Michael  Kent
Michael Kent

Fish Diseases

OSU Campus
Fisheries and Wildlife
Nash Hall
Room 532 Oregon State University
Corvallis, OR 97331
United States
(541) 737-8652


Presently the Kent lab is focusing on two major research areas; diseases of zebrafish in research facilities and impacts of pathogens on wild salmonid fishes. In both areas, we are focusing on the study of chronic infectious diseases. In the past decade there has been a dramatic increase in the use of zebrafish as a model in biomedical research. Underlying chronic diseases are of concern as they relate to non-protocol induced variation in laboratory fish, as they would with any laboratory animal. Microsporidosis (caused by Pseudoloma neurophilia) and mycobacteriosis (caused by various species of Mycobacterium) are the diseases under investigation at this time. This work is supported by NIH NCRR.  Dr. Kent is also a co-PI at the Zebrafish International Resource Center, where he assists with health studies and their diagnostic service. We also have an on-line manual on zebrafish diseases.

We recently established the SPF (Specific Pathogen Free) zebrafish research colony here at OSU at the Sinnhuber Aquatic Resource Center in collaboration with Dr. Robert Tanguay. This was supported by the NIEHS Environmental Health Sciences Center and NIH NCRR. Relating to our zebrafish studies, Drs. Kent and Tanguay oversee a T-32 training grant from NIH NCRR to provide research training to veterinarians with aquatic models.

Regarding salmonid fishes, we recently completed a multi-year study on the impacts of parasites on overwinter survival in coho salmon from the West Fork Smith River in Oregon. These fish are Endangered Species Act (ESA) listed as “threaten”. Work was supported by the Oregon Department of Fish and Wildlife. We are now investigating the role of multiple pathogen infections with prespawning Chinook salmon from the Willamette River in collaboration with Dr. Carl Schreck, OSU and Dr. Chris Claudill, University of Idaho, and through support of the U.S. Army Corps of Engineers.

Dr. Kent also investigates other parasites, including those infecting terrestrial animals. Recently we described spirurid nematodes in cougars in Oregon and modified a new diagnostic test for Haemonchus contortus, an important trichostongyle nematode of sheep, goats and camilds (See publications below).  We also showed that  what were thought to be gonadal tumors in arrow gobies are actually lesions caused by a new species of Ichthyosporidium (Microsporidia).


MB 480 General Parasitology
VMB 760 Veterinary Parasitology


Sanders, J., Myers, M.S., Tomanek, L., Cali, A M., Takvorian, P,M.  Kent, M.L. 2012.  Ichthyosporidium weissii n. sp. (Microsporidia) infecting the arrow goby (Clevelandia ios).  J. Eurk. Microbiol. (in press)

Ferguson, J.A., Koketsu, W.,  Ninomiya, I.,  Rossignol,  P.A.,  Jacobson, K.C., Kent, M.L. 2011.  Mortality of coho salmon (Oncorhynchus kisutch) associated with burdens of multiple parasite species.  Intl. J. Parasitol. 41: 1197-11205.

Sanders JL, Kent ML 2011. Development of a sensitive assay for the detection of Pseudoloma neurophilia in laboratory ­populations of the zebrafish Danio rerio. Dis Aquat Org. 96:145-156

Ferguson, J.A., Romer, J., Sifneos, J., Madsen, L, Glynn, M., Schreck, C.B., Kent, M.L.  2012. Impacts of multispecies parasitism on juvenile Oregon Coho Salmon (Oncorhynchus kisutch).  Aquaculture  (in press, available online).

Ferguson, J. A., St-Hilaire, S., Peterson, T.S., Rodnick, K., Kent, M.L. 2011. Survey of  parasites in threatened stocks of coho salmon (Oncorhynchus kisutch) in Oregon by   examination of wet tissues and histology.  J. Parasitol.  97: 1085-1098.                                                                      

Kent, M.L., Harper, C., Wolf, J.C.  2011. Research impacts of subclinical  diseases in zebrafish. ILAR J.  (in press).

Peterson, T.S., Spitsbergen, J.M., Feist, S.W., Kent, M.L. 2011. The Luna stain, an improved selective stain for detection of microsporidian spores in histologic sections. Dis. Aquat. Org.  95: 175–180.

Kent, M.L., Buchner, C., Watral, V.G., Sanders, J.L. LaDu, J., Peterson, T.S., Tanguay, R.L. 2011. Development and maintenance of a specific pathogen free (SPF) zebrafish research facility for Pseudoloma neurophilia.  Dis. Aquat. Org. 95: 73–79.

Ferguson, J.A., Woodberry, K., Gillin, C.M., Jackson, D.H., Sanders, J., Madigan, W., J. Bildfell, R.J., Kent, M.L. 2011. Cylicospirura species (Nematoda: Spirocercidae) and stomach nodules in cougars (Puma concolor) and bobcats (Lynx rufus) in OregonJ. Wildl. Dis. 47:140-153.

Brown, A. M. V., Kent, M.L., Adamson, M.L. 2010. Description of five new Loma (Microsporidia) species in Pacific Fishes with redesignation of the type species Loma morhua Morrison & Sprague, 1981, based on morphological and molecular species-boundaries tests. J. Eurk. Microbiol. 57: 529-553.

Jurasek, M.E. Bishop-Stewart, J.K., Storey, B.E., Kaplan, R.M., Kent, M.L.  2010. Modification and further evaluation of a fluorescein-labeled peanut agglutinin test for identification of Haemonchus contortus eggs. Vet. Parasitol.  69:209-213.

Sanders, J.L., Lawrence, C., Nichols, D.K., Bru  , J.F., Peterson, T.S., Murray, K.N., Kent, M.L. 2010. Pleistophora hyphessobryconis (Microsporidia) infecting  zebrafish 9911:47-56 (2010)

Brown, A.M.V., Kent, M.L., Adamson, M.L. 2010.  Low genetic variation in the salmon and trout parasite Loma salmonae (Microsporidia) supports marine transmission and clarifies species boundaries. Dis. Aquat. Org. 91:35-46.

Mansfield, K.G., Riley, L., Kent, M.L.  2010. Workshop summary: detection, impact, and control of specific pathogens in animal resource facilities. ILAR. 51:171-179.

Whipps, C.M., Boorom, K., Bermudez, L.E., Kent, M.L. 2010. Molecular characterization  of Blastocystis species in Oregon identifies multiple subtypes. Parasitol. Res. 106: 827-832.

Landers, D.H. , Simmonich, S.M., Jaffe, D., Geiser, L., Campbell, D.H., Schwindt, A.,  Schreck, C.B., Kent, M.L., Hafner, W., Kimberly, H., Usenko, S., Ackerman, L., Schrlau,     J., Rose, N., Blett, T.,  Erway, M. M. 2010. The Western Airborne Contaminant Assessment Project (WACAP): An Interdisciplinary Evaluation of the Impacts of Airborne Contaminants in Western U. S. National Parks. Environ. Sci. Tech. Environ.44: 855–859.

Ramsay, J.M., Watral, V., Schreck, C.B., Kent, M.L. 2009. Husbandry stress exacerbates mycobacterial infections in adult  zebrafish, Danio  rerio (Hamilton). J. Fish Dis. 32: 931-941.

Schwindt, A.R., Kent, M.L., Ackerman, L.K., Simonich, S.L., Landers, D.H., Blett, Schreck, C.B. 2009. Reproductive abnormalities in fish from western U.S. National Parks. Trans. Am. Fish Soc. 138: 522-531.

Jacobs, J.M., Stine, C.S., Baya, A.M., Kent, M.L. 2009. A review of mycobacteriosis  in marine fishes. J. Fish Dis. 32: 119-130.