Influence of Protein Source on Toxicity of Gossypol in Swine Rations

The results of an investigation to determine the effect of protein source on toxicity of gossypol in swine rations are presented. Peanut and soybean meal were used as the sources of supplemental protein in Experiment I and cottonseed and soybean meal in Experiment II. Cottonseed meats were added to the rations containing each source of protein to obtain graded levels of free gossypol. Six pigs were individually fed each ration. The toxicity of free gossypol, as measured by feed intake, gain and mortality of swine was influenced by both the source of protein and the level of free gossypol. There was a significant (P<0.05) protein-source × level-of-free-gossypol interaction associated with feed consumption and daily gain. Soybean meal rations gave superior performance to peanut or cottonseed meal rations at all levels of free gossypol. Efficiency of feed utilization was not significantly affected by gossypol addition to the ration. The mortality rate was lower for pigs fed soybean meal rations than for pigs fed peanut or cottonseed meal rations.