Publications
Below is a list of available MMFS peer reviewed and published science.
Filter Total Items: 88
Viral replication in excised fin tissues (VREFT) corresponds with prior exposure of Pacific herring, Clupea pallasii (Valenciennes), to viral haemorrhagic septicaemia virus (VHSV)
Procedures for a viral replication in excised fin tissue (VREFT) assay were adapted to Pacific herring, Clupea pallasii, and optimized both to reduce processing time and to provide the greatest resolution between na??ve herring and those previously exposed to viral haemorrhagic septicaemia virus (VHSV), Genogroup IVa. The optimized procedures included removal of the left pectoral fin from a euthan
Authors
C.A. Grady, J.L. Gregg, R.M. Wade, J. R. Winton, P.K. Hershberger
Susceptibility of three stocks of pacific herring to viral hemorrhagic septicemia
Laboratory challenges using specific-pathogen-free Pacific herring Clupea pallasii from three distinct populations indicated that stock origin had no effect on susceptibility to viral hemorrhagic septicemia (VHS). All of the populations were highly susceptible to the disease upon initial exposure, with significantly greater cumulative mortalities occurring in the exposed treatment groups (56.3-64.
Authors
P.K. Hershberger, J.L. Gregg, C.A. Grady, R.M. Collins
Sequence analysis of the internal transcribed spacer (ITS) region reveals a novel clade of Ichthyophonus sp. from rainbow trout
The mesomycetozoean parasite Ichthyophonus hoferi is most commonly associated with marine fish hosts but also occurs in some components of the freshwater rainbow trout Oncorhynchus mykiss aquaculture industry in Idaho, USA. It is not certain how the parasite was introduced into rainbow trout culture, but it might have been associated with the historical practice of feeding raw, ground common carp
Authors
C. Rasmussen, M. K. Purcell, J.L. Gregg, S. E. LaPatra, J. R. Winton, P.K. Hershberger
Feasibility of Surgically Implanting Acoustic Tags into Pacific Herring
Internally implanted acoustic tags represent a potentially valuable approach to assessing the seasonal migration and distribution patterns of Pacific herring Clupea palasii. We examined the feasibility of implanting two sizes of dummy acoustic tags (9 mm in diameter × 21 mm long, 1.6 g; and 7 mm in diameter × 18 mm long, 0.7 g) in Pacific herring that had been held in captivity for nearly a year a
Authors
Paul K. Hershberger, Jacob L. Gregg, A.C. Seitz, Brenda L. Norcross, J.C. Payne, A.N. Kagley, B Meloy
Release of infectious cells from epidermal ulcers in Ichthyophonus sp.–infected Pacific Herring (Clupea pallasii): Evidence for multiple mechanisms of transmission
A common clinical sign of ichthyophoniasis in herring and trout is “sandpaper” skin, a roughening of the epidermis characterized by the appearance of small papules, followed by ulceration and sloughing of the epithelium; early investigators hypothesized that these ulcers might be a means of transmitting the parasite, Ichthyophonus sp., without the necessity of ingesting an infected host. We examin
Authors
Paul K. Hershberger, Jacob L. Gregg, R. M. Kocan
Chronic and persistent viral hemorrhagic septicemia virus infections in Pacific herring
Chronic viral hemorrhagic septicemia virus (VHSV) infections were established in a laboratory stock of Pacific herring Clupea pallasii held in a large-volume tank supplied with pathogen-free seawater at temperatures ranging from 6.8 to 11.6°C. The infections were characterized by viral persistence for extended periods and near-background levels of host mortality. Infectious virus was recovered fro
Authors
Paul K. Hershberger, Jacob L. Gregg, James R. Winton, Cortney A. Grady, L. Taylor
Kinetics of viral shedding provide insights into the epidemiology of viral hemorrhagic septicemia in Pacific herring
Losses from infectious diseases are an important component of natural mortality among marine fish species, but factors controlling the ecology of these diseases and their potential responses to anthropogenic changes are poorly understood. We used viral hemorrhagic septicemia virus (VHSV) and a laboratory stock of Pacific herring Clupea pallasii to investigate the kinetics of viral shedding and its
Authors
Paul K. Hershberger, Jacob L. Gregg, James R. Winton, Courtney Grady, Rachael Collins
Amplification and transport of an endemic fish disease by an introduced species
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
Authors
Paul Hershberger, Bjorn Leeuw, Gregg Jacob, Courtney Grady, Kenneth Lujan, Susan Gutenberger, Maureen K. Purcell, James Woodson, James Winton, Michael Parsley
Prevalence of viral erythrocytic necrosis in Pacific herring and epizootics in Skagit Bay, Puget Sound, Washington.
Epizootics of viral erythrocytic necrosis (VEN) occurred among juvenile Pacific herring Clupea pallasii in Skagit Bay, Puget Sound, Washington, during 2005-2007 and were characterized by high prevalences and intensities of cytoplasmic inclusion bodies within circulating erythrocytes. The prevalence of VEN peaked at 67% during the first epizootic in October 2005 and waned to 0% by August 2006. A se
Authors
P.K. Hershberger, N.E. Elder, C.A. Grady, J.L. Gregg, C.A. Pacheco, C. Greene, C. Rice, T.R. Meyers
Differential survival of Ichthyophonus isolates indicates parasite adaptation to its host environment
In vitro viability of Ichthyophonus spp. spores in seawater and freshwater corresponded with the water type of the host from which the spores were isolated. Among Ichthyophonus spp. spores from both marine and freshwater fish hosts (Pacific herring, Clupea pallasii, and rainbow trout, Oncorhynchus mykiss, respectively), viability was significantly greater (P < 0.05) after incubation in seawater th
Authors
P.K. Hershberger, C.A. Pacheco, J.L. Gregg, M. K. Purcell, S. E. LaPatra
Inactivation of Ichthyophonus spores using sodium hypochlorite and polyvinyl pyrrolidone iodine
Chlorine and iodine solutions were effective at inactivating Ichthyophonus spores in vitro. Inactivation in sea water increased directly with halogen concentration and exposure duration, with significant differences (P < 0.05) from controls occurring at all chlorine concentrations and exposure durations tested (1.5-13.3 ppm for 1-60 min) and at most iodine concentrations and exposure durations tes
Authors
P.K. Hershberger, C.A. Pacheco, J.L. Gregg
Potential for cross-contamination of in vitro explant cultures initiated from Ichthyophonus-infected rainbow trout, Oncorhynchus mykiss (Walbaum)
[No abstract available]
Authors
S. LaPatra, R. Kocan, P. Hershberger