Can artificial reproduction strategies (hormonal type and dose/thermal regime) affect gamete quality in indoor-reared pikeperch (Sander lucioperca)?

Abstract

The present study aimed at evaluating the effects of different thermal regimes and synthetic hormones on sperm quality as well two (low vs. high) salmon gonadoliberin (sGnRHa) dosages on egg quality in indoor-reared pikeperch. Two groups of females were formed receiving either 5 µg kg−1 or 50 µg kg−1 of sGnRHa. Likewise, four groups of males were formed that were hormonally treated at either 5 °C or 9 °C, and each temperature receiving either 25 µg kg−1 of sGnRHa or 10 µg kg−1 recombinant human chorionic gonadotropin (hCGrec). Each group consisted of five specimens. Low dosage of sGnRHa showed lower survival of embryos (17.4 ± 29.1% vs. 50.3 ± 7.3%), while there were no differences in sperm quality parameters among the male groups. Overall, best male performance was seen in the group injected with sGnRHa at 9 °C, having the greatest values for all but one of the evaluated parameters. A higher dosage of 50 µg kg−1 can be supported as optimal for a stable thermal regime in pikeperch artificial reproduction, while the differences in the physiological state of breeders under the different thermal regimes should be of interest in future studies. No differences in assessed sperm quality parameters indicate that males are tolerant to thermal manipulations while synthetic form of gonadotropin is applicable for pikeperch propagation and should be evaluated in a more comprehensive study.

Keywords

• Synthetic hormones
• Artificial reproduction
• Sperm quality
• Egg quality
• Thermal regime