Physical and chemical effects on viability of the Myxobolus cerebralis triactinomyxon

Diseases of Aquatic Organisms

Mark Smith¹  Donald W. Roberts¹  Ronney Arndt¹  Eric J. Wagner¹ 

关键词: Myxobolus;    Whirling disease;    Disinfection;    Chlorine;    Ultrasound;   

DOI  :  10.3354/dao053133

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Various chemical and physical methods for destroying the triactinomyxon (TAM) stage of the myxozoan parasite Myxobolus cerebralis were tested. The fluorescent stains propidium iodide and fluorescein diacetate were used asindicators of viability. Physical variables tested included freezing, drying, high temperature, sonication, and pressure of 6.2 × 10⁷ Pa (9000 psi). Chemicals evaluated included chlorine bleach, povidone-iodine, andhydrogen peroxide. Freezing or drying for 1!qh was effective in killing TAMs, but pressure was not. Temperatures above 75°C for at least 5 min were also effective. Sonication with a laboratory instrument cleaner for 10 to 13 min killed and ruptured TAMs,resulting in <1.9% recovery. However, among the surviving TAMs, 39 to 58% were still viable. Chlorine concentrations of 130 ppm for 10 min were also effective at temperatures ranging from ice-water to room temperature and total hardness ranging from10 to 500 mg l^-1. Lethal concentrations of hydrogen peroxide and povidone-iodine (10% solution) were quite high: 10% for 10 min, and 50% (5000 ppm active iodine) for 60 min, respectively. The stain results indicating TAM death were verified in2 tests in which rainbow trout Oncorhynchus mykiss were exposed to TAMs that had been either frozen for 1!qh or treated with 66 ppm chlorine as sodium hypochlorite for 1 min. None of the fish exposed to the treated TAMs became infected. Theseresults should provide disinfection guidelines to prevent transfer of M. cerebralis TAMs to uninfected areas and provide information on the risks of parasite transfer under various treatment scenarios.

【 授权许可】

Unknown