Studies on the effects of diets containing gossypol on testes of adult teddy buck

To Study the possible effects of diets containing gossypol on the semen quality and testicular morphology, nine adult teddy bucks were randomly divided into three equal groups named A, B, and C. Bucks in group A were fed control ration `a' (without gossypol). Animals in group B were fed ration `b' which contained unboiled cottonseed cakes (containing both free and bound gossypol contents of 0.62 and 1.75g/kg of ration respectively), and those in group C were given ration `c' containing cottonseed cakes boiled at 100 degree C for one hour (which contained bound gossypol only, at the rate of 2.73 g/kg of ration). Experimental rations were fed to the bucks of respective groups at the rate of 0.88 kg per buck per day. For three months free and bound gossypol feeding of group B were 18.61 and 52.51 mg per kg body weight per day, respectively and amount of bound gossypol fed to the experimental animals of group C was 71.11 mg per kg body weight per day. In addition, bucks in all the three groups were offered good quality chaffed seasonal green fodder and clean water ad libitum. At the end of the treatment period, the right testis of each experimental buck was removed surgically. Biometric parameters of the testes were recorded immediately after their removal. Tissue samples were taken from the proximal, middle and distal parts of the testes, preserved in 10 percent, buffered formal saline solution and processed for histological studies. During the post-operative rest period of one month, experimental animals in all groups in addition to seasonal green fodder were fed ration `a' (without gossypol) on the same rate and pattern as it was fed during treatment period. Experimental animals in each group (A, B and C) were fed with experimental ration `a' (without gossypol), at the rate of 0.88 kg per buck per day in addition to seasonal green fodder for another three months period from mid December to mid March (withdrawal period). During this period, body weight measurements and collection and evaluation of semen were continued on the same pattern as during treatment period. Immediately after the completion of withdrawal period, remaining (left) testis of each buck was removed. Biometric values were recorded and tissue samples were processed for histopathological examination. The data obtained showed that the free and the total gossypol contents of cottonseed cakes averaged 0.28 plus minus 0.02 and 1.44 plus minus 0.02 percent, respectively. The highest values of free and total gossypol, 0.36 plus minus 0.02 and 1.59 plus minus 0.03 percent respectively, were obtained in cottonseed cake samples collected from Vehari district, while the lowest values, 0.21 plus minus 0.01 and 1.29 plus minus 0.01 percent respectively, were found in those collected from Lahore district. Analysis of variance revealed significant differences (P less than 0.05) in the free and the total gossypol contents of cottonseed cakes among various districts. Feeding of unboiled and boiled cottonseed cakes to adult teddy bucks during treatment period did not cause any sign of gossypol toxicity. Moreover, these treatments did not affect the body weight, biometry of testicles, colour, volume, mass activity, sperm concentration, percentage of dead spermatozoa or liveability and absolute index of liveability of spermatozoa at 37 degree C. The feeding of ration containing gossypol did affect the pH percentage of motility of spermatozoa and percentage of morphologically abnormal spermatozoa. The teddy bucks fed rations containing a combination of free and bound gossypol showed an increase in the pH during treatment period and this increase continued even after conclusion of withdrawal period. The percentage of motility of spermatozoa in animals fed a combination of free and bound gossypol decreased over a treatment period of three months and was statistically lower than those fed control diet or diet containing bound gossypol. The feeding of rations containing a combination of free and bound gossypol or bound gossypol only both adversely affected the percentage of morphologically abnormal spermatozoa at the termination of treatment period. Histological examination of the somniferous tubules at the termination of treatment period revealed a significant (P less than 0.05) increase in the total diameter and lumen diameter and a significant (P less than 0.05) decrease in wall thickness of somniferous tubules in bucks fed diet containing unboiled cottonseed cakes compared with those in control group. Feed containing boiled cottonseed cakes did not seem to affect these, parameters significantly (P greater than 0.05). The number of spermatogenic cell layers was also significantly (P less than 0.05) lower in the testis of bucks fed unboiled cottonseed cakes compared with those of controls and non-significantly (P greater than 0.05) lower compared with those fed boiled cottonseed cakes indicating a disruption in spermatogenesis. The Leydig cell diameter, however, was not affected during treatment period. Based on the data, it is conceivable that cottonseed cakes available in different parts of the country differ significantly in their free and total gossypol contents. Rations containing unboiled or boiled CSC adversely affected the semen quality of teddy bucks in terms of sperm motility and morphologically abnormal spermatozoa in the ejaculates. The rations containing unboiled cottonseed cakes adversely affected the wall thickness and number of spermatogenic cell layers in somniferous tubules. Mild testicular degeneration was also observed in teddy bucks after feeding unboiled and boiled cottonseed cakes for a period of three months. The effects of cottonseed cakes (containing both free and bound gossypol) were more severe than those of boiled cottonseed cakes (containing bound gossypol only). The adverse effects of cottonseed cakes on the semen quality and testicular morphology seemed to have been reversed at least partially within four months after cessation of the treatment. The adverse effects of cottonseed cakes on male reproduction function seem to have been reduced by boiling cottonseed cakes at 100 degree C for one hour.