Semen Quality of Threatened Native Population of Mediterranean Brown Trout (Salmo cettii, Rafinesque 1810) in the Biferno River (Molise Region - South Italy)

This research aimed to provide a characterization of fresh semen in wild and threatened Mediterranean brown trout (Salmo cettii), inhabiting the Biferno River basin and to study the variance of sperm parameters in a reproductive system with high male competition. The evaluated sperm quality parameters were: volume, density, viability, motility and sperm movement duration. High variability in sperm traits were found probably in response to the heterogeneity of individual condition, social status, spawning activity and migration costs. Duration of motility was positively correlated (P<0.05) with age class of breeders and motility. Stronger positive correlations (P<0.001) were observed between motility and viability and between sperm counts and viable sperms. This study reported the first data about semen quality of an Italian wild population of native trout. These results are useful for planning efficient artificial fertilization protocols in restoration programs involving supportive breeding together with other innovative conservation strategies as gamete cryopreservation.