Effect of Physical Factors on Milt Quality of Malabar Grouper, Epinephelus Malabaricus in Summer and Winter Season

A study was conducted to test the effect of physical factors such as temperature, salinity, and pH on spermatozoa motility of Malabar grouper (Epinephelus malabaricus). Mature and healthy male fishes were collected from the Red Sea during the summer and winter seasons for milt collection. Milt quality was assessed for colour, volume, sperm cell concentration, motility, and viability. Sperm motility was tested under different water temperatures, salinity, and pH media. A significant difference (P < 0.01) in sperm cell concentration (density), sperm motility (%), and viability (%) was observed between the summer and winter seasons. Changes in water temperature, pH, and salinity influenced sperm motility (%) and motility duration (min). Low pH and salinity caused adverse effects on spermatozoa motility. The results of the study are useful for the germplasm conservation of Malabar grouper, E.malabaricus.