In Vitro Storage of Ova of Persian Sturgeon, Acipenser persicus in Ovarian Fluid: the Changes in the pH and Osmolality of the Ovarian Fluid, Fertilization and Hatching Rates

The unfertilized ova of Persian sturgeon, Acipencer persicus, were stored in the ovarian fluid at 18 C and fertilized after 0 (control), 3, 6, 9 and 12 hours post stripping using fresh and N pooled sperm obtained from three males. In addition, changes in the osmolality and pH of ovarian fluid during storage were recorded. After 3 h of storage, no significant differences were found between fertilization and hatching rates in comparison with control. But, after 6h, 9h and 12 h of storage, fertilization and hatching rates significantly decreased in comparison with control. After 3 h and 6 h of storage, no significant differences were found between values of osmolality of ovarian fluid compared to control. But, after 9 h and 12 h of storage values of osmolality increased significantly compared to control. Also, significant negative correlations were found between osmolality of ovarian fluid and fertilization and hatching rates. The value of pH of ovarian fluid significantly decreased after 6 h of storage compared to control. This decline in the values of pH continued towards the end of the experiment. Also, significant positive correlations were found between pH of ovarian fluid and fertilization and hatching rates. Results showed that the ovulated eggs of Persian sturgeon can be held in ovarian fluid at 18 C up to 3 hours without significant loss of hatchability and fertilization rate. N As well as, the decline of pH and increase of osmolality of ovarian fluid may be two limiting factors for short term storage of ova of Persian sturgeon.