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实验研究了离体条件下温度对坏鳃指环虫(Dactylogyrus vastator)产卵和孵化的影响,以及在20℃、在体条件下坏鳃指环虫的产卵和发育过程。在离体条件下,坏鳃指环虫的平均产卵量随着温度的升高而增加,在4、10、20、30和35℃时,其平均产卵量分别为0.25、5.9、9.1、9.2和13.4枚/虫;除4℃外,绝大多数虫卵是在离体后的前5h内产出;然而,在体条件下虫体的产卵是连续且稳定的,在20℃条件下平均产卵量为6.5枚/(虫·d)。虫卵的孵化时间和孵化持续的时间随着温度的升高而减少,在10、20、30和35℃条件下,孵化时间和孵化持续时间分别为19d、3d、2d、36h和24d、5d、5d、3d,而最高的孵化率(65.5%)却出现在30℃。在20℃条件下,纤毛幼虫在感染7d后90%的虫体都已成熟,因此,在此温度条件下坏鳃指环虫由虫卵发育到成虫大约需要8—10d。为了有效控制指环虫病的暴发,在第一次用药1周后要进行第二次用药。
The effect of temperature on spawning and hatching of Dactylogyrus vastator was studied experimentally and the oviposition and development of D. gill under body condition at 20 ℃. Under exogenous conditions, the average fecundity of D. gills increased with increasing temperature, and the average fecundity at 4, 10, 20, 30 and 35 ℃ were 0.25, 5.9, 9.1, 9.2 and 13.4 eggs per worm. Except for 4 ℃, most of the eggs produced in the first 5 hours after ex-vivo. However, laying eggs in the body were continuous and stable under the condition of 20 ℃ The average number of eggs laid was 6.5 / (worm · d). The hatching time and hatching duration of the eggs decreased with the increase of temperature. The hatching time and hatching duration were 19d, 3d, 2d, 36h and 24d respectively at 10, 20, 30 and 35 ℃, respectively , 5d, 3d, while the highest hatching rate (65.5%) appeared at 30 ℃. At 20 ℃, 90% of ciliates larvae mature after 7 days of infection. Therefore, it takes about 8-10 days for the larvae to grow from eggs to adults at this temperature. In order to effectively control the ring worm disease outbreak, a week after the first medication for a second medication.