Histological, Histochemical and Immunohistochemical Characterization of the Testis of Double-Spurred Francolin (Francolinus Bicalcaratus) in A Reproductive Cycle

The Double-spurred Francolin (Francolinus bicalcaratus) is a feral bird and remains undomesticated with very little known about its reproductive capability, hence, this study was carried out to know about the structural integrity of its testis. Birds (n=5), were obtained during the dry and rainy seasons from their natural habitat in Kano, stabilized and acclimatized for two weeks in the Experimental Animal House of the Veterinary Anatomy Department, University of Ibadan. The Birds were weighed, sedated and sacrificed by decapitation. The testis was removed and fixed in neutral buffered formalin and then processed histochemically for Reticulin fibres using Gordon and Sweet’s stain and Collagen fibres using Verhoff-Van Gieson stain. Paraffin-embedded sections of each fixed testes were cut and stained with Haematoxylin and Eosin, then immunostained for structural proteins with monoclonal antibodies against Vimentin, Desmin, Pancytokeratin and Alpha smooth muscle Actin. Results indicate that the mean morphometric values for testis and epididymis observed were highest at late rainy season and lowest at early dry season for all indexes except for the testicular capsule thickness that was lowest at late rainy season and highest at late dry season. The testicular capsule and peritubular layer immunostained for alpha smooth muscle actin, desmin, pancytokeratin and vimentin and were thickest at late rainy season. The capsule was histochemically positive for collagen fibres mostly restricted to the tunica Albuginea. We also, observed that the peritubular wall was positive for reticulin, thickest at late dry season. We therefore, conclude that capsular and peritubular tissues of the testis are similar to that of Muscuvy duck, quail and domestic fowl. The testicular capsule is rich in collagen and would be actively involved in keeping the testis from total collapse when it regresses at late dry season.

Key Words: Histology, Histochemistry, immunohistochemistry, Testis, Morphometrics Francolinus bicalcaratus