Chronic Toxoplasma gondii infection and its influence on semen analysis in rats: controlled experimental animal study

Infertility is a significant global health concern that has been related to various infectious agents. While Toxoplasma gondii (T. gondii) is a ubiquitous protozoan parasite that affects various body organs, little is known concerning how it may affect the male reproductive system. This research aims to study the impact of T. gondii infection on semen analysis in experimentally infected rats, focusing on the parameters of sperm count, motility, and morphological integrity. This controlled experimental animal study involved 36 outbred male Wistar rats (24 cases and 12 controls). The rats were infected with the ME-49 strain of T. gondii. The rats were euthanized at days 40, 50, and 60 PI, and the testes and epididymides were removed immediately. The body weight testis weight ratio was assessed. Chronic toxoplasmosis was evaluated by examination of the brain for T. gondii cysts. Histopathological examination of the brain and scoring of its lesions were performed. Semen analysis was performed, and sperm parameters were assessed for count, motility, viability and morphological characteristics. The correlations between the sperm parameters and the brain inflammation score and the brain cyst burden were investigated. Cysts of Toxoplasma were found in the brain homogenates of all infected rats. The median percentage of progressively motile sperm, median sperm count, and median percentage of viable sperm in the T. gondii-infected group were significantly lower than those in the control group (P<.05). At all-time points, the percentage of normal sperm in the infected rats was significantly lower than that in the control rats. At all-time points, the T. gondii infected rat group had a considerably greater median proportion of morphologically abnormal sperm than did the control group (P<.05). This study demonstrated that T. gondii infection significantly impacts semen quality in an experimental rat model. Chronic toxoplasmosis is associated with significant reductions in sperm count, motility, and viability and an increase in morphologically abnormal sperm. The demonstrated alterations in semen parameters highlight the potential role of T. gondii as a contributing factor to male rat reduced fertility.