The comparison and improvement of artificial media used for the maturation of testicular sperm of rainbow trout neomales

Abstract

With the aim of helping rainbow trout farmers improve all-female production efficiency, we conducted two consecutive experiments in this study. In the first experiment, we compared the in vitro maturation success of testicular sperm by incubating it at 4 °C in four different artificial media for 30–150 min. Based on the effective results obtained with the modified Cortland medium (MCR) and 120 min incubation period in this experiment, we conducted a second experiment. In the second experiment, we evaluated whether the incorporation of an extra buffer (25 mM hepes) and an antioxidant (10 mg ml?1 bovine serum albumin or 0.5 mM uric acid) into the MCR can further improve the quality of testicular sperm in terms of motility and fertilizing capacity. The results of the second experiment revealed that hepes or bovine serum albumin incorporation into the MCR does not provide substantial improvement, but supplementing these solutions with uric acid could significantly increase the mean motility rate and fertilizing capacity of the incubated sperm. We discussed these results by comparing them with the contents of artificial media in order to elucidate the factors affecting the in vitro maturation success of testicular sperm. We believe that the present study provides new information that is beneficial to trout farmers in order to improve their all-female production efficiency. In addition to this, it might include some valuable new insides for researchers working in the field of sperm physiology. © 2020 Elsevier B.V.