0.05) between the rainy and dry seasons in the basement membrane of the testes, seminiferous tubular diameter, and round spermatid nuclear diameter. There were also similarities (p>0.05) between the seasons in epididymal luminal diameters, epididymal epithelial heights as well as in Leydig/sertoli cell ratio and sertoli cell Índex. Quadratic regression analyses showed that all the histometric characteristics of the testes are highly predictable from the live weights of the animals. It is concluded from these results that the WAD goat would not have a restricted breeding season in it native tropical environment. Young sires could therefore be selected early in life for planned improvement programmes in research institutions and breeding centers thus providing farmers with quicker returns for their investments.]]>

Effects of vitamin E and Selenium administration on fertility and lamb performance of Yankasa sheep were evaluated. Thirty post pubertal ewes (1-1 1/2 years of age) and nine rams (2-2 1/2 years of age) were used for the study. The ewes were randomly assigned into 3 groups (n = 10). Animals in group 1 served as control and were administered 1 ml normal saline. Animals in group 2 were administered 90 mg Tocopherol acetate (Vitamin E), while group 3 received injection containing a combination of 100 mg tocopherol acetate and 1.97 mg sodium selenite. Two doses of the injections were administered 14 days apart (subcutaneously). Estrus was synchronized in the ewes using controlled internal drug release device (CIDR). Rams were used for estrus detection and mating starting 24 hours following withdrawal of CIDR. Ewes were allowed to carry the pregnancy to term. The results indicate higher (p < 0.05) estrus response (80.00, 100.00, 100.00), pregnancy rate (75.00, 100.00, 100.00) and lambing rate (66.6, 100.00, 100.00) in ewes following administration of vitamin E and a combination of vitamin E and selenium. Average daily weight gain of lambs was also significantly enhanced (p < 0.05) by treatment. It can be concluded that administration of Vitamin E alone and in combination with selenium resulted in improved reproductive performance on Yankasa sheep.

The effects of season on the morphometric characteristics of the reproductive organs of the pubertal West African Dwarf buck in its native humid tropical environment were investigated. All morphometric characteristics as well as the derivations from both testicular and epididymal morphometry were unaffected by season (p<0.05). There were however, highly significant correlations (p<0.05, p<0.01, p<0.001) between body weight and testicular as well as epididymal morphometry. The results also showed that both testicular and epididymal morphometric characteristics in the pubertal buck are highly predictable from body weight and as such lend ground for the early selection of good sires from records of their growth rate. The non effect of season on both testicular and epididymal morphometry in this work generally demonstrates that there might be no restricted breeding season for the West African dwarf buck in its native humid tropical environment.

ABSTRACT16 female grower rabbits were randomly assigned to any of 4 isonitrogeneous and iso-caloric diets containing 0%, 10%, 20% and 30% pawpaw meal (PPM)

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