Evaluation of cottonseed meal in Coturnix quail diets

Abstract

Experiments were conducted to determine the elects of cottonseed meal (CSM) on growth and performance of Coturnix quail when diets are formulated on a digestible amino acid basis in the presence of high and low concentrations of iron. Concentrations of total, (+)- and (-)- isomers of gossypol were determined in heart, liver and blood plasma. For Experiment 1, various concentrations (0, 7, 14, 21 and 28%) of an expander solvent cottonseed meal (CSM) were fed to Coturnix quail using feed-grade mono-dicalcium phosphate (21% Ca, 16% P, 1.5% Fe) as a source of inorganic phosphorous. All diets were formulated using true digestibility coefficients for essential amino acids. There were no significant effects of CSM on body weights, feed intakes, feed conversions or mortality. The CSM levels did not significantly affect relative heart or liver weights. Total, (+)- and (-)-gossypol concentrations in plasma, heart and liver increased as levels of gossypol in the diet increased. Experiment 2 was designed to determine maximum safe levels of an expander solvent cottonseed meal (CSM) in Coturnix quail diets while utilizing USP-grade mono-dicalcium phosphate (23.7% Ca, 18.3% P, .025% Fe). There were no significant differences seen in mortality or feed conversion. Tissue and serum gossypol increased as dietary levels of CSM increased. During Week 5, quail fed 28% CSM had significantly lower body weights than all other treatments. However, by Week 6, there were no significant differences in body weights among treatments. In Experiment 3, to determine if the use of cottonseed in a low iron diet would alter blood iron concentrations, quail were fed diets with either feed-grade phosphorous or USP-grade phosphorous and ground cottonseed meats to achieve either 0 ppm gossypol or 400 ppm gossypol. No significant differences were seen among treatments due to the elects of cottonseed. When fed a diet formulated on a true digestibility basis, up to 28% CSM may be safely used when utilizing a high-iron phosphorous source and up to 21% CSM when utilizing a low-iron phosphorous source without affecting performance or serum iron concentrations.