Effects of the gossypol at different levels in diet of heifers Nelore
ABSTRACT. Piau-Junior R., Ribeiro E. de A., Quessada A.M., Ribeiro E. de A. & de Almada A.F.B. [Effects of the gossypol at different levels in diet of heifers Nelore.] Efeitos do gossipol em diferentes níveis na dieta de novilhas Nelore. Revista Brasileira de Medicina Veterinária, 38(Supl.1):120-126, 2016. Programa de Pós-Graduação em Ciência Animal, Universidade Paranaense, Campus Umuarama, Praça Mascarenhas de Moraes, 4282, Zona III, PR 480, S/n, Km 14, Umuarama, PR 87502-210, Brasil. E-mail: firstname.lastname@example.org The use of cottonseed in ruminant feed has aroused interest because it is an important energy and protein source as supplemental fodder. However, the cotton and your by-products have an anti-nutritional factor, the gossypol, which may have a toxic effect on ruminants. In Brazil there is still a lack of studies on animals, about the toxicity of the gossypol, and most studies with cotton in ruminant feed is performed in dairy cows. Thus, the objective of this study was to observe the effect of the addition of gossypol in the diet of Nelore heifers. 15 heifers were used receiving a daily diet consisting of 12 kg of silage with elephant grass and 100g of mineral supplement. The animals were divided into three groups. In the first group (A, control), the diet contained no gossypol; in the second group (B) was added in the diet, 900 ppm free gossypol; and in the third group (C), the diet contained 1500 ppm of free gossypol. Prior to administration of the diets and after the experiment began, animals were weighed biweekly (0, 15, 30, 45, 60 and 75 days, total of six weighings). Elapsed 10 weeks the animals were slaughter, and liver, heart and spleen were weighed, and samples of these organs were collected for preparation of histological sections. The animals were examined daily and there was no clinical signs of intoxication. In relation to weight gain, there was no statistical difference between the treated animals and the control group. At necropsy, gross changes were not seen in heart, spleen, liver, kidney and lungs. The weight of liver, heart and spleen showed no differences between groups. There were no clinical signs of renal injury but it was observed histopathologically discrete renal injury. The other organs showed no histological lesions. It was concluded that heifers may be fed with by-products of the cotton without showing clinical poisoning, since the level of gossypol does not exceed 1,500 ppm.