Determination of some seminal plasma indices, sperm density and sperm motility in the Persian sturgeon Acipenser persicus

Some biological aspects of semen were investigated in the Persian sturgeon, Acipenser persicus, by determination of seminal plasma indices (ionic composition and osmolality), sperm density and their relationships with sperm motility. The osmolality of seminal plasma ranged from ۴۲.۰۰ to ۱۱۱.۰۰ mOsmol Kg-۱. The concentrations of Sodium (Na+), Potassium (K+), Chloride (Cl-), Calcium (Ca۲+) and Magnesium (Mg۲+) ions were ۶۲.۴۴±۶.۸۲, ۶.۹۲±۰.۸۸, ۲۱.۱۱±۵.۴۱, ۰.۷۹± ۰.۰۳ and ۰.۵۲±۰.۰۳mM L-۱, respectively. The sperm density was ۸.۳۴±۱.۳۸×۱۰۹ spz/ml.  The Sodium/Potassium and Calcium/Potassium ratios were ۹.۰۲ and ۰.۱۳, respectively. The following significant positive correlations were found between seminal plasma indices; osmolality - Cl- (r۲= ۰.۴۹۲, P<۰.۰۵), osmolality - Na+ (r۲= ۰.۹۰۵, P<۰.۰۰۱) and Na+ - Cl- (r۲= ۰.۵۸۴, P<۰.۰۵). There were also no significant correlations between ionic composition and osmolality of the seminal plasma and sperm motility (P>۰.۰۵).  No relationship was observed between sperm density and its motility at the concentrations tested (r۲= ۰.۰۱۵, P>۰.۰۵). The ionic composition and osmolality of seminal plasma reveals an inter-species specific as well high secretory activity of sperm duct. The clear differences observed in A. persicus should be considered when cryopreservation methods for sperm are developed in Acipenseridae species. 

Keywords:

Acipenser persicus , Ionic content , Osmolality , Seminal , Plasma , Sperm density , Sperm motility