Effect of different concentrations of Tribulus terrestris dry extract on histological structure of gonads and kidneys in Japanese quail.

This experiment was designed to evaluate the effect of different doses of Bulgarian product Vemoherb-T (dry extract of Tribulus terrestris) on egg production, serum level of testosterone and histological structure of gonads and kidneys in Japanese quail. In the experiment a total of 52 female and 16 male Japanese quail from Pharaon breed at the initial age of 44 days were involved. Quails were randomly divided in control and three experimental groups, 13 female and 4 male in each. Experimental groups received with the drink water the tested product in following daily doses: 4 mg/kg body weight (10 weeks); 10 mg/kg body weight (the first 5 weeks of the trial); 10 mg/kg body weight (10 weeks) for I st , II nd , III rd treated groups respectively. A significant increase of ovary weight in quails from III rd experimental group (P < 0.01) in comparison with the control was measured. Egg production in II nd and III rd treated groups increased significantly (P < 0.01) than the control group. Testosterone level of males from III rd experimental group enhanced significantly (P < 0.05; P < 0.01) than other groups. The ovary core part of females from III rd experimental group contained a much lower number of mature follicles in comparison to the other groups and its central medulla was highly vascularized. Tribulus terrestris extract in a dose of 10 mg/kg stimulates the production of male reproductive cells, while the dose of 4 mg/kg caused a delay of spermatozoa production. Histological analysis showed that in all experimental groups the structure of the kidneys was preserved and that the higher doses lead to certain reduction of the parenchyma.