Running up Hill

In most situations the more effort you put in to control something such as pneumonia or mastitis the chances are that you will see a reduction in the numbers of animals that you have to treat and your animals will be healthier. Usually if you are trying to control something by testing for a disease and the incidence continues to increase you would seek a different way to halt the spread of infection. Sadly none of this applies to the most serious animal disease that we have in this country Bovine Tuberculosis. Somehow it seems the more we test the more animals we find affected. There have been blips before in the ever rising number of cattle affected by tuberculosis, never before have there been so many new cases in our area. Two hundred and sixty nine new farms in Shropshire so far this year, the average numbers of cattle that are reacting on farms is also rising.

Random Appearance

There does not seem to be any particular pattern revealing which farms are vulnerable to developing the infection. We see it just as often on farms that are self contained and buy in few if any replacements as we do on farms that are constantly bringing in mature stock. It will occur just as often on farms that have cattle neighbouring them as on holdings that are isolated from other cattle. One of the most alarming things is that numbers of young animals under the age of twenty four months that are affected now. This was virtually unheard of twenty years ago. As far as I can determine here in Shropshire where most farms are tested at least annually, pre movement testing has had little impact on the spread of the disease. Some of the reactors we have found have been pre movement tested within the past few months. They would not have had time to react to the test before leaving the farm. It would seem that the gamma interferon blood test is not going to come into general use. It is an expensive test to run, it is very sensitive and the samples must be kept at blood temperature until they are delivered to the laboratory on the same day for immediate testing. It has been found that on some farms the test has been giving positive results for animals that show no signs of disease. It does have a place for deciding the fate of inconclusive animals, but even here the test results need to be interpreted with caution.

The TB Cycle

If you have cattle that go out to grass sooner of later you will have problems with TB. Over the years we have tried to determine the pattern of which farms get the infection and which ones stay clear and might have valuable management practices that could help others. I have come to the conclusion that there is no pattern the disease seems to be active in the badger population for four or five years before it will reduce for three or four years and then come back again. The thing to do is to work out how you will be able to cope when you are put under movement restrictions.

Plan a Coping Strategy

Farms are most vulnerable if you do not finish fattening stock, or if you sell dairy bull calves or newly calved heifers. Will there be somewhere to rear the extra calves? Will there be room in the dairy herd to accommodate the extra heifers that calve. You might need to pension off some of the older cows to fit them in. In theory calves from farms under restrictions can go to specialist rearing units and be tested there regularly. In practice this is difficult to arrange and you will be severely penalised over the value of the animals. It is better to rear them yourself if you can and sell them as strong stores when the movement restrictions have been lifted.

The Vaccine is Back!

Finally after four weeks extra waiting Bluetongue vaccine is being supplied to farms again, two million doses were sent out earlier this week to Cornwall and that area in the South East of Wales. The hold up had something to do with the pH of the vaccine that had an effect on the colour of the injection. Hopefully the vaccine supply will be more reliable now. Veterinary Surgeons in Germany, Belgium and France have been busy vaccinating cattle and sheep as vaccination is compulsory in those countries, the aim is that all stock will be fully vaccinated by the end of the year. With the scheme we have here it will be difficult to monitor the vaccine uptake and each delay in the supply chain will have an effect on the overall uptake. So far the disease has been slow to get active this year. The danger is that when it does start it might crop up over a wide area in a short period of time.

Name Changes and Stock Deletions

For some reason known only to themselves Intervet has decided to change the name of their milking cow tube Cephaguard LC to Cobactan MC. Every thing else about the drug remains the same. Cephaguard LC has only been available for a short time and it has always been known as Cobactan MC in other countries so it is not clear why they decided to launch it by a different name here. Eventually the name change will have to be made in all of the Herd Health Plans. At the same time Intervet have stopped making Cephaguard Dry Cow, Cephaguard injection and Mycophyt. All of these were useful products. Let us hope that Cobactan MC will stay with us for some time now it has changed its name.

Avian Influenza

All of the movement restrictions have now been lifted from the farms in Oxfordshire where they had the latest Influenza Outbreak. It has been confined to one farm again and the suspicion is that it could have been a common strain of the virus that managed to mutate and become significantly more pathogenic for some reason. The virus has not been detected from wild birds in the area. If you keep any number of poultry it would be wise to register them with DEFRA so that they can send you text messages as soon as Avian Influenza is diagnosed. That way you will not miss any information if it should turn up in Shropshire. It is not easy to keep birds inside if they have been used to their freedom. The risk is small as long as you know where the disease outbreaks are.

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