拉萨裂腹鱼鱼卵振动敏感性及其适宜孵化模式

Vibration Sensitivity and Suitable Hatching Mode of Schizothorax waltoni Eggs

将同一批繁殖的3尾拉萨裂腹鱼受精卵平分为3份,分别在流水的平列槽、立式孵化器和圆柱形孵化器中孵化,比较不同孵化容器的孵化效果。另一尾鱼的受精卵于平列槽中孵化,用水浴恒温振荡器振荡5min,频率分别为0、50、100、150、200、250r/min(换算为水流速率分别为0、0.157、0.314、0.471、0.628、0.785m/s),统计死卵数,探索拉萨裂腹鱼胚胎对振动的敏感性。试验结果表明,平列槽孵化率最高,受精率为91.23%、64.26%、45.66%的受精卵孵化率分别为81.74%、40.30%、6.08%;其次为立式孵化器,3种受精率的受精卵孵化率分别为32.77%、2.59%、0;圆柱形孵化器孵化率最低,3种受精率的受精卵孵化率分别为5.42%、0、0。流速为0时,受精卵死亡率最低为(0.22±0.15)%,与流速为0.157~0.471m/s组差异不显著。流速为0.157~0.628m/s组受精卵死亡率组间差异不显著;流速0.785m/s组死亡率最高,显著高于其他试验组。0~0.471m/s条件下,原肠晚期死亡率最高[(10.00±5.61)%],其次为多细胞期[(5.83±2.85)%]。0.157~0.628 m/s条件下64细胞期死亡率最高[(26.67±23.45)%],与原肠晚期、多细胞期差异不显著。0.785m/s条件下心脏原基及心脏搏动期死亡率最低(0),其余各发育时期均较高。拉萨裂腹鱼不同发育时期受精卵对水流速率有不同程度的敏感性,建议采用流速较小的平列槽对其受精卵进行孵化。

The fertilized eggs(with fertility of 91.23%,64.26%and 45.65%)of Schizothorax waltoni derived from the same batch of eggs were randomly divided into three parts and incubated in three types of incubators to compare three incubation patterns of S.waltoni eggs and the embryos of different developmental stages were oscillated at frequency of 0,50 r/min(0.157 m/s),100 r/min(0.314 m/s),150 r/min(0.471 m/s),200 r/min(0.628 m/s)and 250 r/min(0.785 m/s)for 5 minutes to explore the sensitivity of the embryos to shock.The results showed that the descending order of hatching rate was expressed as horizontal incubator(fertilization rate of 91.23%,64.26%,and 45.65%;hatching rate of 81.74%,40.30%,and 6.08%)>vertical incubator(91.23%,64.26%,and 45.65%;32.77%,2.59%,and 0)>cylindrical incubator(91.23%,64.26%,and 45.65%;5.42%,0,and 0).The minimal mortality[(0.22±0.15)%]was found in the embryos exposed to flowing rate of 0,without significantly different from that in the embryos exposed to flowing rate of 0.157—0.471 m/s,There was no significant difference in themortality of fertilized eggs between groups with flowing rates of 0.157—0.628 m/s.The maximal mortality was found in the 0.785 m/s group,which was significantly higher than that in the other groups.Under the condition of 0—0.471 m/s,the maximal mortality[(10.00±5.61)%]was found in the late gastrula stage,followed by the multicellular stage[(5.83±2.85)%].Under the condition of 0.157—0.628 m/s,the maximal mortality[(26.67±23.45)%]was found in the 64-celled stage,which was not significantly different from that in the late gastrula stage and multicellular stage.The minimal mortality(0)was found in the rudimental heart and heart beating stages in 0.785 m/s group,which was lower than that in the other developmental stages.S.waltoni embryos was sensitive to flowing rate at different developmental stages.It is suggested to hatch the fertilized eggs in a horizontal incubator with a low flowing rate.