Resumo:
Aimed to evaluate the match between levels of CaO and autoclaving times on the efficiency of detoxification process of castor meal and testing inclusion levels in lambs feeding. Detoxification capacity through interactions between the time of autoclaving and the amount of CaO was evaluated. It was used a 5x2 factorial design, five levels of calcium oxide (0, 10, 20, 30 and 40 g / kg) and two times in autoclaving (15 and 30 minutes), with five replicates per treatment. The treatment with 10g of calcium oxide / kg of castor oil meal and autoclaving for 30 minutes promoted the disappearance of the bands that represent the subunits of ricin, being the most efficient method because less CaO was used in the process. Therefore, this method was used to detoxify the castor bean meal used for formulation of the experimental diets. 40 crossbred male sheep were used, with average weight of 25 ± 2,96kg, in a completely randomized design with four treatments and ten replicates. The diets consisted of 0, 10, 20 and 30% inclusion levels of castor meal on dry matter. Diets were formulated to be isonitrogenous, and forage:concentrate ratio was 50:50. The inclusion of castor meal in the diets of growing lambs until the level of 30% of the total diet did not affect the intake of dry matter and crude protein, averaging 1.194g and 191g respectively. However, promoted increases in intake of ether extract and neutral detergent fiber on 17% and 19% respectively. However, the consumption of non- fibrous carbohydrates linearly decreased, around 31.8%. There was a linear decrease in the digestibility of dry matter and carbohydrates both the fiber and the non-fiber fraction, with the inclusion of detoxified castor meal. However, CP and EE digestibility coefficients have not changed. The performance data of sheep fed diets containing castor meal indicated a decreasing linear trend for the variables final body weight gain in total weight and average daily gain. The levels of hepatic enzymes GGT, AST and ALT were not influenced by the inclusion of detoxified castor meal, just as the levels of albumin, cholesterol and triglycerides. Based on the evaluated results is possible to reduce the level of CaO to 10g / kg of castor meal and the autoclave time to 30 minutes using the mixed method of detoxification, and later include up to 30% of castor meal in diet of lambs.
