| Author |
Message |
    
mel
Neonate
Username: Guisburn
Post Number: 10
Registered: 07-2007
| | Posted on Thursday, June 03, 2010 - 11:21 am: | 
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Need some help here....I am concerned that in error my vet injected stallion for EHV1 4, instead of taking a blood sample for EVA clearance. Once informed of her mistake she went on to take the blood sample, but I have heard that the EHV1.4 can cause problems with the test?? The stallion has not left station for 2 years and no other mares have visited, but I have been on the net and some articles are making me really worried. |
Jos
Board Administrator
Username: Admin
Post Number: 2885
Registered: 10-1999
| | Posted on Thursday, June 03, 2010 - 01:02 pm: |
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EHV and EVA are different viruses, so they should not cross-test. |
mel
Nursing Foal
Username: Guisburn
Post Number: 11
Registered: 07-2007
| | Posted on Thursday, June 03, 2010 - 01:20 pm: |
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The info I have is in Vet speak so it may mean more to you...
Evidence that use of an inactivated equine herpesvirus vaccine induces serum cytotoxicity afecting the equine arteritis virus neutralisation test. Animal Health Trust, Suffolk UK
...several laboratories worldwide have recently exerienced problems relating to serum cytotoxicity with the EVA neutralisation test (VN) when using Office International de Epizooties (OE) reference laboratory prescribed rabbit kidney (RK-13) indicator cells. Cytotoxicity can be mistaken for viral cytopathic effect and las led to increasing difficulties in test interpretation, consequently causing disruption to both equine breeding and disease surveillance......
The stallion has 2 yearlings and a foal this year and has not left the yard for over 2 years during which he has had 2 clears. No outside mares have visited and no other horse has come in. |
Jos
Board Administrator
Username: Admin
Post Number: 2886
Registered: 10-1999
| | Posted on Thursday, June 03, 2010 - 01:46 pm: |
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It is somewhat of a moot point in all probability, as certainly if - and it is a large "if" - there were a problem with cross reactivity, almost certainly they would retest and you would have to have two "if's" kick into gear consecutively (granted still not impossible, but increasing the odds of unlikely). They could also do a PCR test which would most likely yield a different result owing to different testing techniques.
The ultimate factor is though that even if the stallion tested sero-positive (i.e. antibody-positive in blood) unless he had been actively infected with EAV (the virus) he is not going to test positive for viral presence in the semen. Consequently, with the outside exception of a situation where the stallion (or his semen) was going to be exported to one of the handful of [backward] countries that do not allow seropositive stallions in regardless of semen status, it's not going to be an issue. "Seropositive" and "semen positive" are two very different things! |
mel
Nursing Foal
Username: Guisburn
Post Number: 12
Registered: 07-2007
| | Posted on Thursday, June 03, 2010 - 02:42 pm: |
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Thanks Jos, just had call, positive....sounds like semen testing will be needed which will be fun as he only gets his one wife a year, and the bill will be huge I am told , to collect and test twice. I just cant understand how this has happened??? |
mel
Nursing Foal
Username: Guisburn
Post Number: 13
Registered: 07-2007
| | Posted on Friday, June 04, 2010 - 12:48 am: |
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What is the PCR test? |
Jos
Board Administrator
Username: Admin
Post Number: 2888
Registered: 10-1999
| | Posted on Saturday, June 05, 2010 - 04:13 am: |
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There is a useful paper discussing testing EAV techniques to be found here (follow that link). It is a 2003 publication, so there may be some newer data somewhere, but it's a good start for you. |
