Vol. 9, Issue 12, Part C (2025)

The present investigation dealt with seasonal variation in distribution of histochemical moieties in stray dog testis (Canis familiaris). The study was conducted on the testes of 18 adult, healthy dogs captured and operated for sterilization at the Veterinary Hospital of Junagadh Municipal Corporation, Ivanagar, Junagadh. Histochemical observations were recorded on the H & E-stained section of the testis of the dog, using Carl Zeiss Zen (Blue edition) microscopic image analysis software. The samples were examined under a light microscope using x100 and then x400 magnification. Presence of neutral mucopolysaccharides, acid mucopolysaccharides, protein, lipids and cholesterol were demonstrated by Periodic Acid Schiff, Alcian Blue, Mercury bromophenol blue, Oil red O stain and Schultz method, respectively. Capsule, trabeculae, basement membrane of seminiferous tubules, interstitial connective tissue and mediastinum revealed an intense positive reaction for PAS in all three seasons. The cytoplasm of Leydig cells showed weak to moderate positive reaction for PAS in summer, while a moderate reaction was observed in the monsoon and winter. Spermatogonia and primary spermatocytes showed a weak reaction in the summer and winter seasons. Whereas, in the monsoon season, the reaction was weak to moderate for PAS. Secondary spermatocytes, spermatids and spermatozoa showed a moderate PAS-positive reaction in monsoon and winter. Weak to moderate reactions for Alcian Blue in all three seasons were observed for the basement membrane of seminiferous tubules. Interstitial connective tissue showed weak to moderate affinity for Alcian Blue in summer and winter, while, during the monsoon, the reaction was moderate. The cytoplasm of Leydig cells was moderately positive in the summer and weak to moderately positive during the monsoon and winter for Alcian Blue. Mercury bromophenol blue positive reaction was observed throughout the testis of dog, indicating the presence of basic protein in the structure of the testis. The concentration of protein was higher in the monsoon and winter seasons as compared to summer. A high protein content was observed in the secondary spermatocytes, spermatids, spermatozoa and Leydig cells during the monsoon and winter seasons in the testes of dog. The content of lipid indicated by moderate reaction to Oil red O and Sudan Black B stains was observed in interstitial tissue and with Oil red O small granules with positive reaction were observed in the seminiferous tubules during the monsoon and winter. The moderate amount of cholesterol was observed in the interstitial tissue during the summer season, as demonstrated by the Schultz technique.