Regulation Of Sperm Motility And Research Of Individual Fecundity In The Rutilus Rutilus Lacustris (Pallas)

Rutilus rutilus lacustris（Pallas）is an indigenous economic fish in Xinjiang.In recent years,under the influence of factors such as water conservancy construction,environmental changes,and overfishing,the population of the R.rutilus lacustris（Pallas）in Ulungur Lake has dropped sharply.In 2019,it was listed as a Class II protected fish in Xinjiang.Therefore,it is necessary to carry out research on the reproductive biology of the R.rutilus lacustris（Pallas）.In this paper,fast movement time（FT）and life time（LT）were selected as indicators,single factor test and orthogonal test were used to study different osmotic pressures of Na⁺solutions,K⁺solutions,glucose solutions,fructose solutions,galactose solutions and different p H solutions on the individual and comprehensive regulation of sperm motility of the R.rutilus lacustris（Pallas）.65 the females wild R.rutilus lacustris（Pallas）in the IV stage of gonadal development were selected as the research objects.Statistical fecundity by gravimetric method,and using regression analysis method,the correlation between the absolute fecundity and relative fecundity of the R.rutilus lacustris（Pallas）and the six biological indicators of body length,body weight,net weight,gonad weight,K and GSI was studied.And which constructed the prediction equation of the individual fecundity of the R.rutilus lacustris（Pallas）.Screening the suitable formula of the sperm activating liquid of R.rutilus lacustris（Pallas）,and to provide a theoretical reference for the selection of parent fish,artificial reproduction,and rational development and scientific protection of the R.rutilus lacustris（Pallas）population resources.The main results are as follows:（1）The single factor regulation test results of different osmotic pressures of Na⁺solutions,K⁺solutions,glucose solutions,fructose solutions,galactose solutions and different p H solutions on sperm motility of the R.rutilus lacustris（Pallas）.The results show:The maximum FT and LT was 40.00±0.82 s and 285.33±10.50 s when the osmotic pressure of Na⁺solution was 282.36 k Pa.Which was significantly higher than those in the other groups（P<0.05）.The maximum FT and LT was 36.00±0.82 s and 130.33±10.96 s when the osmotic pressure of K⁺solution was 211.77 k Pa.Which was significantly higher than those in the other groups（P<0.05）.The maximum FT and LT was 43.67±1.70 s and 355.33±10.61 s when the osmotic pressure of glucose solution was 352.95 k Pa.Which was extremely significantly higher than those in the control group（P<0.01）.The maximum FT and LT was 45.00±1.63 s and 372.67±7.13 s when the osmotic pressure of fructose solution was 352.95 k Pa.Which was significantly higher than those in the other groups（P<0.05）.The maximum FT and LT was 40.00±2.45 s and 357.00±6.98 s when the osmotic pressure of galactose solution was 235.30 k Pa.Which was significantly higher than those in the other groups（P<0.05）.The maximum FT and LT was 30.00±2.16 s and 100.33±4.11 s when p H solution was 8.0.FT was significantly higher than those in the other groups（P<0.05）.LT had no significant difference with p H 8.5 group（P>0.05）,but was extremely significantly higher than other p H groups（P<0.01）.（2）The comprehensive regulation test results of fructose,p H and Na⁺solutions on sperm motility of the R.rutilus lacustris（Pallas）showed that:the optimal formula for comprehensive regulation of sperm motility of the R.rutilus lacustris（Pallas）was 117.65 k Pa of fructose and 188.24 k Pa of Na⁺mixed solution,which p H was 8.0,and the actual FT and LT sperm was 58.3±7.9 s and 370.0±21.9 s.The regulation intensity is fructose>Na⁺>p H.（3）The results of the individual fecundity test of the R.rutilus lacustris（Pallas）show that:The absolute fecundity of the R.rutilus lacustris（Pallas）was 1684.12～27742.82 eggs,the average was（10572.70±5793.67）eggs,the relative fecundity of body weight was 71.23～229.82 eggs/g,the average was（140.57±29.77）eggs/g,and the relative fecundity of body length was 16.19～144.03 eggs/mm,the average was（65.66±27.43）eggs/mm.The regression equation between body length and body weight was expressed as W=7E-06L^3.211（R²=0.955）.The R.rutilus lacustris（Pallas）absolute fecundity and relative fecundity of body length were the strongest correlations with gonad weight.The regression equations were F=1569.826W_G^0.834（R²=0.917,P<0.01）and F_L=15.556W_G^0.641（R²=0.894,P<0.01）respectively.The fitting effect between the relative fecundity of body weight and the coefficient of GSI was the best.The regression equation was F_W=e^{（5.382-6.637/GSI）}（R²=0.624,P<0.01）.Stepwise regression analysis results:The prediction equation of the absolute fecundity of the R.rutilus lacustris（Pallas）was:F=552.411W_G+69.610W-35.358（R²=0.933,P<0.01）.The prediction equation for the relative fecundity of the R.rutilus lacustris（Pallas）body weight was:F_W=4.078GSI+73.816（R²=0.558,P<0.01）.The prediction equation for the relative fecundity of the R.rutilus lacustris（Pallas）body length was:F_L=3.227W_G+20.723K+0.259L-45.411（R²=0.881,P<0.01）.Egg diameter distribution was inferred that R.rutilus lacustris（Pallas）spawn was once in a year.In this study,it was concluded that the sperm of the R.rutilus lacustris（Pallas）had better sperm motility in Na⁺solution with osmotic pressure of 188.24～376.48 k Pa,K⁺solution with 141.18～282.36 k Pa,and glucose,fructose and galactose solution with 235.30～352.95 k Pa.The optimum p H range for sperm is between 7.5 and 8.5.The R.rutilus lacustris（Pallas）spawn was once in a year.The absolute fecundity of the R.rutilus lacustris（Pallas）was 1684.12～27742.82 eggs,the average was（10572.70±5793.67）eggs,the relative fecundity of body weight was 71.23～229.82 eggs/g,the average was（140.57±29.77）eggs/g,and the relative fecundity of body length was 16.19～144.03 eggs/mm,the average was（65.66±27.43）eggs/mm.Thepredictionequationoftheabsolutefecunditywas:F=552.411W_G+69.610W-35.358（R²=0.933,P<0.01）.The above results and conclusions enriched the reproductive biology of the R.rutilus lacustris（Pallas）,and provided some theoretical support for the protection and proliferation of the R.rutilus lacustris（Pallas）population resources.