Use of cottonseed oil-meal in poultry feeding. II. Effects of gossypol on the reproductive parameters

Abstract

Three experiments were carried out to determine the effects of gossypol, administred via the diet, on the reproductive performances of adult cocks and hens of egg-laying or broiler strains. A total of 650 g gossypol acetate were extracted from 80 kg cotton soapstock and cristallised. The product obtained included 47.86 % free gossypol and 61.19 % total gossypol. Balanced diets without cottonseed oil-meal were supplemented with increasing amounts of free gossypol (0, 250, 400, 800 ppm) and offered to breeding cocks and hens. The first trial was made with adult hens and cocks (128 and 45, respectively).It did not show any effect of using dietary gossypol amounts lower or equal to 400 ppm on feed intake, egg-laying, semen production and motility, fertility and hatchability of incubated eggs. The two following trials were performed to determine the effect of 800 ppm of dietary free gossypol on the performances of ten 82-week old breeding cocks of the broiler strain subjected to feed restriction and on twelve 29-week old breeding cocks of the laying strain fed ad libitum This amount of free gossypol (about 20 mg/kg liveweight/day) reduced the feed intake and liveweight of the animals as well as the testicle weight of cocks of the laying strain and it increased the proportion of abnormal spermatozoa in the ejaculates of cocks of the broiler strain. In addition, the liver of cocks fed gossypol supplemented diets exhibited an abnormal brown-green colour. However, on account of the low gossypol concentrations of cottonseed oil-meal (< 250 ppm), the free gossypol contained in this meal is most likely not responsible for the reproductive disorders observed in poultry fed with this kind of feed.