Unfortunately one of our in calf cows (about 2 weeks 'till calving) went down as an Inconclusive on her TB test last Friday.
I have had one particular cow react as an IR a few times and she has always gone clear 60 days later.This year she is fine and a different cow is now an IR.
It has been suggested to me by a a farmer friend that I should worm the cows now and it may help with our next test result.
My vet advised me last year that I only needed to worm the youngsters and that the adult cattle didn't need worming.
He gave one cow an injection for fluke as she was looking a bit ropey , incidently it is that very cow who is now an IR
The last time that I wormed the whole herd was 2 years ago with Ivomec.
Anyone got any ideas / suggestions / opinions etc etc ?
Thanks
Dominic
TB testing and worming
I thought I was told by a young vet a few years ago that fluke wormer had caused IR problems in herds but when I mentioned this to a senior in the group he said I'd got it wrong and it was fluke infection which causes the problem. Frankly I don't know what to believe but the condition of my herd does not suggest that it is fluke ridden, neither do the dung tests which I do occasionally.
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Duncan MacIntyre
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For many years there have been stories of certain drugs influencing tests. Being a fairly straightforward sort of person I have never had any interest in doing things which would influence the results. Some of these fiddles have revolved round getting things to fail rather than pass, so beware that attempts to influence results may not all operate in favour of beasts passing the test. Some well known worming drugs for example can stimulate the immune system, and I can see no way they will do anything but increase reactions rather than reduce them. What I cannot see them doing is making animals react which have no reaction to tuberculin in the first place, or to completely prevent a reaction which should have shown.
My understanding of non specific inconclusive reactions is that the animal will have at some time been exposed to bacteria which produce similar but not identical reactions to the real tuberculosis infection, so there is some reaction to the injected tuberculin. At the end of the day you have to be sure or as sure as is possible, that you have not missed any genuine reactors - it is worth sacrificing a certain number of false positives if need be to be sure you are free of the disease. Sadly the tests are not 100% but in fairness to DEFRA they have spent a lot of time and money looking at other tests for TB.
Duncan
My understanding of non specific inconclusive reactions is that the animal will have at some time been exposed to bacteria which produce similar but not identical reactions to the real tuberculosis infection, so there is some reaction to the injected tuberculin. At the end of the day you have to be sure or as sure as is possible, that you have not missed any genuine reactors - it is worth sacrificing a certain number of false positives if need be to be sure you are free of the disease. Sadly the tests are not 100% but in fairness to DEFRA they have spent a lot of time and money looking at other tests for TB.
Duncan
Duncan MacIntyre
Burnside Dexters 00316
Burnside
Ascog
Isle of Bute
Burnside Dexters 00316
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Isle of Bute
Thankyou Duncan
I hadn't thought of it in that way of trying to affect the result.
I guess we'll just wait and see what happens.
Another thing though , if she is a reactor , will her calf automatically be infected ? If she has calved by the next test ( I jolly well hope so ) will her calf be taken automatically or tested in it's own right ?
I hadn't thought of it in that way of trying to affect the result.
I guess we'll just wait and see what happens.
Another thing though , if she is a reactor , will her calf automatically be infected ? If she has calved by the next test ( I jolly well hope so ) will her calf be taken automatically or tested in it's own right ?
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Duncan MacIntyre
- Posts: 2372
- Joined: Tue Mar 30, 2004 12:38 am
- Location: Isle of Bute, Scotland, UK
Dominic,
I do hope that your cow passes its retest. Please do discuss the calf with your own vet and/or the Animal Health vets. I am posting this from the house so have not got the manual by my side, but my understanding is that the calf would not be taken automatically but would be tested as an individual.If a cow were infected with TB I think the most likely route of infection to a calf would be by breathing or swallowing infected material from the cow, which could be by coughing or nasal discharge, urine, faeces, saliva and of course milk. I think these are much more likely than being infected via the placenta before birth. So if you have a cow which is awaiting retest which calves, it might make sense if you wish to preserve her breeding line to remove the calf at birth, give it colostrum from a known healthy cow, and hand rear it in isolation. It would need to be isolated from the rest of the herd as well as the cow, because I think the ministry vets would want to test it but I am not sure of the age at which they would do this. . Just a suggestion, and as I say I have not got the official TB testing manual to hand so cannot gaurantee that my memory of the regs is absolultely right.
Duncan
I do hope that your cow passes its retest. Please do discuss the calf with your own vet and/or the Animal Health vets. I am posting this from the house so have not got the manual by my side, but my understanding is that the calf would not be taken automatically but would be tested as an individual.If a cow were infected with TB I think the most likely route of infection to a calf would be by breathing or swallowing infected material from the cow, which could be by coughing or nasal discharge, urine, faeces, saliva and of course milk. I think these are much more likely than being infected via the placenta before birth. So if you have a cow which is awaiting retest which calves, it might make sense if you wish to preserve her breeding line to remove the calf at birth, give it colostrum from a known healthy cow, and hand rear it in isolation. It would need to be isolated from the rest of the herd as well as the cow, because I think the ministry vets would want to test it but I am not sure of the age at which they would do this. . Just a suggestion, and as I say I have not got the official TB testing manual to hand so cannot gaurantee that my memory of the regs is absolultely right.
Duncan
Duncan MacIntyre
Burnside Dexters 00316
Burnside
Ascog
Isle of Bute
Burnside Dexters 00316
Burnside
Ascog
Isle of Bute
If there are reactors in a herd it was my experience that every animal in that group had to go. In addition the severe test is applied which drags more up into reactor or IR status. However, it is never wise to 'second guess' these blessed tests Dominic once you know what you have there is time to worry about it then. Good luck.
Over the past 10 years we have noticed if we are unlucky enough to have an inconclusive on our TB test it is always a cow who is very near calving ..just calved..or just been weaned,we are sure that the hormonal upheaval at these times will trigger a reaction,this idea has been supported by our Vet who has also trained in alternative medicine,we now arrange all such traumatic events to happen well away from testing time,and Im almost afraid to say it without touching wood ,crossing fingers , and throwing salt over my left shoulder,but so far so good,we are in a TB hot spot so its yearly testing for us. Sue PS for some reason the site has refused to recognise the name of my lovely red bull Forest Blaze so we are now posting under the name of the farm sue