Publications

The introduction of American shad from the Atlantic to the Pacific coast of North America in the late 1800’s and the subsequent population expansion in the 1980’s resulted in the amplification of Ichthyophonus sp., a Mesomycetozoean parasite of wild marine fishes. Sequence analysis of the ribosomal DNA gene complex (small subunit and internal transcribed spacer regions) and Ichthyophonus epidemiol

Viral hemorrhagic septicemia virus (VHSV) is a rhabdovirus found in fish from oceans of the northern hemisphere and freshwaters of Europe. It has caused extensive losses of cultured and wild fish and has become established in the North American Great Lakes. Large die-offs of wild fish in the Great Lakes due to VHSV have alarmed the public and provoked government attention on the introduction and s

There are three main genetic lineages or genogroups of Infectious hematopoietic necrosis virus (IHNV) in N. America. Strains representing the M genogroup are more virulent in rainbow trout relative to the U genogroup. In this study, we used microarray analysis to evaluate potential mechanisms responsible for host-specific virulence in rainbow trout that were given intraperitoneal injections of buf

From the mid-1980s through the early 1990s, outbreaks of bacterial kidney disease (BKD) caused by Renibacterium salmoninarum continued in Chinook salmon Oncorhynchus tshawytscha in Idaho Department of Fish and Game (IDFG) hatcheries despite the use of three control methods: (1) injection of returning adult fish with erythromycin to reduce prespawning BKD mortality and limit vertical transmission o

The rise of aquaculture has been one of the most profound changes in global food production of the past 100 years. Driven by population growth, rising demand for seafood and a levelling of production from capture fisheries, the practice of farming aquatic animals has expanded rapidly to become a major global industry. Aquaculture is now integral to the economies of many countries. It has provided

Chinook salmon Oncorhynchus tshawytscha are highly susceptible to Renibacterium salmoninarum, the causative agent of bacterial kidney disease (BKD). Previously we demonstrated that introduced Chinook salmon from Lake Michigan, Wisconsin (WI), USA, have higher survival following R. salmoninarum challenge relative to the progenitor stock from Green River, Washington, USA. In the present study, we in

Differential virulence of infectious hematopoietic necrosis virus (IHNV) isolates from the U and M phylogenetic subgroups is clearly evident in the Redfish Lake (RFL) strain of sockeye salmon Oncorhynchus nerka. In these fish, experimental immersion challenges with U isolates cause extremely high mortality and M isolates cause low or no mortality. When survivors of M virus immersion challenges wer

Rainbow trout, Oncorhynchus mykiss, were infected with Ichthyophonus sp. and held at 10°C, 15°C and 20°C for 28 days to monitor mortality and disease progression. Infected fish demonstrated more rapid onset of disease, higher parasite load, more severe host tissue reaction and reduced mean‐day‐to‐death at higher temperature. In a second experiment, Ichthyophonus‐infected fish were reared at 15°C f

Characterization of infectious haematopoietic necrosis virus (IHNV) field isolates from North America has established three main genogroups (U, M and L) that differ in host-specific virulence. In sockeye salmon, Oncorhynchus nerka, the U genogroup is highly virulent, whereas the M genogroup is nearly non-pathogenic. In this study, we sought to characterize the virus-host dynamics that contribute t

The efficacy of a novel vaccine composed of three short recombinant subunit Pasteurella multocida toxin (PMT) proteins in combination with a bi-valent P. multocida whole-cell bacterin (rsPMT–PM) was evaluated in field studies for prevention and control of progressive atrophic rhinitis (PAR) of swine at 15 conventional farrow-to-finish farms. Experimental piglets that were immunized twice with the

Parvicapsula minibicornis is a myxosporean parasite that is associated with disease in Pacific salmon during their freshwater life history phase. This study reports the development of a quantitative (real-time) polymerase chain reaction (QPCR) to detect P. minibicornis DNA. The QPCR assay targets the 18S ribosomal subunit gene. A plasmid DNA control was developed to calibrate cycle threshold (CT)

No abstract available.