effect of sodium bentonite addition to diets containing cottonseed meal on apparent digestibility of nutrients and profitability of laying hens

the objective of this study was to evaluate the effect of cottonseed meal (csm) treated with sodium bentonite (sb) on laying hen profit and apparent digestibility of nutrients. a 3×3 factorial arrangement in a completely randomized design with 9 dietary treatments of 4 replicates consisting 3 levels of sb (0, 1 and 2%) and 3 levels of csm (0, 10 and 20%) were tested. nine mash diets were fed to 288 commercial hy-line w-36 hens from 51 weeks of age for 12 weeks. feeding 20% csm reduced apparent digestibility of organic matter and egg production and increased feed cost. inclusion of 10% csm did not have adverse impacts on nutrients digestibility and hen performance. interestingly, csm at the level of 10% increased economic profit and reduced excreta moisture. egg shell quality was not influenced by sb or csm. the sb significantly decreased apparent digestibility of dry matter and organic matter; however did not have deleterious effects on productive traits. in overall, diet with 1% sb and 10% csm resulted in the best performance and the most economic profit of laying hens.