P. Koumpiadis, D.E. Sganga, S.N. Politis, V. Gallego, I.A.E. Butts, J.F. Asturiano, I.E. Batjakas, J. Tomkiewicz
Aquaculture production relies on controlled management of gametogenesis, especially in species where assisted reproduction is needed for obtaining high-quality gametes in captivity. The present study used hormonal treatments to induce and sustain spermatogenesis in European eel (Anguilla anguilla), focusing on the effect of strip-spawning timing (12 vs. 24 h) after weekly administration of human chorionic gonadotropin and the necessity of a primer injection (in addition to weekly hormonal treatment), prior to strip-spawning (primer vs. no-primer). Sperm quality parameters included sperm density, assessed by hemocytometer counting and spermatocrit, as well as sperm kinematic (motility and velocity) parameters at three time points after onset of hormonal treatment (Weeks 9, 11, and 13). All males responded to hormonal treatment and spermiation was observed by Week 5. During the experimental timeline from Weeks 9 to 13, milt production and sperm kinetic parameters increased, while sperm density decreased. Variability in sperm kinetic traits was observed depending on strip-spawning timing (12 or 24 h) after hormone injection and the primer treatment did not show a significant effect on sperm quality. Moreover, spermatocrit values and hemocytometer counts were highly correlated. Overall, the hormonal treatment and stripping at two-week intervals provided suited milt production and high-quality sperm. Considering that each male may be stripped 4-5 times over the 2-3 months spawning season, handling and hormone administration can possibly be reduced by eliminating the primer.
Disponible en: http://doi.org/10.1111/rda.14011