Testing
cryopreserved European eel sperm for hybridization (A. japonica × A. anguilla).
T. Müller, H. Matsubara, Y. Kubara, Á. Horváth, B.
Kolics, J. Taller, V. Stéger, B. Kovács, L. Horváth, J.F. Asturiano, D.S.
Peñaranda, D. Kucharczyk, B. Urbányi
Abstract
The objective of this study was to assess impact of
cryopreserved European eel sperm and Japanese eel native sperm on early
fertilization, hatch, survival, and malformation rates of larvae, as well as
develop molecular techniques to distinguish different eel species. Eggs from
Japanese eel females (Anguilla japonica)
were artificially fertilized with sperm of Japanese eel males and cryopreserved
sperm from European eel (A. anguilla,
extender was modified Tanaka solution and methanol as cryoprotectant). There
were no statistical differences (p>0.05) among the measured parameters such
as fertilization, hatch and survival after 10 days post-hatch rates due to
large individual differences. The malformation rate of larvae compared to the hatching
rate was higher in cryopreserved groups than in the control indicating that the
methodology needs further refinement. Genetic analyses (PCR-RFLP, PCR-HRM)
proved a clear result in the detection of paternal contribution in
hybridization between the Japanese and the European eel and applied PCR-HRM
method is a quick and cost effective tool to identify illegally imported A. anguilla at the glass eel stage,
which can be transported from Europe to Asia.
