The present work evaluated the effects of feeding graded levels of whole cottonseed on reproductive parameters of Red Sokoto bucks. Twenty Red Sokoto bucks were used for the experiment. After a 14-day pre-treatment period, bucks were assigned for 90 days to one of four isonitrogeneous treatments: control (diet A); 0 mg kg-1 of total gossypol, (diet B); 15% mg kg-1 of total gossypol, (diet C); 30% mg kg-1 of total gossypol and (diet D); 45% mg kg-1 of total gossypol. The mean percentage sperm gross motility was significantly (p < 0.05) lower in group D (45% WCS) compared to groups C (30% WCS) and A (control) at days 60, 75 and 90. The mean semen pH and reaction time were not significantly (p > 0.05) different among treatment groups. Semen colour of the bucks in the control group was majorly creamy, in group C (30% WCS) and B (15% WCS) creamy to milky and group D (45% WCS) colourless. The mean semen volume was significantly (p < 0.05) higher in groups C and A compared to group D (45% WCS) at days 60, 75 and 90. The mean semen concentration was significantly (p < 0.05) lower in group D (45% WCS) when compared to group A (control) at days 30, 45, 60, 75 and 90. Group A (control) bucks had significantly (p < 0.05) higher percentage live sperm compared to those in group D (45% WCS) at days 45, 60, 75 and 90. Mean Sperm morphological abnormalities including detached head, free tail curved tail and midpiece droplets were significantly (p < 0.05) higher in group D (45%) than in group A (Control) at day 15 (for free tails) and day 90 (for all). Testicular and epididymal sperm reserves were higher in animals supplemented with up to 30% whole cottonseed. In conclusion, feeding bucks above 30% WCS resulted in more deleterious effects on the semen characteristics and testicular profile.

The age at puberty of Nigerian dogs around the Federal Capital Territory (FCT), Abuja was determined in order to validate earlier reports from other parts of Nigeria and to provide additional information for canine reproductive research. 16 pre-pubertal female dogs were purchased from different dog markets and households within the FCT. They were housed in cages in groups of four and allowed to acclimatise for two weeks, during which time they were treated against external and internal parasitic infections until they were clinically free from disease. They were also vaccinated against common diseases such as rabies, distemper, leptospirosis, parvo and hepatitis using standard vaccines and fed twice daily with household meals. They were then observed daily for the onset of puberty through behavioural changes, haematology and vaginal cytology. All the dogs attained puberty between eight and thirteen months of age. Dog owners are therefore advised to be properly guided to prepare for the bloody discharge that is associated with onset of reproductive cyclicity. There is also need for patience as many dogs in this environment attain puberty at a later age than exotic breeds.

No abstract

An investigation into the pathological effects of Cypermethrin on the thyroid gland of Yankasa rams was carried out. Sixteen sexually-mature, healthy Yankasa rams aged 18 -30 months and weighing between 21.5 -46.5kg with clinically normal genitalia were used. They were divided equally into two groups (A and B). A served as the treatment group while B served as the control. (A) were given Cypermethrin (3%) at the dose rate of 3mg/kg (0.1ml/kg) body weight, topically as pouron. (B)were given distilled water at the same dose rate of 0.1ml/kg body weight topically as pour-on. These treatments were repeated every two weeks for a period of 12 weeks. The rams were sacrificed at the end of 12 weeks and the following organs (liver, heart, kidney, brain and thyroid gland), were collected for gross and histopathology. Results showed that no gross pathologic lesions were found on the thyroid gland, theliver, brain and the kidneys of both groups. The heart of the treated group showed petechial hemorrhage. The mean weights of the following organs; liver, thyroid gland, kidneys and heart of the treated and the control groups were 400.00±0.00g and 420.00±20.0g; 2.30±0.37g and 1.50±0.31g; 70.20±9.90g and 72.60±3.70;127.51±46 and 100.00±20.00respectively. The differences in weight between the two groups were not significantly different (P>0.05). Histologic sections of the thyroid glands of the treated group showed hyperplasia of the follicular epithelial cells followed by collapsing of the follicles. Histologic sections of the cardiac muscles of the treated group showed focal infiltration of lymphocytes and loss of striations (degeneration). The liver, the kidneysand thebrain (cerebrum) of both groups showed no histologic lesions. It was concluded that Cypermethrin induced thyroid and cardiac pathology in the rams. It was recommended that more investigation be done to unravel the mechanism of inducing thyroid and cardiac pathology in rams.

This work was designed to make further observations on the specific types of sperm abnormalities present in Cypermethrin treated rams and contribute information towards understanding how Cypermethrin affects male's reproduction. Sixteen sexually-mature, healthy Yankasa rams aged 18 to 30 months and weighing between 21.5 to 46.5 kg were used. The 16 rams were divided equally into two groups (A and B). Group A served as the treatment group, while B served as the control. The rams in Group A were given Cypermethrin (3%) at the dose rate of 3 mg/kg (0.1 ml/kg) body weight, topically as pour-on. The control rams were given distilled water at the same dose rate and route. These treatments were repeated every two weeks for a period of 12 weeks. Semen was collected on weekly basis from each ram during the experimental period by means of a hand held electro-ejaculator (EE). The morphological sperm abnormalities/defects were determined by examining semen smears stained with eosin-nigrosin on a glass slide. Results showed that sperm abnormalities recorded were detached head, mid piece droplet, free tail, coiled tail and bent tail. There was no significant difference in the percentage of these abnormalities recorded between the two groups (p>0.05) from week 1 to 12. It is concluded that Cypermethrin did not induce any specific sperm abnormalities in rams treated with 3 mg/kg body weight as pour-on. Sperm death in Cypermethrin label dose treated rams may be mediated through oxidative stress. It was recommended that more studies be directed towards stress biomarkers in Cypermethrin treated rams.