en Genetics Genetics پژوهشي Orginal research papers A study on motility of spermatozoa of the Persian sturgeon, <em>Acipenser persicus</em> were carried out. The time of relative cessation of sperm activity was evaluated using microscopic observation. Sperm was activated with three different swimming medium, freshwater pH 7.5, and two different buffered saline solutions, pH 7.5. Total period of the motility of <em>A. persicus</em> spermatozoa was shorter in freshwater than saline solutions. Significant correlation was found between period of sperm motility and dilution rate. Increasing dilution rate from 1:50 to 1:500 had negative effect on sperm motility and significantly decreased the duration of motility (P<0.01). There was also significant correlation between ionic composition of swimming medium and total period of sperm motility. &nbsp; Acipenser persicus, Spermatozoa, Period of motility, Dilution rate, Freshwater, Saline solution 67 76 http://jifro.ir/browse.php?a_code=A-10-42-2&slc_lang=en&sid=1 S.M. Hadi Alavi smhai_alavi@yahoo.com 100319475328460024490 100319475328460024490 Yes B. Mojazi Amiri 100319475328460024491 100319475328460024491 No M. Pourkazemi 100319475328460024492 100319475328460024492 No