بررسي كيفيت شهب مولدين ماهي آزاد درياي خزر (Salm trutta caspius) صيد شده از رودخانه هاي سرد آبرود و تنكابن طي فصل تخمريزي

Investigation of milt quality of captured Caspian brown trout, (Salmo trutta caspius) brooders from Sardabrud and Tonekabon rivers during the spawning season

To evaluate the ability of Caspian brown trout males (Salmo trutta caspius,) in production of semen with desirable quality, the quality characteristics of semen including: sperm production (semen volume, sperm density and spermatocrit), sperm motility characteristics (percentage and duration of motility) and semen pH were investigated during the sequential strippings in the spawning season. In this regard, the tagged males were stripped four times during the spawning season. According to the data, the values of semen volume, sperm density and spermatocrit showed a significant decrease towards the end of the season (p<0.05). The semen pH, the duration and percentage of sperm were comparatively stable (p>0.05) and only a significant decrease was recorded for these parameters at the end of the season (p<0.05). As well as, significant positive relationships were found for semen volume vs. sperm density (p<0.0001); semen volume vs. spermatocrit (p<0.0001); spermatocrit vs. sperm density (p<0.0001); the pH of semen vs. the duration of motility (p<0.0001). Key words: semen, sperm density, spermatocrit, sperm motility, Caspian brown trout