Effects of Di-(2-Ethylhexyl) Phthalate (DEHP) on Gamete Quality Parameters of Male Koi Carp (Cyprinus carpio)

In this study, we evaluated gamete quality parameters ofmaturemale koi carp (Cyprinus carpio) exposed to three different concentrations (1, 10, and 100 mu g/L) of di-(2-ethylhexyl) phthalate (DEHP). After 60 days of exposure, there was a significant decrease in the gonadosomatic index (GSI) of males exposed to 10 and 100 mu g/L of DEHP. Histological analysis of the testes revealed impaired histoarchitecture, including inflammatory cells, intratubular vacuoles, and swollen seminiferous tubules in treatment groups. Gamete quality parameters like sperm production, motility, spermatocrit, and sperm density values were significantly decreased at the 10 and 100 mu g/L concentrations. Biochemical compositions, including glucose, cholesterol, and total protein levels, were significantly changed in the treatment groups. Similarly, the ionic compositions of seminal fluid (Na, K, Ca, and Mg) also varied in the treatment groups. Furthermore, the 11-ketotestosterone levels were decreased, and the 17- fi estradiol levels were increased in the DEHP-treated groups. The mRNA expression levels of reproduction-related genes, including Fshr, Lhr, Ar, Er ff, and Er fi, were significantly changed in the DEHP-treated males in a dose-dependent manner. In conclusion, the findings of this study confirmed that environmentally relevant exposure to DEHP may contribute to a decline in the gamete quality of male fishes.

Automated summary

In this study, the effects of di-(2-ethylhexyl) phthalate (DEHP) exposure on gamete quality of male koi carp were investigated. The results showed that exposure to DEHP led to a decrease in gonadosomatic index, impaired histoarchitecture of the testes, and changes in gamete quality parameters, biochemical compositions, ionic compositions of seminal fluid, and hormone levels. Additionally, the expression levels of reproduction-related genes were also altered in a dose-dependent manner. These findings suggest that environmentally relevant DEHP exposure can have detrimental effects on the gamete quality of male fishes.