The dependence of the duration of sperm motility in Ob–Irtysh basin coregonidae on temperature

Abstract

The duration of sperm motility in four whitefish species in the Ob–Irtysh basin, namely, Coregonus tugun, the river and lake forms of C. peled, C. lavaretus pidschian, and C. nasus, has been studied. It is shown that the duration of sperm motility in these species has a statistically significant inversely proportional dependence on the temperature of the water that is used for activation. The total duration of sperm motility at the spawning temperature in the range from 0.1 to 5.0°C amounts to 331 ± 107 s, on average, while the duration of forward movement amounts to 149 ± 44 s, on average. At temperatures that exceed the spawning values (above 7.1°C), these parameters constitute 190 ± 47 and 86 ± 15 s, respectively. The highest interspecific variability in the duration of sperm motility was observed within the temperature range from 0.1 to 2.5 and above 7.1°C. C. tugun shows less dependence of the duration of sperm motility on temperature than the other species under study. At a temperature of 0.7°C, the total duration and duration of the forward movement of C. tugun sperm are 201 and 108 s, respectively. When the temperature was increased to 13.4°C, these parameters decreased by 1.2 and 1.1 times only, i.e., to 172 and 100 s, respectively.