VHSv - Visual Identification

Topics concerning muskellunge and fisheries research, diseases, stocking and management.
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Will Schultz
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Joined: Wed Apr 06, 2005 11:06 pm
Location: GR, MI

VHSv - Visual Identification

Post by Will Schultz » Fri Jun 01, 2007 9:34 am

Piscirickettsia
Skin lesions (open sores) are not something common with VHSv. Those are common with Piscirickettsia (muskie pox) and look somewhat like a lamprey scar. Here is an example of Piscirickettsia:
Image


VHSv
Again, open lesions are NOT common with VHSv. Here is a photo of what VHSv hemorrhaging looks like on a shad. This is what the bleeding also looks like under the skin of muskellunge. Since muskellunge fins are usually red identifying these streaks in the fins of muskellunge will be difficult.

Image


Clinical/Visual signs of VHSv
VHSv may cause tissue hemorrhaging(see photo above), bulging eyes and bloating. Unfortunately, it isn't possible to diagnose VHSv by looking at a fish because there are other diseases and causes for the visual signs noted above. The only way to confirm VHSv is to test the fish. It is important to note that not all fish infected show signs of VHSv and may become carriers of the disease. The only way to confirm VHS is to test the fish in a lab.


Michigan DNR asks that you report fish that appear to be infected:
Citizens are encouraged to report sick fish or fish kills to their local DNR office or use the DNR Web site at www.michigan.gov/dnr. Anglers should contact the DNR if they observe fish that exhibit any of the following signs: hemorrhaging in the skin, including large red patches particularly on the sides and anterior portion of the head; multiple hemorrhages on the liver, spleen, or intestines; or hemorrhages on the swim bladder that give the otherwise transparent organ a mottled appearance. This information will help DNR fisheries staff to track VHS and take appropriate management actions to help slow the spread of this virus.
Self interest is for the past, common interest is for the future.

Hamilton Reef
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Joined: Thu Apr 28, 2005 9:43 am
Location: Montague, MI on White River

Post by Hamilton Reef » Mon Jul 02, 2007 8:24 pm

DNR doesn't want individual VHS-suspect fish
But fish kills can be reported

http://www.ludingtondailynews.com/news. ... y_id=36708

BRIAN MULHERIN - DAILY NEWS STAFF WRITER
bmulherin@ludingtondailynews.com 843-1122, ext. 348

Got a single fish that you think has viral hemorrhagic septicemia?
The Department of Natural Resources probably doesn’t want it.

After two anglers from Lake Michigan reported salmon that looked diseased, the DNR was asked what anglers should do when they get a fish they think might have VHS.

Fisheries Biologist Todd Grischke said, in short, they should do nothing.

The DNR is conducting its own sampling this summer and is also working with commercial fishers to get fish. Creel census clerks will also pick up samples from recreational anglers who believe they have infected fish.

There is no hotline to report a fish suspected of having VHS. Fish have so many diseases it can be hard for an angler to tell one disease from another. A fish with excessive bodily fluid may have bacterial kidney disease, which is known to surface in fish populations from time to time. A fish with bloody streaks in the meat might have VHS or it might have some other disease.

Grischke said DNR biologists are overwhelmed with testing the samples they already have.

There is, however, an e-mail address where large fish kills can be reported, DNR-FISH-Report-Fish-Kills@michigan.gov.

Grischke said anglers who have a fish they believe is suffering from a disease can dispose of it in the same way they would other fish and remains. He said there is no concern over spreading VHS by grinders at fish-cleaning stations as long as the wastewater plant where the discarded fish end up drains into the same body of water where the fish was caught.

In other words, Lake Michigan salmon can be ground up and discharged into Lake Michigan, but Lake Huron salmon should be cleaned at a Lake Huron cleaning station.

Although there were widespread reports that VHS-positive fish were found in Wisconsin waters of Lake Michigan, the lake remains classified as “under surveillance” for VHS and not infected.

Grischke added that information will be made available as soon as possible if VHS is confirmed anywhere in the state.

“As we find VHS in areas, we’ll report it immediately when it’s confirmed,” he said.

Hamilton Reef
Posts: 1156
Joined: Thu Apr 28, 2005 9:43 am
Location: Montague, MI on White River

Post by Hamilton Reef » Wed Aug 22, 2007 12:19 am

Getting to know your new neighbor: VHS

Recently Gary Whelan, Fish Production manager for the Michigan Department of Natural Resources, gave an overview of VHS —Viral Hemorrhagic Septicemia.

http://www.thealpenanews.com/stories/ar ... cleID=5238

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