Rodrigo Caetano de Abreu

Período de suplementação de ractopamina em dietas para suínos machos castrados em terminação

The study was conducted to determine the optimal period of supplementation of 20ppm of ractopamine in diets of finishing barrows. Fifty pigs, with initial weight of 65.85±4.34kg were used. The pigs were distributed in randomized blocks design of six treatments (supplementation of ractopamine for 0, 7, 14, 21, 28 and 35 days pre-slaughter), with four replications for treatments 0, 7, 14, 21 and 28 days and five replicates for the treatment supplemented by 35 days. Each experimental unit consisted of two animals. The feed conversion improved (P<0.05) and the hot carcass weight, the amount of lean meat and the index of carcasses increased linearly (P<0.05) with increasing period of ractopamine supplementation. The economic return for the amount of lean meat produced per animal improved linearly until the period of seven days of supplementation with ractopamine, from which remained at a plateau (P<0.05). Supplementation of 20ppm of ractopamine in the diet of finishing barrows during the 35 days improved feed conversion, increases the hot carcass weight, the amount of lean meat and the index of carcasses. The supplementation of 20ppm ractopamine in the diet of finishing barrows results in economic return for the amount of lean meat produced per animal regardless of the length of supplementation.

Ractopamina em dietas sem ajustes aminoacídicos para suínos machos castrados em terminação

Este estudo teve o objetivo de avaliar planos de suplementacao com ractopamina, em dietas sem ajustes aminoacidicos, para suinos machos castrados, em terminacao. Foram utilizados 72 suinos machos castrados, com peso inicial de 68,61 ± 3,89 kg, distribuidos em seis planos de suplementacao com duracao de 30 dias (0 ppm; 5 ppm; 10 ppm; 20 ppm; 5 ppm, durante 15 dias, seguidos por 10 ppm durante 15 dias; e 10 ppm durante 15 dias seguidos por 20 ppm durante 15 dias), com seis repeticoes e dois animais por unidade experimental. A suplementacao com ractopamina melhorou a conversao alimentar. A suplementacao com 5 ppm de ractopamina aumentou o ganho de peso diario. Os niveis de 10 e 20 ppm e as suplementacoes graduais reduziram o consumo de racao diario e de nutrientes. Nao houve influencia da suplementacao sobre o peso de carcaca quente e o comprimento de carcaca. A ractopamina reduziu a espessura de toucinho e aumentou a profundidade de musculo, o percentual de carne magra, a quantidade de carne magra e o indice de bonificacao das carcacas. A suplementacao de 5 ppm de ractopamina em dietas sem ajustes aminoacidicos melhora o desempenho e as caracteristicas de carcaca de suinos em terminacao, nos 30 dias pre-abate.

Perfil lipídico da carne e gordura de suínos alimentados com milheto

The aim of this study was to evaluate the replacement of corn by millet in the diets of pigs on the lipid composition and cholesterol from subcutaneous fat and meat. It was used 48 castrated males, distributed on randomized experimental blocks design, with four levels of millet in the diet (0; 25; 50 and 75%), six replicate of two animals each. It was analyzed the lipid profiles of fat and meat by gas chromatography and the amount of cholesterol in the meat samples was determined following the extraction methodology. The increased level of millet in the diet of pigs reduced (P<0.05) the concentration of myristic, palmitic, palmitoleic and heptadecanoic acids and increased the concentration of linoleic acid in subcutaneous fat. The inclusion level of 50.82% of millet in the diet allowed maximum deposition of linolenic acid in fat. Levels of millet did not change the fatty acid profile and cholesterol content in pork. The level of 42.09% inclusion of millet in the diet results in the highest rate thrombogenic meat.