Analysis of Prussian carp (Carassius gibelio B.) oocytes under the influence of Roundup® herbicide.

The aim of this study was to investigate the effect of Roundup^® herbicide on the maturation of Prussian carp oocytes under laboratory conditions. The Prussian carp is currently one of the most common fish species in Polish freshwater ichthyofauna. For the investigation, oocytes from five sexually mature female Prussian carp were used, segmented into three groups, and incubated for 24 h in Cortland's saline, treated with varied concentrations of the herbicide Roundup^® (0 ng - control, R1 - 10 ng/ml, and R2 - 100 ng/ml). Subsequent to this period, assays were performed using the prepared plates to determine the level of 17α,20β-dihydroxyprogesterone (17α,20β-P) utilizing the standard ELISA technique. In determining the 17α,20β-P via ELISA, the medium was extracted from each tested oocyte group. Oocyte maturity was assessed through preservation in serra fluid, and, to categorize the maturity stage of the oocytes utilizing a four-point scale - contingent upon the nucleus's position - the formerly preserved oocytes were dehydrated and subsequently analyzed. A contrast was noted in the percentage of oocytes at varied stages between the control group and the experimental groups. Specifically, a higher concentration of Roundup^® (100 ng/ml) accelerated to expedite the initial migration of the nucleus in oocytes. In conclusion, the obtained results show the adverse effect of Roundup^® on hormonal regulation and maturation in Prussian carp oocytes.