Thompson J.B.,Washington Animal Disease Diagnostic Laboratory |
Snekvik K.R.,Washington Animal Disease Diagnostic Laboratory |
Snekvik K.R.,Washington State University |
Vincent E.R.,Montana Fish
Journal of Aquatic Animal Health | Year: 2010
Whirling disease has been implicated in salmonid population declines in several western states. To determine the risk of a species or strain of salmonid to whirling disease it is critical to establish its relative susceptibility to Myxobolus cerebralis infection. Gila trout Oncorhynchus gilae and Apache trout Oncorhynchus gilae apache were exposed to various doses of M. cerebralis triactinomyxons (TAMs) in laboratory experiments. In trials conducted in consecutive years, fish were exposed to TAMs in doses ranging from 25 to 2,000/fish at ages ranging from 66 to 201 d posthatch (dph). All fish were held for 900 degreedays, and then the infection intensity of each fish was determined by histological examination. In 2002, 98% of the Gila trout died during exposure or within 48 h postexposure. Seventy-four percent of the Apache trout died before the end of the 90-d study period. Those that survived the entire study period had an average histological score of more than 4.0. In subsequent trials, the TAM dosage was decreased to 25-1,000/fish. Also, the age of the fish was increased from 66-72 dph to 89-201 dph. The survival rate increased from 16.0% to 49.1%. Average histological grades ranged from 1.6 to 4.8. Based on this data, it can be concluded that both Apache and Gila trout are highly susceptible to M. cerebralis in laboratory trials. © Copyright by the American Fisheries Society 2010.
U.S. Response to a Report of Infectious Salmon Anemia Virus in Western North America [Respuesta de los Estados Unidos de Norteamérica a un reporte de virus de anemia infecciosa en salmones en el oeste de Norteamérica]
Amos K.H.,National Oceanic and Atmospheric Administration |
Gustafson L.,U.S. Department of Agriculture |
Warg J.,U.S. Department of Agriculture |
Whaley J.,U.S. Department of Agriculture |
And 9 more authors.
Fisheries | Year: 2014
ABSTRACT: Federal, state, and tribal fishery managers, as well as the general public and their elected representatives in the United States, were concerned when infectious salmon anemia virus (ISAV) was suspected for the first time in free-ranging Pacific Salmon collected from the coastal areas of British Columbia, Canada. This article documents how national and regional fishery managers and fish health specialists of the U.S. worked together and planned and implemented actions in response to the reported finding of ISAV in British Columbia. To date, the reports by Simon Fraser University remain unconfirmed and preliminary results from collaborative U.S. surveillance indicate that there is no evidence of ISAV in U.S. populations of free-ranging or marine-farmed salmonids on the west coast of North America. © 2014, American Fisheries Society.
Besser T.E.,Washington State University |
Besser T.E.,Washington Animal Disease Diagnostic Laboratory |
Highland M.A.,Washington State University |
Highland M.A.,U.S. Department of Agriculture |
And 6 more authors.
Emerging Infectious Diseases | Year: 2012
Epizootic pneumonia of bighorn sheep is a devastating disease of uncertain etiology. To help clarify the etiology, we used culture and culture-independent methods to compare the prevalence of the bacterial respiratory pathogens Mannheimia haemolytica, Bibersteinia trehalosi, Pasteurella multocida, and Mycoplasma ovipneumoniae in lung tissue from 44 bighorn sheep from herds affected by 8 outbreaks in the western United States. M. ovipneumoniae, the only agent detected at significantly higher prevalence in animals from outbreaks (95%) than in animals from unaffected healthy populations (0%), was the most consistently detected agent and the only agent that exhibited single strain types within each outbreak. The other respiratory pathogens were frequently but inconsistently detected, as were several obligate anaerobic bacterial species, all of which might represent secondary or opportunistic infections that could contribute to disease severity. These data provide evidence that M. ovipneumoniae plays a primary role in the etiology of epizootic pneumonia of bighorn sheep.
Stidworthy M.F.,International Zoo Veterinary Group |
Garner M.M.,Northwest ZooPath |
Bradway D.S.,Washington Animal Disease Diagnostic Laboratory |
Westfall B.D.,Sea For Life |
And 5 more authors.
Veterinary Pathology | Year: 2014
Scuticociliatosis is an economically important, frequently fatal disease of marine fish in aquaculture, caused by histophagous ciliated protozoa in the subclass Scuticociliatida of the phylum Ciliophora. A rapidly lethal systemic scuticociliate infection is described that affected aquarium-captive zebra sharks (Stegostoma fasciatum), Port Jackson sharks (Heterodontus portusjacksoni), and a Japanese horn shark (Heterodontus japonicus). Animals died unexpectedly or after a brief period of lethargy or behavioral abnormality. Gross findings included necrohemorrhagic hepatitis and increased volumes of celomic fluid. Histologically, 1 or more of a triad of necrotizing hepatitis, necrotizing meningoencephalitis, and thrombosing branchitis were seen in all cases, with necrotizing vasculitis or intravascular fibrinocellular thrombi. Lesions contained variably abundant invading ciliated protozoa. Molecular identification by polymerase chain reaction from formalin-fixed tissues identified these as the scuticociliate Philasterides dicentrarchi (syn. Miamiensis avidus), a novel and potentially emergent pathogen in sharks. © The Author(s) 2013.
Lloyd S.J.,Washington State University |
Lloyd S.J.,University of Texas Medical Branch |
LaPatra S.E.,Washington State University |
LaPatra S.E.,Clear Springs Foods Inc. |
And 4 more authors.
Journal of Fish Diseases | Year: 2011
Strawberry disease (SD) is an inflammatory skin disorder in rainbow trout, Oncorhynchus mykiss (Walbaum). The aetiology of SD is unknown although the 16S rDNA sequence of a Rickettsia-like organism (RLO) has been associated with SD lesions using a nested PCR assay. In this study, we developed a Taqman quantitative PCR assay (qPCR) that targeted the RLO 16S rDNA sequence to examine the distribution of RLO relative to lesion status. We compared 18 lesion samples from 13 fish representing high or low lesion severity as judged by gross examination. QPCR results showed that there was a higher number of RLO sequences in high severity lesions (mean of 12068 copies) compared with fewer copies of RLO sequence in low severity lesions (mean of 3287 copies, P=0.012). Grossly normal skin samples (n=13) from SD-affected fish were all negative by qPCR except two samples (121 and 139 copies). The qPCR assay described herein is a useful tool to investigate the role of RLO in SD in the absence of a culture system for RLO. Our results demonstrate a positive correlation between copy number and lesion severity consistent with the hypothesis that the RLO is the aetiologic agent of SD. © 2011 Blackwell Publishing Ltd.
Churgin S.M.,455 North Galvkin Parkway |
Churgin S.M.,University of Wisconsin - Madison |
Garner M.M.,Northwest ZooPath |
Swenson J.,455 North Galvkin Parkway |
And 4 more authors.
Journal of Zoo and Wildlife Medicine | Year: 2013
An adult female, wild-caught red coachwhip snake (Masticophis flagellum piceus) was euthanized at the Phoenix Zoo due to severe neurologic signs. Necropsy and histopathology revealed an invasive liposarcoma of the vertebral column, which likely caused the neurologic signs. Histology of the small intestine revealed a granuloma with intralesional yeasts morphologically compatible with the genus Coccidioides. The diagnosis of coccidioidomycosis was confirmed with immunohistochemistry staining. Coccidioides posadasii is endemic to Arizona and is an important cause of disseminated fungal infections in mammals in this region. This is the first known report of intestinal coccidioidomycosis in a veterinary species and the second report of coccidioidomycosis in a reptile. Copyright 2013 by American Association of Zoo Veterinarians.