Use of Castor Bean Meal, Biodiesel Industry Coproduct, in A Lamb Production System Using Creep-Feeding in Brazil

SIMPLE SUMMARY: Economically, feed costs are the most expensive variable in the ruminant industry. Therefore, finding an alternative feed resource to decrease these costs is necessary. Castor bean is an oilseed used in the growing biodiesel industry from which the castor bean meal is obtained; however, the ricin content of the castor bean meal may cause animal poisoning. Thus, it is necessary to detoxify the castor bean meal before using it in animal feed. A creep-feeding method is a supplement to the actual alimentation of young animals and as a complement; its economic value must be lower. This study aimed to evaluate the replacement of soybean meal by detoxified castor bean meal on intake, digestibility, body weight gain, and creep-feeding method effectiveness using castor bean meal in lambs. It was found that replacing soybean meal by detoxified castor bean meal does not compromise the development of animals, while the use of creep feeding positively affects their development. The soybean meal can be replaced by detoxified castor bean meal in a creep-feeding method for lambs. ABSTRACT: This study aimed to evaluate the replacement of soybean meal by detoxified castor bean meal on the intake and digestibility of nutrients, body weight gain, carcass yield, physiological and urinary parameters, and creep-feeding method effectiveness. For this trial, 43 male lambs were used, Dorper × Santa Inês, with an average initial body weight of 7.95 kg, 15 days old. Lambs were distributed in a randomized block design. Five experimental diets were provided: Without supplementation, with supplementation but without the use of castor bean meal, and with gradual levels of replacement of soybean meal by detoxified castor bean meal (33%, 67%, and 100%). Higher values of DMI and nutrient digestibility (p < 0.05) were observed for animals that received supplements. The milk intake did not differ among the diets. The DMD showed a linear effect, while NDFD had a quadratic effect, depending on castor bean meal inclusion. The carcass yield did not differ between experimental diets. There was no significant effect on the urinary volume and metabolites investigated. In conclusion, the replacement of soybean meal by detoxified castor bean meal does not compromise animals’ development. Besides, the creep-feeding method positively affects lamb development, with higher body weight gain for supplemented animals.