<div>Background: Secretions from the seminal vesicular gland enhance the survival and reproductive functions of the spermatozoa. The order Chiroptera has evolved great diversity in their reproductive structure influenced by location, abiotic factors and availability of food. Eidolon helvum is a near threatened tropical African fruit bat and little is known of its reproductive biology. The aim of this study was to highlight the structure, histochemistry and ultrastructure of the seminal vesicular glands of Eidolon helvum.&nbsp; 
 
Methods: The paired seminal vesicular glands of 16 adult male Eidolon helvum were obtained in May during the early rainy season in tropical Nigeria. The glands were evaluated grossly, histological and ultrastructurally. 
 
Result: The spirally coiled tubular organs were divided into numerous lobules of tubular-alveolar glandular acini lined by simple cuboidal epithelium made up of basal cells and mono or bi-nucleated cuboidal secretory cells. PAS positive secretions projected from the apical surfaces. Principal secretory cells contained numerous rough endoplasmic reticulum, mitochondria, Golgi complexes, electron lucid secretory vesicles, electron dense granules and lysosomes. The unique merocrine and apocrine secretions contributed to the formation of vaginal plugs.</div>

Light and Electron Microscopic Studies of the Seminal Vesicular Glands of the African Straw-coloured Fruit Bat, Eidolon helvum