学

[关键词] Bos taurus;feed conversion;feed efficiency;food intake;slaughter weight;weight gain    IntroduçãoA prática da terminação de bovinos em sistema de confinamento é uma alternativa segura quando se deseja atingir determinados índices produtivos;por permitir melhor controle da dieta e monitoramento da resposta animal; além disso;o uso de alimentação conservada;praticamente;elimina os contratempos causados por adversidades climáticas e permite a utilização de subprodutos da indústria