Digestion in sheep of diets containing barley chemically treated to reduce its ruminal degradability

Nigerian processed cottonseed meal was substituted for 0, 25, 50, 75 and 100 % portions of dietary groundnut cake on an equi-protein basis. The diets were fed to 50 Large White and Large White × Landrace crossbed pigs from 13.9 kg average weight to 70 kg liveweight in a bi-replicate single-way classification trial. Average daily gain and average daily feed consumption were 0.51, 0.52, 0.53, 0.55 and 0.56 kg; and 1.67, 1.77, 1.85, 1.84 and 1.82 kg for the respective diets. Feed/gain ratios ranged from 3.25 to 3.49. No significant differences between diets were seen for either of these parameters. Neither the gross tissue nor the jointed carcass proportions were significantly affected by cottonseed meal substitutions. The mean fresh weights of the liver and lungs decreased with increasing levels of dietary cottonseed meal but the differences were not significant. None of the pigs showed symptoms of gossypol intoxication. The data suggest that some of the Nigerian-processed cottonseed meals can be combined in various proportions with groundnut cake to supply protein, or used singly, up to 20 %, in diets for weaner-grower pigs.