Dose-dependent Effect of Garlic (Allium Sativum) Extract feeding on Semen Characteristics and Testes in Wistar Rats

Abstract

Allium sativum (garlic) is widely used all over the world for the prevention and treatment of several diseases. However, the dose-dependent effect of garlic on the male reproductive system in apparently healthy subjects has not been sufficiently evaluated. The objective of the study was to determine the dose-dependent impact of aqueous extract of garlic on semen characteristics and testicular morphology in male Wistar rats. Twenty adult male Wistar rats were assigned into four groups of five rats in each group.. Group 1 (control) was given feed and water only, group 2 was given 500mg/kg body weight (BW) of Allium sativum extract, group 3 was given 750mg/kg BW of Allium sativum extract and group 4 received 1000mg/kg BW of Allium sativum extract. All groups were given feed and water ad libitum. The experiment lasted for 30 days after which the animals were sacrificed; the testis and epididymis were collected for laboratory analysis. The epididymis was homogenized in buffer, diluted, and analyzed microscopically. The data generated were compared using analysis of variance (ANOVA). Data showed that the administration of high concentrations of garlic caused teratozoospermia characterized by a poorly formed head, tailless sperm cells, and bent body with premature sperm cells. Histological findings also showed mild distortions in the shape of seminiferous tubules, congestions in interstitial blood vessels (suggestive of inflammation), slight reductions in size, and mildly thickened outlines of seminiferous tubules. Sperm progressive motility was significantly higher in the high dose group while no significant difference was observed in sperm count, morphology, viability, and pH. The consumption of high concentrations of  Allium sativum may lead to adverse consequences on teratozoospermia and inflammation of the interstitial blood vessels in Wistar rats. Therefore, raw garlic should be consumed with caution as high concentrations may be deleterious to male reproductive health.