MUCH work has been going on in recent months to collate information from various sources about bovine TB in preparation for a special forum to be held during VetsSouth 2015 in Exeter on 11th February.
The basic premise at the forum is that if members of a veterinary practice were to accept the responsibility for reducing the incidence of bTB within the herds of clients, would veterinary surgeons be confident to establish a local management plan?
This is very different from simply testing the cattle and helping the farmer to overcome the effects of trading restrictions and the loss of production resulting from slaughtered reactors. At the forum, veterinary surgeons will be encouraged to both think and speak for themselves in order to conclude whether they would wish to proceed.
In England there are just over 52,000 cattle herds being tested for reactors and there are approximately 8,000 milk producers. Some of the milk producers will also be beef farmers. In England there are around 5,800 herds that are not bTB-free. So the first question is: which cattle are producing the TB reactors?
Is it the dairy herds or the beef; and is it cows, or yearlings, or youngstock, or in-calf heifers? It was not long ago that all beef for meat was killed by 30 months and many beef herds keep cattle for shorter periods, whereas dairy herds are managed very differently.
The location of the animals is also highly relevant. For the farmer and his veterinary surgeon, being able to target the source of reactors from individual herds would provide the basis for a management plan moving forward.
Four veterinary practices in the south-west have been looking into their records to identify those herds that have been under 60 day testing recently. At this time the findings are unknown but they will be put forward at the forum.
Information on pre-movement failures will also be considered. The source of most bTB failures is available from the DEFRA website and discussions within practices have indicated that there is some uncertainty about the scale of bTB failures from sources other than veterinary testing. Table 1 gives the breakdown of sources of failures for 2013 from six counties.
The sources of failures will be of significance to individual farmers. The bulk of the cattle are slaughtered following veterinary surgeon testing. Placing a veterinary surgeon into the role of bTB control adviser for a farmer is likely to raise an important question from the client.
It is recognised that some herds show one or two reactors on successive tests, then perhaps have a clear 60 day test and then, at the next test, a larger number of failures. The anticipated question concerns the herd being tested clear 60 days ago, but now, two months later, there is a serious incident threatening the future performance of the herd. Has the disease been introduced during the past two months or did the test fail to detect the disease?
Of course, successive herd tests may not include the same animals. A discussion may follow about the value of alternative testing and when to introduce this option.
Fundamentally, it seems necessary to consider whether detecting many reactors indicates the control of the disease for a herd, or the beginning of a more serious future impact. The experience of veterinary surgeons with local conditions will support confidence about the future incidence of disease.
The number of herds that are disease restricted for the six counties (Table 2) indicates the size of the control task. These figures change each month but the table provides an indication of county scale. Practice information would be much more useful. The number of milk producers is also indicated at December 2014. There was a fall of over 400 milk producers in England during 2014 and this monthly trend is continuing. As in other years it is likely that the number of milking cows will remain about the same.
Will the fall in producer numbers be reflected in a fall in the number of restricted herds? Probably not, because a farmer is likely to wait until the herd is unrestricted before selling the cows.
For a veterinary practice to set up an effective local disease control programme the proven way forward will be with herds that have been unrestricted and have now had an annual test failure. The farmer in this situation is more likely to be receptive to the introduction of control options.
The scale of “new incidents” also makes the process much more manageable. For the year 2013, the new incidents’ totals for the six counties are indicated but of greater importance are the numbers of herd monthly incidents, shown over the past year (Table 3).
If the monthly new incidents are spread across each practice in a county, the TB elephant has shrunk considerably. A practice intervention would take place as soon as a herd experiences bTB failure. It is likely that a test at the end of the summer would provide different considerations than a test at the end of the winter. Neighbouring local test results would also become very important.
There are other considerations that veterinary practices may wish to consider and address about bTB control. It is recognised that the immediate control of disease can be targeted but keeping a herd disease-free is more demanding. At the VetsSouth Forum the history of the disease will be examined for future guidance and direct experience with the badger cull in Gloucestershire presented. The role of the badger in the transfer of disease is accepted but the way forward to manage this aspect of control remains a discussion point.
Other relevant issues with the badger, to be considered, are severe weather, flooding of setts, road kill, other dead badgers, pheasants and poisoning. Over the two forum sessions it is intended that veterinary surgeons will discuss their knowledge and experiences and that sufficient information will be produced to enable practices to commence local disease management plans this year.
