Screening of Saprolegniasis Preventive Drugs for Golden Trout (Oncorhynchus mykiss) Fertilized Eggs During Hatching

In order to screen the effective preventive drugs for saprolegniasis occurred during hatching of the fertilized eggs of golden trout, effects of two kinds of self-made Chinese herbal compounds（AB） and two kinds of chemical bactericides（peroxyacetic acid andhydrogen peroxide, CD） with three disinfection concentrations were compared in this study. The fertilized eggs of golden trout were randomly divided into 13 groups, each group with two parallels of 1 000 eggs. Drugs at high,medium and low concentration were respectively used to immerse the fertilized eggs35 min for disinfection once a day. The numbers of live and dead eggs were recorded each day before disinfection and the numbers of survival eyed eggs were counted in each experimental group after finishing the whole test. The results indicated that all of four kinds of drugs used here had a certain effect on prevention and control of saprolegniasis during hatching of fertilized eggs of golden trout, and also showed a correlation between the concentrations and effects. After the selection of several drugs, we found that group B-medium, C-medium and D-high exhibited the most remarkable effects on control of saprolegniasis. However, careful consideration should be given to chemical drugs residues and their potential hazard to the eyed eggs. Therefore, Chinese herbal compound B was suggested to be used for prevention and control of saprolegniasis to achieve the healthy aquaculture. And the concentration and operation time of Chinese herbal compound B should be strictly controlled when used in disinfection of fertilized eggs.

甘肃地区几种鲑鳟鱼肌肉营养成分比较与评价

为了解甘肃地区养殖鲑鳟鱼的营养价值与鲜美程度,采用常规营养测试方法测定虹鳟(Oncorhynchus mykiss)、金鳟(golden Oncorhynchus mykiss)、亚东鲑(Salmo trutta fario)及七彩鲑(Salvelinus fontinalis)四种商品鱼(体质量835.72~989.12 g)的肌肉营养成分。结果显示:鱼肌肉(鲜样)中水分的质量分数为70.80%~75.00%、粗蛋白18.40%~19.20%、粗脂肪4.00%~10.10%和粗灰分1.20%,除粗灰分含量外各组间差异显著,金鳟是典型高蛋白高脂肪品种。共检测出18种氨基酸,其中人体必需的8种氨基酸总量为7.69%~8.43%(干样,下同);4种鲑鳟鱼肌肉中必需氨基酸组成均与FAO/WHO要求一致,必需氨基酸指数为84.40~86.56;限制性氨基酸一致为色氨酸,4种鲜味氨基酸总质量分数为38.52%~39.25%,各组间差异显著,从各种氨基酸分析得出亚东鲑是相对组成最理想的品种。肌肉中脂肪酸含量丰富(21~23种),多不饱和脂肪酸含量达1.80%~4.83%,其中DHA+EPA含量为0.39%~0.90%,各组间差异显著,但虹鳟保健价值更有优势。9种常见的矿物元素被检测出,各组间差异显著,其中七彩鲑矿物元素相对较高,生理功效突出。研究表明4种养殖鲑鳟鱼营养价值均较高。