Effect of Castration and Exogenous Testosterone Administration on Physio-biochemical Parameters and Male Accessory Sex Glands of Black Bengal Goat

Abstract

Testosterone, the principal androgen, exerts both androgenic effects involving growth stimulation and functional maintenance of the male reproductive tract and anabolic effects involving growth stimulation of non-reproductive organs and also affects the hemogram of animals. The study was conducted to uncover the effect of castration and administration of exogenous testosterone on physio-biochemical parameters and male accessory sex glands of Black Bengal goat. Fifteen male goats (4 months old) were divided into three groups; Group-A: Goats (castrated), Group-B: Control group and Group-C: Goats with excess testosterone (exogenous IM administration of testosterone enanthate, TE @ 125 mg/goat weekly for a period of 2 months). Castration caused a significant decrease in red blood corpuscles (RBC), packed cell volume (PCV) and percentage of lymphocytes accompanied with significantly increased mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and percentage of neutrophils compared with control group. Treatment with TE caused a significant increase in RBC, PCV and a significant decrease in total number of leucocytes and percentage of neutrophils. The study showed a significant increase in the levels of total cholesterol (TC), triglycerides (TG) and low density lipoprotein (LDL) in castrated group compared with control value. Administration of TE significantly decreased in the levels of TG and LDL compared with control group. A significant decline was observed in total protein, albumin and glucose level in castrated goats. The study showed no significant differences between groups in mean corpuscular hemoglobin concentration (MCHC), high density lipoproteins (HDL), globulin and serum enzyme (SGOT & SGPT) level. There was a significant difference on the length, width and weight of seminal vesicles and bulbourethral glands among three groups of goats indicated that the developmental dependence of the reproductive accessory glands on testosterone. The secretory units of the vesicular glands of all groups were lined by pseudostratified columnar epithelium consisted of tall columnar type cells and short basal type cells. The vesicular secretion was stored in the lumen of secretory units. It was also found the myoepithelial cells around the secretory cells of glandular end pieces of seminal vesicle in all groups of goats that helped in the excretion of vesicular secretion. The thickness of lamina muscularis and adventitia of seminal vesicle decreased gradually and the length and width of glandular secretory unit in propria-submucosa of seminal vesicle increased gradually along with the increment of the level of testosterone. All goats of present study had only pars disseminata (internal portion) and located in the propria-submucosa of the dorsal wall of pelvic urethra. The parenchyma comprised of secretory end pieces and ducts. The secretory units and intraglandular ducts of the prostate gland were lined by simple cuboidal to columnar epithelium with occasional basal cells. The length and width of lobes of prostate glands were significantly decreased in castrated goats and significantly increased in testosterone treated goats. The length and width of secretory units of prostate glands were reduced markedly in castrated goats. The bulbourethral glands (BG) were surrounded by the bulbocavernous muscle and the secretory units were lined with a tall simple columnar epithelium and occasional basal cells. Most of the columnar cells were of the mucous type, with the nuclei basally placed and the cytoplasm contained the secretion granules in all groups. The thickness of capsule of BG of TE treated goats reduced significantly. It can be concluded that castration and exogenous administration of testosterone in goats affect significantly in certain blood constituents and lipid & protein profile. The present findings also provide clear evidence of influence of castration and exogenous testosterone administration on the development of male accessory sex glands in the postnatal life of Black Bengal goat.