Further Observations in Eliminating the Toxicity of Cottonseed Meal

Abstract

Summary A study was made of the effects of feeding cottonseed meal rations to experimental animals when the meal constituted from 35 to 45 per cent of the diet. Growth and reproduction records of the animals were obtained over a period of five to six months. Three different cottonseed meals whose gossypol and d-gossypol contents had been estimated by chemical methods were employed and fed in three different forms; raw or as bought on the market, ether-extracted, and autoclaved. The meals were prepared in these forms for the purpose of altering their gossypol contents. The raw meals, which probably contained some free gossypol in the same form as it is found in the seeds although only traces could be detected by chemical methods, had a pronounced toxic effect as revealed in the slow growth of the animals and poor reproduction. Ether extraction of the meal which removes some of the gossypol in a proven toxic form, aided but little in preventing these injurious effects indicating that the insoluble form of gossypol which occurs in relatively large amounts is also toxic. Autoclaving the moist meal which reduces its toxicity but did not entirely destroy the insoluble gossypol produced a feed which when properly supplemented afforded good growth and reproduction. These results although perhaps not directly applicable, have an important bearing upon the feeding value and methods of preparation of cottonseed meal for all types of animals. In conclusion the author makes grateful acknowledgment to Dr. V. G. Heller and Dr. N. B. Guerrant for their constant interest and aid during the progress of these investigations with cottonseed meal.