Sperm quality, egg size, fecundity and their relationships with fertilization rate of grass carp (Ctenopharyngodon idella)
Gametes were collected by abdominal massage from 15 anesthesized male and female grass carp. In collected sperm samples the following mean spermatological properties were determined: sperm volume 15.64 ± 5.39 mL, sperm motility 81.20 ± 7.61%, motility duration 62.06 ± 19.40s, density 17.88±5.48 x109 mL-1, total density 428.90±302.05 x109, and pH 7.25±0.81. Also egg size (mm) and fecundity (egg/fish) were determined as 1.04±0.028 and 417867 ± 36.274 respectively in female grass carp. The fertilization capacity of sperm was tested with the same egg pool. The insemination dosage was 2x105 spz/egg for each fertilization experiment. Fertilization rate was determined as mean 79.3±2.95% and positively correlated with sperm motility (r=0.932, p < 0.01), egg size (r=0.513, p>0.05) and fecundity (r=0.539, p>0.05).