Badgers in the bTB firing line

Peter King, Executive Committee Chair at the European Livestock Association, NFU Director, Anthony Gibson, and Animal Health and Welfare Minister Ben Bradshaw, are among those Neil Davey speaks with to find out.

Despite efforts to deal with Bovine tuberculosis (bTB) spanning decades, the disease has re-emerged and is today one of the most significant animal health problems confronting the UK’s farming industry. But while it presents a serious threat to both cattle and the agriculture sector, it has been bTB’s impact on another animal altogether – the common badger – that has brought the debate on how to tackle the problem to the fore.

As many as 40 percent of dairy cattle in Britain were infected with the bacterium Mycobacterium bovis in the 1930s, with approximately 2000 human deaths per annum thought to have resulted from being in close contact with infected animals or drinking contaminated milk. However, a campaign of milk pasteurisation and testing animals using the tuberculin skin test brought the outbreak under control, as infected cattle were rounded up and culled.

Nevertheless, despite being virtually eradicated decades ago, bTB has persisted and incidences of the virus are once again rising, particularly in Wales and the Southwest and West Midlands of England. The Department for Environment, Food and Rural Affairs (DEFRA) estimates that three percent of the national herd is now affected by bTB and last year 3653 new herd incidents were recorded in Great Britain, amounting to a nine percent increase on 2004.

The National Farmers Union (NFU) has warned that those regions worst hit could lose most of their beef and dairy farms if the threat of bTB continues, with estimates suggesting that as many as 17 percent of cattle farms in some regions were under restrictions in February this year because of positive TB tests. Peter King, Executive Committee Chair at the European Livestock Association emphasises the seriousness of the situation.

“When a farm is closed down for a time due to a possible TB reactor(s), he is not able to trade for a period of time,” he explains. “That is bad enough for a big commercial enterprise that is producing normal commercial beef. But for a farmer who has got a pedigree/purebred herd of cattle with a premium market for the specialist beef he produces, it could actually impact seriously upon the viability of his business and prevent a very high quality product from reaching the discerning consumer.”

In response to this worsening situation, just before Christmas, DEFRA announced a number of measures to tackle this issue in England. This included the introduction of a new compensation scheme for farmers whose cattle are affected by bTB based on table valuations; the introduction of a new pre-movement testing regime in cattle aged over 15 months moving herds that require testing every one or two years; and a consultation on the principle and method of badger culling as a measure to control bTB in cattle in high incidence areas of England.

Badgers and bTB

Badgers have long been suspected of being a source of bTB infection. DEFRA (then MAFF) started to kill badgers as a means of controlling the disease as long ago as 1975, following the discovery of a badger that tested positive for bTB. Between 1975 and 1995 it was estimated that some 30,000 badgers were killed. Certainly evidence points to badgers contributing to the problem in some way.

While other wildlife species are also susceptible to M. bovis, infections in these species are not as common as in badgers. Meanwhile, various surveys suggest that infected badgers develop TB and produce larger numbers of bacteria than other animals, while infected badgers have been shown to transmit infection to cattle under experimental conditions – although the finding has been questioned. Nonetheless, the findings were deemed sufficient in the 1970s to initiate a cull in areas where bTB was a problem, and there were reportedly some subsequent drops in disease levels in cattle at several sites.

However, the extent of the badgers’ contribution has always been a cause of great debate. Even a £35 million government-funded review of the evidence for a link between badgers and bTB chaired by Professor John Krebs concluded that, although there was convincing evidence that badgers were a source of infection for cattle, the proportion of cases in cattle that were due to badgers could not be calculated. With infection continuing to rise, reactive culling was suspended in 2003. But with DEFRA once again hosting a consultation on TB plans, ministers are once again considering a badger cull – news that has been warmly received by the NFU.

Research by the NFU recently revealed that more than 94 percent of farmers in the stricken South West region support the idea of a badger cull as a way of controlling bovine TB. South West NFU Director, Anthony Gibson, is philosophical about the badger cull debate. "In an ideal world, 30,000 cattle would not be prematurely slaughtered each year and we would not be talking about culling badgers," he says. "But the facts of the matter are that we will never control bTB in either cattle or wildlife if we do not tackle the reservoir of the disease in badgers, and the sooner the government accepts that harsh reality, and takes the action that it implies, the sooner we can stem the insidious spread of disease through our countryside and farms."?

Not clear cut

Nevertheless, there are up in arms at the prospect of a badger cull and maintain it is extraordinary that ministers are considering such action. Organisations such as the Badger Coalition, for instance, maintain that badgers are being scapegoated by DEFRA to placate the farming sector, whose intensive production systems are largely to blame for the increasing levels of bTB in cattle.

It is similarly suggested that the recent spread in the virus is connected with the BSE crisis and Foot and Mouth Disease (FMD) outbreak in recent years, specifically that with cattle being moved around the country in much greater numbers to replace cattle that were culled, the potential for the spread of TB was much greater. Certainly all parties concede that the pre-movement testing regime has been sub-par during and since the outbreaks – a fact acknowledged by DEFRA’s announcement that it would be introducing a new pre-movement testing regime.

Furthermore, research by the Royal Society has also raised doubts about whether a cull would effective regardless of the extent of the badger’s contribution. “The case for badger culling is not clear cut,” says Professor David Read, Vice President of the Royal Society. “The introduction of culling could result in an increase or a decrease of bTB. Which of these will predominate is likely to depend upon the details of the culling regime adopted. There is some evidence to suggest that culling would need to occur over at least 300km2 to result in a net decrease in badger to cattle TB transmission rates. Culling badgers over such a large area would require serious consideration of the impact on the conservation status of badgers.”??

Badger Trust spokesman Trevor Lawson emphasises that politicians from all parties have previously promised that bTB strategy would be based on the outcomes of scientific research. “The science is now as sound as we are likely to get,” he highlights. “There is universal agreement in the scientific community that badger culling will not bring bovine TB under control unless badgers are virtually exterminated. The public is supportive of farmers, but not at any price – and eradication on that scale is not publicly acceptable. Nor is it practical or cost-effective to implement.”

Animal Health and Welfare Minister Ben Bradshaw recently acknowledged the nature of the problem in the Commons. “The international experience suggests that if we leave the reservoir in wildlife untouched it will prevent us from containing and eradicating bovine TB,” he said. “We have made that perfectly clear. But we face a challenge in finalising a practicable cost-effective system of culling that is scientifically sustainable in the long-term.”

Viable methods

The Royal Society has, however, highlighted other viable methods to reduce bTB in place of a badger cull. The introduction of ‘biosecurity’ measures is one such example, aimed at reducing badger and cattle contact (possibly by ensuring herds are on farms with hedges) and reducing cattle-to-cattle contact by improving farming conditions, particularly during cattle movement. But there are also major calls across the entire stakeholder spectrum for better testing.

It is widely accepted that the TB test used on cattle is not completely accurate, and that some cattle with TB are not detected by the test and so escape slaughter. With the increased movement of cattle across the UK ensuring that these animals can transmit the disease to other cattle, it is argued that bTB will never be wiped out until better diagnostic method is implemented.

"There is clear scientific evidence that cattle-based TB controls can have a huge effect on reducing bovine TB,” says Lawson. “In Northern Ireland, the disease has been reduced by 40 percent in just one year, simply through better TB testing. That is the intelligent, sound and cost-effective approach to TB control. The big question now is whether politicians from all political parties will stick to their promises and work together to implement it."??

King highlights how the present system is also further damaging the industry.
“The technology exists to provide more accurate testing,” he says. “The present testing system in the UK is widely acknowledged to be inaccurate – it’s like taking a shotgun to the problem and hoping they hit something. I will mention one farmer that had six pure pedigree Herefords killed because they reacted to the UK TB test. When they hung them up and studied them, none of them showed any clinical evidence whatsoever of having TB. That farmer has lost those animals forever from a herd that has been established for 50-60 years, the slaughtered cattle included rare bloodlines. DEFRA now have no credibility with him. And that is a significant factor, because if they want support and cooperation from producers to beat the problem, they need a credible way of going about it. Right now, it is a national joke as well as a national disgrace.”

Culling consultation

While the short-term situation continues to worsen, long-term efforts by DEFRA continue to focus on the possibility of a vaccine for both cattle and badgers. “The department has invested more than £10 million in vaccine research over the last seven years,” says DEFRA spokesman Matt Conway. “A field trial has been approved for a TB vaccine for badgers and the initial survey work required to underpin the trial is almost complete. Work on improved diagnostics and oral delivery of vaccine in badgers is continuing. In relation to cattle vaccine our laboratories began work in January on new vaccine candidates and delivery protocols in a natural transmission study.”

The European Livestock Association’s King supports the vaccine campaign, but is realistic about the short-term measures he believes will still be required. “We at ELA are very pro-vaccination although there are suggestions it will take 20-30 years, therefore in the short-term we recognise that there may be a need to carry out controlled culling of a certain number of badgers in a certain number of places,” he says. “It must be emphasised that that is for the benefit of the health of the badger population as well as cattle. This needs to be accepted. Farmers like badgers and would never support needless control of wild species. Rare cattle breeds are particularly at risk from the increasing prevalence of TB due to their numerical situation.”

It presently costs Britain an estimated £90 million a year to tackle bTB and the NFU forecasts that this will more than double in the next five years. Pre-movement testing was implemented in England in March and the new compensation system in February. The badger culling consultation closed in March, with the government having received more than 10,000 submissions.
Whilst farmers’ bodies put their weight behind a cull and wildlife groups protest against the proposed slaughter, the government is closely considering its next move. But the final decision will inevitably cause consternation amongst some.

“We will continue working with our stakeholders to reduce bovine TB – through rigorous cattle-based controls including pre-movement testing – and we will continue to press ahead with our wide-ranging research programme,” concludes Conway. “In relation to badger culling, the decision the government now has to make is not a simple one. We have received tens of thousands responses to our consultation. We are now studying these responses along with all the evidence available to us, including scientific evidence. We will make a decision in due course.”

Other major cattle concerns

bTB isn’t the only problem to afflict cattle, and farmers have had to contend with some alarming outbreaks in recent years.

• Foot and Mouth Disease – a severe, highly communicable disease that affects cattle, pigs, sheep and goats, FMD is characterised by blister-like lesions on the tongue, nose and lips, in the mouth, on the teats and between the toes which then burst, leaving painful ulcers. Although older cattle usually do not die from the infection, they suffer a severe illness that leaves them in a weakened state. They have high fevers, stop eating, give less milk and become lame. The outbreak in the UK in 2001 left thousands of premises infected.

• Bovine Spongioform Encephalopathy – BSE is a progressive degenerative disease that affects the central nervous system of cattle. Its cause is unknown and there is no known treatment for this fatal disease. Typically, it takes from two to eight years from the time of infection for the clinical signs of BSE to appear. BSE-affected animals may display symptoms such as nervousness or aggressive behavior, abnormal posture, lack of coordination and difficulty in rising. The outbreak in Britain in the 90s was believed to have been caused by the inadvertent feeding to cattle of meat and bone meal supplements that were contaminated with an infectious agent.
• Anthrax – A highly infectious, contagious and fatal disease, anthrax can form spores that may persist for many years in the environment. Therefore, most outbreaks occur in areas where animals have previously died of anthrax. Once an outbreak begins in the herd animals may be observed with signs of weakness, fever, excitement followed by depression, difficulty breathing, uncoordinated movements and convulsions. Two cows died of anthrax on a farm in Rhondda Cynon Taf in South Wales in April. It is the first case in Britain since 2002, when a cow died at a farm in Wrexham.