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LMBV spread in livewells?

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On the thread about netting, or the lack thereof, were a couple of comments about Largemouth Bass Virus. In a recent issue of InFisherman, the study on this was reviewed. I wish I had it in front of me so I could quote some numbers.

The gist of this study was that LMBV spreads almost instantly from infected to non-infected fish in captivity. There difference was dramatic. Part of the study was to see if any handling practices associated with tournament fishing could be responsible for the spread of this disease. A group of fish was captured and held in tanks as a control group. The virus was passed in the control group as readily as it was in the  fish stored in the fishermen's livewells. Any handling during the weighing process was determined to be a non issue as far as the spread of disease was concerned. The control group fish suffered the same mortality rate as the "livewell" fish. I wish I could remember the numbers, but it was extremely high for both groups. Something in the order of 70%. The university group conducting the experiment will be doing some follow up tests.

The bottom line is, LMBV spreads very rapidly when the fish are confined. If further testing proves this to be true, some changes are in order. Unless this problem is ignored, tournament weighing procedures will have to be completely re-designed. The weigh-in may have to just go away.

I realize that is a dramatic statement. But the alternative is worse. Not only are most of the fish captured going to die, if this study proves to be correct, but they are going to live long enough to pass it on.

I'm not a biologist, so I don't know what the overall effect of this disease is on the bass population. Is this a nation-wide problem? Or, is it regional in nature? Could having infected fish in our livewells spread this virus from one lake to another? These are some questions I have not seen answered.

I'm going to locate the results of the experiment and see what it has to say.

Not trying to PO any tournament anglers here. I'm just interested in this issue.



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TPWD have done enough tests.    Their finding do not agree with all that is being posted.     Numerous species of fish can transmit the virus.    Not just a livewell problem or captivity isssue.

What I saw in 1999 on Lake Fork was not due to any tournaments.    First off, on Fork, you could not keep a fish that was 14-21 inches, and only one above 21 inches then.

The majority of fish killed were in the slot and up.    It was not the 14-18 inch fish, the normal tourney stringer size.    These bass, that numbered up in the thousands was 7,8,9,10's and up.   Some smaller bass, but compared to the toads, we lost around 10,000 bass 7 lbs and up, and that killed this Trophy fishery.    It was down played by locals, after all, thats the only living they have.

You figure any tourneys on Fork, the majority of livewell fish would at least be 4 fish under 14 inches, and the LMBV attack on Fork had nothing to do with little fish that would have been caught in Tourneys.

I do think all anglers should clean their livewells out with bleach or other approved agent after each use to kill any bacteria's.    Its not just tournament anglers who use livewells, so all anglers should do their parts.

Unless there is some new breaking news, LMBV still leaves biologists to scratch their heads.     They have figured how to identify it, and test for it, but haven't figured out how to stop it or where it will re-appear.   So far, each lake to have had the one time virus has not seen it show back up


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I was going to make the same suggestion as to cleaning livewells in between tournaments and outings... thank you for making that post.  Cleaning livewells will not only help decrease the likelihood  of spreading LMBV from lake to lake, but it will also decrease the likelihood of spreading non-native invasive plant species or other diseases from lake to lake.

I'm anxious to see what follow-up studies on the livewell spread of LMBV yield.

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You have posted a good question. It is true that the LMBV can be spread in livewells. I emphasis

the word, "can", because research has proven that there are livewell conditions that can promote

the spread of the virus. Research has proven that the virus can be spread when livewell temps

exceed 78F. Bass were noted to have a much more severe disease reponse when temps reached

84F. In 2003 the FWC (Florida Fish and Wildlife Conservation Commission) obtained blood samples

from 231 largemouth bass from 9 Florida lakes. Fourty four percent of these bass tested positive,

showing that they had been exposed to the virus and had developed antibodies against it. In otherwords,

their immune system effectively dealt with the virus by producing antibodies. The finding was

VERY significant, because it demonstrates that bass are becoming immune.

Dr. Jack Gaskin of the University of Florida conducted a study right after the FWC sampling, where

98 largemouth bass were innoculated with the LMBV. The results were that that ALL of the virus

challenged bass developed antibodies to the virus. The research mirrors the the results found in the

wild. Ongoing studies have shown that stress reduces the immune response in fish, especially in

hot weather.

For almost 13 years, I have studied the effects of stress hormones called cortisols in vertebrates.

The study became a matter of life and death for me, when I was diagnosed with the most deadly

strain of HCV (Hepatitis C Virus), that I recieved from a blood transfusion in 1980. Through what

can be termed as, "better living", I have been able to keep my OWN cortisol down to VERY LOW

LEVELS. The HCV viral load in my own body has been DRASTICALLY slowed, allowing my liver cells

to regenerate before life threatening damage occurs. I have now applied my research with human

viruses, cortisols, and immune responses to fish.

Fish need healthy ecosystems in order to properly develop healthy immune and reproductive systems.

State and Federal DNR agencies have made great strides in the last few years to address ecosystem

issues such as habitat improvement and water quality improvement. It is an ongoing process. Tournament anglers can help by properly handling their fish, and providing adequate livewell conditions

for their catch. I believe that I posted the entire study that you are referring to on this forum. The

study was VERY flawed IMO, but did show high mortality rates at elevated temperatures. They

did not sample an adequate amount of bass for the LMBV in the study. Most of the bass died from

bacterial infections, due to elevated water temps and overcrowding in pens and raceways.

To answer your questions, the overall effects of the LMBV have GREATLY diminished for the bass

population. Yes, many viruses can be spread from one lake to another. It is very important for

tournament anglers to disinfect their livewells after EVERY tournament to prevent the spread of

invasive species and pathogens. We are working on a livewell and boat disinfectant that is currently

used in hospitals and some aquaculture facilities to kill various pathogens including viruses, without

the possibility of residual harm to the fish. Solutions of bleach can produce chlorine toxicity to fish

if livewells and equipment are not rinsed WELL. Also, bleach solutions can cause respiratory problems

in humans if fumes are inhaled in a confined area, such as a garage or storage facility.

The LMBV does not pose a great threat to the largemouth bass population, but there may be new

emerging viruses on the horizon like the newly discovered VHS (Viral Hemorragic Septicemia) on

the Great Lakes that could significantly impact the fisheries. Hopefully, this information will help.

IMO, healthy ecosystems are key to the survival of the fisheries, and tournament anglers help to


support is VITAL, the benefits that tournament anglers provide to the resources GREATLY outweigh

ANY potential harm!

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Ghoti, Those are some great questions. It really opened my eyes to the responsiblity we have as anglers to protect our fish from this virus.

Lane, WOW!!! Once again you amaze me with your information packed answers. Thanks to you and Toni for all you have done for our fish.

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