5种药物对异育银鲫"中科3号"受精卵孵化的影响

在水温21~23℃,pH 6.2~6.5条件下,采用半静水试验法,按等对数间距设置药物质量浓度梯度,日换水50%,补充药物50%,24 h观察记录1次,比较美婷Ⅱ、霉灵、纳他霉素、杀毒矾和高锰酸钾5种药物对异育银鲫"中科3号"受精卵水霉抑制作用及孵化率的影响。试验结果显示,试验药物对受精卵水霉生长均有一定抑制作用,其抑霉率为美婷Ⅱ>霉灵>高锰酸钾、纳他霉素和杀毒矾,但杀毒矾对异育银鲫"中科3号"受精卵的毒副作用较大,显著降低了受精卵孵化率,不宜使用;美婷Ⅱ、霉灵、纳他霉素和高锰酸钾对异育银鲫"中科3号"受精卵的适宜使用质量浓度分别为4.90~6.50、1.97~3.87、1.50、2.50 mg/L,使用方法为长时间浸浴,可有效抑制受精卵孵化过程中水霉的生长,显著提高受精卵孵化率,适合在异育银鲫"中科3号"受精卵孵化过程中使用。

Effects of Five Drugs on Hatchability of Fertilized Eggs in CAS Ⅲ Strain of Allogynogenetic Silver Crucian Carp

Fertilized egg adhesion on 5 cm×10 cm mesh patch of CASⅢstrain of allogynogenetic silver crucian carp Carassius auratus gibelio were incubated in a 5 L plastic bucket and exposed to five drugs Mei tingⅡ,Mei ling,Natamycin,oxadixyl mancozeb and potassium permanganate prepared by stock of 1000 mg/L by equal interval between logarithm at water temperature 21-23℃and pH 6.2-6.5 by using a semi-static test method to explore for the inhibition of water mold Saprolegnia and hatchability in fertilized eggs by the medicines.The results showed that all of 5 medicines had some inhibitory effects on the water mold of the fertilized eggs,with larger inhibition rate in Mei tingⅡthan in Mei ling and larger inhibition rate in Mei ling than in Natamycin,oxadixyl mancozeb and potassium permanganate.The toxicity and side effects of oxadixyl mancozeb were found to be significantly decreased in hatchability,with precautions utilization,and optimal dose of 4.90-6.50 mg/L in Mei tingⅡ,1.97-3.87 mg/L in Mei ling,1.50 mg/L in Natamycin and 2.50 mg/L in potassium permanganate in immersion.These findings suggest that Mei tingⅡ,Mei ling,Natamycin and potassium permanganate be effective for controlling Saprolegnia of fertilized eggs in allogynogenetic silver crucian carp CASⅢduring incubation.