Influence of pH, temperature, salinity and media on activation of motility and short term preservation of spermatozoa of an estuarine fish, Mystus gulio (Hamilton) (Siluridae-Pisces)

Abstract

The effect of various activating media, salinity, pH and temperature on the duration of sperm motility of M.gulio was examined. Among the activating media used (fertilising solution, fresh water, distilled water and 5% glucose solution) fertilising solution was found to be an ideal medium for sperm activation. The activation and duration of spermatozoan motility were maximum in 8.75x10(-3) salinity. Alkaline pH was found to be most conducive to sperm activation and the maximum spermatozoan motility was observed at pH 8. The duration of motility of spermatozoa increased with increase in temperature. The fresh milt of M.gulio can be stored up to seven days at 4 degrees C in the refrigerator without significantly reducing the motility and viability of spermatozoa. The spermatozoan motility was considerably prolonged by storing the semen under oxygen than storage under air. Short term preservation of spermatozoa without adding extender media under oxygen atmosphere was found to be better than semen preservation using extender media.