The aims of this study were to diagnose coenurosis by means of computerized tomography (CT) scan imaging and molecular characterization of the CO1 gene using the polymerase chain reaction (PCR). Sheep and calves were necropsied, and CT scans on the cephalic region were performed on the animals. Sections of brain tissue infected with parasites were then stained with hematoxylin and eosin for mic...

—Fry of rainbow trout Oncorhynchus mykiss held as sentinel fish became infected with Myxobolus cerebralis when held at all juvenile acclimation sites for spring Chinook salmon O. tshawytscha and steelhead O. mykiss (anadromous rainbow trout) and thus expand the known range of M. cerebralis in northeastern Oregon. In spring 2001, replicate cages of rainbow trout fry were placed at the intake sit...

A nested polymerase chain reaction (PCR) assay was used to detect early stages of Myxobolus cerebralis in caudal and adipose fin samples from rainbow trout (RT). To determine sensitivity, groups of 10 RT were exposed to 2,000 M. cerebralis triactinomyxons/fish for 1 hour at 15 degrees C and subsequently moved to clean recirculating water. Fish were held for 2 and 6 hours and 1, 2, 3, 5, 7, 10, ...

Salmonid species vary substantially with respect to both susceptibility and pathology when challenged with Myxobolus cerebralis (O’Grodnick 1979). Even within a species, strain differences in susceptibility have been demonstrated (Densmore et al. 2001). Rainbow trout are generally accepted to be one of the most susceptible species to M. cerebralis infection, yet are one of the most popular spor...

Single-round polymerase chain reaction (PCR) and pepsin-trypsin digest (PTD) methods were compared for the detection of Myxobolus cerebralis. Parallel tests were conducted on a total of 1743 free-ranging and 400 hatchery-reared salmonids. Concurrent results were found in 84.6% of the free-ranging fish samples, and 83.5% of the hatchery samples. PCR identified M. cerebralis more frequently than ...

During seasonal epizootics of neurologic disease and mass mortality in the summers of 1992, 1993 and 1994 on a sea-farm in Ireland, Atlantic salmon Salmo salar smolts suffered from encephalitis associated with infection by a neurotropic parasite. Based on ultrastructural studies, this neurotropic parasite was identified as an intercellular presporogonic multicellular developmental stage of a hi...

—Studies of the whirling disease epizootic in the upper Colorado River drainage have suggested that Windy Gap Reservoir is a source of the fish-infective actinospore of Myxobolus cerebralis. We divided the reservoir into four quadrants (12 zones) and conducted a core-sampling study to determine the spatial dynamics of actinospore production within the reservoir from late June to early November ...

The effects of ultraviolet (UV) irradiation on the viability of the waterborne triactinomyxon stages of Myxobolus cerebralis were evaluated by vital staining and the infectivity for juvenile rainbow trout Oncorhynchus mykiss. A dose of 1300 mWs cm-2 was required to inactivate 100% of the triactinomyxons held under a static collimated beam of UV as determined by vital staining. Juvenile rainbow ...

Whirling disease is a serious problem that impacts wild and hatchery salmonid stocks across the globe. Whirling disease is caused by a microscopic parasite, Myxobolus cerebralis, with a complex life history involving both salmonid and oligochaete worm hosts. In this study, we investigated the capability of wildland firefighting foams to inactivate M. cerebralis by indirect methods. Specifically...