Lernaea cyprinaceainfection in a new hostPuntius pulchellusin intensive culture system and its control by doramectin.
The present study explored the susceptibility ofPuntius pulchellussubadults toLernaea cyprinaceainfection subsequent upon their first introduction to an intensive culture system that had a previous history ofLernaeainfection and evaluated the efficacy of doramectin against the parasite. All theP. pulchellusintroduced to the culture pond got infected demonstrating 100 % susceptibility of this species toLernaeainfection. Pathological changes caused by the parasite as evidenced by the extensive hemorrhage and tissue necrosis of the host at the point of parasite attachment was most severe inP. pulchellus. On the contrary, among the fish species already present in the pond and were previously exposed to the infection before the start of the present study, onlyLabeo fimbriatusdeveloped mild to moderate infection.Cirrhinus mrigala,Ctenopharyngodon idellaandCyprinus carpiofrom the same culture pond did not developLernaeainfection. Doramectin administration at 1 mg/kg b.wt. of fish incorporated in feed and given orally for 10 days or by a single intramuscular injection at 200 μg/kg b.wt. was found to be effective in controllingL. cyprinaceaadult parasite infection inP. pulchellus. Doramectin hastened healing of the wounds caused byL. cyprinaceaand did not cause any noticeable adverse reactions or toxicity to the fish host during the present study. In conclusion,P. pulchelluswas observed to be highly susceptible toL. cyprinaceaupon its first exposure to the infective stages of the parasite and a single intramuscular injection of doramectin at 200 μg/kg b.wt. was more effective than oral administration of the drug in controllingL. cyprinaceainfection.
Regional Research Centre, Central Institute of Freshwater Aquaculture, Hessarghatta Lake P.O., Bangalore, Karnataka 560 089 India.
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0000-0002-9555-9514
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Hemaprasanth
Regional Research Centre, Central Institute of Freshwater Aquaculture, Hessarghatta Lake P.O., Bangalore, Karnataka 560 089 India.
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Sridhar
Regional Research Centre, Central Institute of Freshwater Aquaculture, Hessarghatta Lake P.O., Bangalore, Karnataka 560 089 India.
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Raghuanth
Doramectin; Efficacy; Intensive culture; Lernaea cyprinacea; Puntius pulchellus; Susceptibility