庆丰霉素防治草、青鱼粘细菌烂鳃病的试验

本文介绍了用庆丰霉素防治草、青鱼粘细菌烂鳃病的试验结果。试验表明，防治草、青鱼烂鳃病，以采用投喂口服为宜。治疗药量为每100斤成鱼每天投喂庆丰霉素(固体)半斤(含250万单位)，连投三天，有效率达96％；每100斤夏花鱼种，每天投喂1斤(含500万单位)，连投4天，有效率为72．7％。预防的投药方式和治疗剂量相同，唯应在该病流行季节之前投喂，夏花鱼种以连投7天为宜。试验表明，成鱼投药组死亡率为1．7％，对照组死亡率达27％；夏花鱼种投药组死亡率为15．7％，对照组死亡率为40．3％。

APPLICATION OF QINGFENGMYCIN AS A PROPHYLACTIC AND THERAPEUTICAL AGENT FOR GILL-ROT DISEASE INCITED BY PATHOGENIC MYXOBACTERIA

Qingfengmycin is an antibiotic produced by Streptomyces qingfengmyceticus.The antibiotic can inhibit the growth of Myxobacteria and thus it can be used as a fineprophylactic and therapcutical agent for gill-rot fish disease infected by pathogenicMyxobacteria on black carp (Mylopharyngodon piceus) and grass carp (Ctenopharyn-godon idellus). The better way of treatment is to feed the sick fishes with theantibiotic mixed with food. The therapeutical dosage of qingfnegmycin for adult fish was 2.5 million unitsper 50 kilogram body weight daily. The recovery rate was 95% when the drug wasapplied succesively for three days. For young fish a dosage of 5 million units per 50kilogram body weight was applied and the recovery rate was 72.7%. If both adult andyoung fish were given a prophylactic treatment with the antibiotic before the epidemicseason it was found that the mortality of the treated adult fish was 1% while 27% inthe control. The mortality of the treated young fish wag 15.7% while 40.3% in thecontrol. Qingfengmycin can be produced by conventional solid fermentation method.Morever, the material which used as culture medium for the Streptomyces can also beused as additional fish food. The antibiotic is non-toxic and inexpensive.