Spermiation time affect the milt quality indices of the Russian sturgeon, Acipenser gueldenstaedtii, Brandt & Ratzeburg, 1833

摘要

In this study, the effects of spermiation time are investigated on milt quality of Russian sturgeon over the course of the spawning season. The milt samples were collected from three broodstock batches at three time points including: the beginning, middle and at the end of the spawning season. According to the results, the milt quality parameters including pH, sperm density, spermatocrit, duration of sperm motility and percentage of sperm motility were significantly low in the beginning and end of season than middle of season. The values of milt quality parameters in the middle of season were as follows: (motility percentage: 69.6 +/- 3.5, motility duration: 460.3 +/- 37.2 s, sperm density: 8.7 +/- 0.4 x 10(9), milt volume: 86.3 +/- 8.1 and milt pH: 8.3 +/- 0.15). Significant positive correlations were also found between milt pH and sperm motility as well as between sperm density and spermatocrit. In conclusion, our study showed that the middle of season is the best time for collection of milt with appropriate quality in Russian sturgeon. Selection of milt with good quality is necessary aim to cryopreservation of spermatozoa in endangered fish species including Russian sturgeon.