Yume Koi Has Been Hit With Khv

[koifishgirl]

Ok I used wrong word but I was talking about breeders. I understand that Mike is a breeder that sell's to dealers. Dont breeders sell and by from each other from time to time?

[B.Scott]

Mike is a dealer that buys from breeders and sells on to other dealers.
Yes, Breeders do exchange alot of fish back and forth for a varyity of reasons. Their business depends on this.Up to now QT isn't something they have bothererd much with. But even with QT the protocol being recomended to them by their associations is inadequate. Standard practice it to heat to 24*C and add a naive fish. If the fish don't die it should be ok. Unfortunately without repeated temperature stressing with several cycles between 15*C and 24*C you will often not see KHV. At this point it is becoming doubtful if even this will be enough as Mr.Showa above demonstrates. This fish is highly infected and still not showing and illness.

B.Scott

[bekko]

Nice posts B.Scott. Thank you.

-steveh op

[Jagger]

Interesting discussion.

Quote: Originally Posted by MikeM If you are dealing with $1,000 koi, the $10 cost is easy. But it sure doesn't work for the many thousands of tosai exported to retail for $30 or less. And, not so easily passed on even for nisai sold to retail for $150.

Mike,is it still a thousand dollar fish without an ELISA test certificate?

Ultimately the price will be borne buy the buyer,but surely the price for the test would drop if it gets used anything anywhere near as often as it should.

[MikeM]

Jagger: Yes, I think the cost would come down, but enough to be used on all those tosai? .... At present, I think we are heading toward a type of class distinction within the hobby quite unlike what we are accustomed to seeing. One class will be composed of those who acquire inexpensive koi and are continually at risk of KHV. The other class will be composed of those who acquire expensive koi that have been rigorously protected from exposure, tested and vaccinated. Over time, the hobby declines. Hopefully we avoid this scenario through research and education. I think we ultimately will. However, I see posts nearly every week on one board or another that make clear that only a small minority of koikeepers have bothered to learn even the basics about this disease. That is the very sad and scary part of the way things are.

[bekko]

Insurance companies know the probabilities that something bad will happen and use that information to determine the cost of a policy so they can still make a profit. You buy insurance for your house because you cannot afford to loose it - even though the insurance company has the odds stacked against you. You do not buy the extended service warranty for an alarm clock because if it breaks you are able to deal with it. An ELISA test is an insurance policy.

-stevehopki

[PapaBear]

Quote: Originally Posted by bekko About a year ago on Koi Bito, Ray Jordan posted this about PCR and ELISA: "Naive Koi (never exposed) PCR test negative/Elisa test negative Exposed Koi - Naturally immune will not get KHV (could become a carrier) PCR negative/ELisa Negative Infected and awaiting optimal temperture/conditions to develop KHV PCR Negative/Elisa test negative Infected and has developed KHV disease (majority will die) PCR test positive/Elisa test negative Infected but will survive (could become carrier) PCR test positive/Elisa test negative KHV Survivors - Infected with KHV but survived (could become carrier) PCR negative/Elisa Test positive Placing all new koi in a strict quarantine at 72-78F for 3-4 weeks and adding a "canary" koi to test for carriers able to pass on KHV infection is the only way to currently protect your koi collection. Can anyone prove that this is 100% perfect guarantee to keep KHV out of your ponds, No! But, experts do agree that following a strict quarantine with perfect biosecurity at optimal temperture and adding a "canary" koi then it would be very very very unlikely to not discover KHV infected koi during proper quarantine." ...

According to the above testing criteria, the Elisa test is USELESS at most stages of KHV development, so how to test and when is a key issue. A Koi becoming exposed, infected, but either naturally immune or temperature lowered after exposure will not develop antibodies. Be it a $100,000 future champion or a $10 crapagoi, it is undetecable by the Elisa test. Naturally immune Koi won't even test positive by the PCR method.
This being the case, any Koi to be tested absolutely must be brought up to outbreak temperatures and HELD there with canaries for a period of time adequate to infect the canaries with certainty.
Tested Koi would then need to be held in segregated isolation with a paper trail until the test results came back. That kind of biosecurity for $10 Koi just doesn't seem likely...

[KoiCop]

good points. Thanks for reminding us all.

[KoiCop]

Autumn 2006 Koi, and other news...
10th January 2007



In referance to Koi imported in Autumn 2006, each and every Koi that we will be offering for sale, and every customers Koi has been blood sampled, and we are awaiting the results from CEFAS. After the results come back, we will temperature cycle them. In the event of any positives coming back, we will remove these Koi, and temperature cycle. In the event of any positives being present, all Koi will be retested after temperature cycling, for customers peace of mind. The picture shows Koi being anaethetised for blood sampling. Each time we photograph a Koi, the digital camera assigns an image number to the photo. This number is also written on the blood collection tube, and hence, and result bears this number. This makes for an accurate identification of any test result, and the Koi concerned.

As for pre-existing Koi here... each and every Koi has been blood tested twice, and the results and data can be viewed upon request. These Koi were also temperature cycled in between the blood samples being taken. It is my belief, that these particular Koi are the safest Koi that will ever be offered for sale... anywhere!

As for the one anti-body positive Koi that we have had here since we commenced blood sampling in July... we tried to cause an outbreak with this Koi, using naive Tosai, to no avail. This Koi, along with four Koi from customers ponds (not supplied by us, and not cross infected), have gone to CEFAS for research purposes.

It seems that the data from our 700 ELISA tests carried out to date, will not be going to waste. We are currently databasing all of the Koi tested, the data of which will be used closely with CEFAS for research purposes, and also for the purpose of the ELISA test being 'validated', so that it will be recognised internationally as a reliable method of testing. With any hope, other countries will hopefully end up using this test method to eradicate this virus before it's too late. At present, this is the only test available that can identify Koi that pose a threat to carp populations. Even in Japan, the only tests available, are PCR, and Loopamp. Both of these test methods will only detect Koi that have virus DNA present, which can only be detected when the Koi are actively shedding the virus. Please note, that any breeders, and dealers (apart from ourselves) will be kept confidential by us in respect of all of this data. I'm sorry if some people will feel that we aren't being completely open with the information, but my feeling is that anyone inflicted with this virus, is a victim, whether dealer, breeder, or hobbiest.

In ref to the ELISA test... It has been brought to my attention, that I have been criticised for destroying Koi that may have been completely safe. My feelings about this are simple... The ELISA test simply tests for antibodies. If a Koi hasn't ever been exposed to the virus, it will test negative for antibodies. However, if a Koi tests positive, it basically means that the Koi has seen the virus, or in laymans terms, 'survived' the virus. This being the case, some Koi will become carriers, and some will completely destroy the virus and not be carriers. My thoughts are this are as follows... Theory is, that a Koi that is anti-body positive long after exposure, is most likely as carrier. However, consider anti-body counts as a war between two armies... If a Koi is a KHV carrier, it will have anti-bodies. If it has a strong anti-body count, it can be argued that the army of good troops is far outnumbering the bad side. So, in the event of the virus trying to replicate... the anti bodies are plentiful, and at the ready, so will perhaps ambush every virus DNA that comes out of hiding, and hence keeping the Koi from shedding virus into the water. It is possible that such a Koi can have such a responsive immune system, that the virus will always be kept at bay. But, imagine the Koi getting old, and perhaps suffering some kind of internal organ failure/infection? What happens if the immune system puts all it's energy into fighting off such an infection? is there a chance that such a Koi will then fall prey to KHV, and hence release virus into the water? A KHV carrier will test negative by PCR test, for KHV. But, in the event of the Koi releasing KHV and causing an outbreak, it will test positive by PCR. However, after the outbreak has finished, the same Koi will test negative again. Negative PCR means no virus DNA present in the blood, and hence no possibility of shedding virus. The virus in effect, is hiding in the nervous system, waiting for an opportune moment to cause an outbreak.
Going back to the subject of destroying ELISA (anti-body) positive Koi... Each and every one of these Koi has to be considered a risk. You and I, and indeed any biologist, cannot deem any of these Koi as being safe. It is impossible to look at one of these Koi and say, "Oh, I am certain that this one is safe! How can this Koi possibly be a KHV carrier?" Just because you've temperature ramped this Koi, doesn't mean it's safe... period! As a dealer, the only responsible thing to do, is destroy all AB positive Koi. I simply cannot afford to take a chance on keeping such a Koi. As the top guys at CEFAS said... A carrier cannot shed virus without causing an outbreak. So, remove a potential carrier, and crank up the temp to 24c. If virus has been shed, and outbreak will happen. Repeat anti-body testing, will confirm that none of the cohabitants have seen any virus. I hope this makes some logical sense to all who read this.

I will be at the All Japan Show, so will look forward to seeing any familier faces there!

Best regards,

Mike

Source: http://www.yumekoi.com/index.php

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Wonder whether Ray Jordan (or Spike Cover) have any comments as to the science in this post?

[B.Scott]

I've asked Spike if he has time for a responce. Lets see what happens.

B.Scott