Impact of external factors on sperm motility of Sepiella maindroni

Sperm motility is important in reproductive biology. To understand the physiological ecology characteristics of sperm of Sepiella maindroni, we studied the activation rate, active time, and lifespan of sperm to evaluate the influence of external factors, including temperature, salinity, pH, glucose, NaCl, KCl, MgCl2, CaCl2, EDTA-2Na and artificial seawater on sperm motility. The results show that the appropriate activation and motility condition for sperm were： temperature 20-30℃ （optimum 25℃）, salinity 10.6-30.6 （optimum 15.9） and pH 8.0-8.6 （optimum 8.0-8.4）. Sperm activity varied in different concentrations of glucose, NaCl, KCl, MgCl2 and CaCl〉 None of the selected concentrations of EDTA-2Na solution could activate the sperm. The activation rate in artificial seawater devoid of Ca2＋, Mg2＋ or HCO3- was low. The results should help further studies on the preservation and activation of squid sperm.