#ahvla

This story was published in the North Devon Journal this week.

http://www.northdevonjournal.co.uk/North-Devon-farmer-forced-sell-cattle-herd-bovine/story-20007481-detail/story.html

The arrival of bovine TB after decades clear of the disease has pushed Kentisbury farmers Jim and Valerie Pile into selling most of their cattle herd.

They were shocked in March to find their Higher Week farm under restriction after a positive test.

And even though the farm has gone clear after recent tests Jim has decided to wind down the cattle enterprise and concentrate on his prize-winning Border Leicester sheep.

“I’d been thinking about (reducing) the cattle, but I suppose the TB made our minds up,” he told the Journal.

“It was a shock after all those years. I’ve been keeping cattle since 1970.

“I’ve no idea where it came from. I can’t say it if was badgers, I’m not a scientist. We do have deer up here,” he explained as he checked the remainder of his herd in the fields close to Kentisbury village.

The farm has been in his family since the 1800s, starting off on Jim’s mother’s side.

The couple’s flock of Border Leicester’s is one of the best in the South West, and this year they won the outright breed championship and reserve at Devon County Show with a ewe and a ram as well as best female and best male awards.

Jim and Valerie keep up to 1,000 ewes on 300 acres and have farmed a hundred-strong suckler herd of Hereford and Friesian cattle which has gradually reduced and most were sold at auction by Exmoor Farmers at Cutcombe.

Jim said:“I’m cutting back on the cattle. I might keep a few and buy some calves in the spring. I’ve got to the stage when I don’t want to be calving cows down and the TB situation didn’t help.

“But I’ll do the sheep now, and carry on showing.”

He was pleased with the sale which reachd £1475 for a Hereford Cow with her Limousin calf at foot and others up to £1245 for Hereford X Cows with Limousin X calves at foot.

The best of their in calf cows reached £790 with others to £775, a pair at £770 and a second pair to £730.

On Friday the AHVLA Chief Scientist Glyn Hewinson gave an update to journalists about the progress being made into the research and development of vaccines against bovine TB for badgers and cattle.

Glyn spoke about the recent correspondence Defra and the AHVLA have had with the EU Commission about the timeline for licensing a vaccination for cattle that can then be used on a commercial basis. The EU Commission have set out a number of things that need to be done before a cattle vaccination can be used, including conducting field trials of the vaccine, and proving that the test we have to tell the difference between an infected cow and and one that has been vaccinated, is effective and reliable enough. the EU Commission have set a 10 yr timetable to complete the necessary work.

Glyn said:

"With cattle vaccines one of the most important new moves, I think, has been the engagement of Great Britain with the EU Commission to look at how we might start to try and introduce cattle vaccination as an option to TB control. "Very recently the EU Commission has mandated the European Food Standards Agency to come up with the requirements that they think they would require from a cattle field vaccine field trial in order to allow cattle vaccination in the UK, and the UK will be working very closely with both to take their recommendations and turn them into robust field trials that will help to inform Europe on whether cattle vaccination can be used as a control measure." On badger vaccinations, Glyn explained that an injectable vaccination is currently available and being used by groups in England and Wales, although the vaccine is not 100% effective, and it is both difficult and costly to use on a wide scale.

He said:

"You have to trap badgers, and its estimated that it costs between £2,000 to £4,000 per square kilometre.

"Oral delivery of vaccines would overcome this necessity to trap badgers, but it requires developing effective baits so that enough badgers take up the vaccine, and formulations that allow BCG to work when it's eaten."

Prof Hewinson said he was keen for more people to volunteer to get involved in helping out with the research, for which there is funding. "One of the big evidence gaps we have in TB control is how vaccinating badgers will affect TB in cattle," he said.

"One of the things we're very keen on is to encourage people to make use of Defra's funding pool for training lay vaccinators to go out and vaccinate badgers so that we can generate data to see what effect vaccinating badgers might have on cattle TB."

Asked about the oral badger vaccine, Glyn explained that more research was needed before a vaccine can be put forward for licensing.

He said:

The National Wildlife Management Centre, Animal Health and Veterinary Laboratories Agency (AHVLA), have submitted this blog post about the Farm Assessment Toolkit project, which is using surveillance cameras to help farmers improve biosecurity on thier farms and reduce the risk of infection spreading between badgers and cattle...

Recent research has shown that badger visits to farm buildings are widespread and common, but that some farms are more prone to badger visits than others.

As part of a two year study to better understand the reasons behind this, earlier this year AHVLA continued installation of infrared surveillance cameras at over 75 volunteer farms across the South West of England. Over a four week period the cameras count the number of badger visits to buildings, enabling the agency to develop a method to assess the risk of badger visits to any given farm, as well as to feed back to the individual farmers involved.

  “Ultimately, the study will help farmers consider whether to install biosecurity measures for their farms,” said Ian Vernon of the AHVLA Wildlife Team.

“We had a fantastic take-up from our volunteer farms and we’ve spent the last few months installing cameras - the final ones will be going up in August. We’re also starting to conduct individual surveys to understand badger activity near the farm buildings and to record details of farming practices and landscape features.

“There’s still a lot of work to do collating and analysing data to feed into our risk assessment methodology to refine the findings of last year’s surveillance, but we’ve made good progress and we’re starting to see images come back from the cameras installed this year. Some examples are included in this blog entry.”

  AHVLA is now writing to those farms to tell them how many nights badgers visited buildings, and to which areas, over the four week period. This will enable them to consider whether additional measures might help protect areas susceptible to wildlife visits, such as feed stores. For example, they might consider installing secure gates or electric fencing, and securing feed bags and bins.

On Friday a range of experts sat down for a webchat hosted by Farmers Weekly to discuss biosecurity and the measures farmers can take to help prevent the spread of bovine TB.

The five panelists were:

Andrew Cobner - a vet with 33 years of farm practice experience. He is a current member fo the British Cattle Veterinary Association with particular interest in infectious disease control.

Anthony Pope - Anthony is the lead advisor at the South West TB Advisory Group.

James Cossins - James is a fifth generation dairy farmer from Dorset. He milks 320 cows and has more than 300 other animals on farm.

Linda Evans - Linda is a veterinary officer working for the Animal Health and Veterinary Laboratories Agency (AHVLA). She is the UK representative on the EU Task Force Group for TB eradication.

Nick James - Nick is also from AHVLA. He helps lead the expert delivery network responsible for setting the standard for the implementation of Defra’s, and Scottish and Welsh Governments’ bovine TB policies.

The questions put to the panel and their answers can now be read on the Farmers Weekly website

Several news outlets over the weekend have run stories about meat from bovine TB reactor cows entering the food chain.

Each year thousands of cattle are compulsory slaughtered after testing positive for bovineTB during the programme of routine TB testing carried out by the AHVLA.

The owners of these animals that are slaughtered are then compensated by Defra and ownership of the meat passes to Defra. Every carcass then undergoes rigorous food safety checks by the Food Standards Agency (FSA). Only if a carcass passes these checks to satisfy the FSA that they show no signs of infection is the meat passed for human consumption. No meat that is infected is allowed to pass into the food chain.

The Food Standards Agency has confirmed that there are no known cases where TB has been transmitted through eating meat.

Charles Milne, a Director at the Food Standards Agency, said: ‘We are confident that the inspection systems in place are robust so that meat is safe to eat, otherwise we would not allow this meat into the food chain.’

Just this week, the European Food Safety Authority published a scientific opinion which stated that there is no evidence of meat-borne transmission of bovine TB in the EU.

These risks have been reviewed by the independent Advisory Committee on the Microbiological Safety of Food in 2002 and 2010, and by the European Food Safety Authority.

Several media reports also claim that the purpose of the badger culls this summer are primarily to protect human health. This is not the case.

The purpose of culling badgers is to reduce bovine TB in cattle, due to the disease’s huge impact on the farming industry, rural communities and taxpayers. Last year 28,000 cattle were slaughtered as a result of bovine TB, and fighting the disease cost the taxpayer £100 million. If the disease is not brought under control by tackling TB in cattle and wildlife, costs to the tax payer over the next ten years could top £1 billion. While humans can contract TB, it is currently quite rare and those who have close contact with infected animals or who drink unpasteurised milk are most at risk.

Professor Malcolm Bennett, Professor of Veterinary Pathology, University of Liverpool, said:

“The first thing to say is that this is not a new story and certainly not the discovery of any kind of cover-up or secret – the same story hits the headlines every few years, and the issue of whether or not there is any risk to public health has been looked at by expert groups not only in the UK but in Europe (EFSA). Cattle that test positive for TB are usually caught early during infection using a skin test that measures the immune response rather than a direct test for infection.  This is because it is very difficult to detect the bacteria until the animal becomes clinically ill, and because we want to diagnose and remove cattle from the population as early as possible and before they have the chance to infect other cattle. The farmer gets paid compensation by DEFRA, and DEFRA receives the price of the carcass at the abattoir in an attempt to offset some of the cost of compensation. The test-positive cattle are slaughtered at the end of the working day to minimise any risk of transmission or contamination, and like all carcasses, those of test-positive cattle are inspected for any signs of diseases that could stop the meat going off for human consumption: indeed these cattle are subject to extra scrutiny.  If there is no TB lesion, or only one site of TB lesions, then the affected organ is removed and the rest of the carcass goes off for human consumption – more than that (which would suggest spread of the disease) and the whole carcass is condemned.

“The bacteria don’t grow very well in muscle, so the risk of infection from traditional meat is lower still, and the bacteria are readily killed by cooking. The main risk is likely to be to people who handle infected/contaminated carcasses – and this is a well-recognised risk for American hunters handling venison, for example. Back when bovine TB was a huge public health problem (as it still is in some developing countries) the main source of human infection was drinking unpasteurised milk – the disease in humans of TB acquired by this route was called scrofula. The combination of controlling TB in cattle and, particularly, pasteurisation of milk has largely got rid of bovine TB in people in the UK: the few cases that are diagnosed each year are either imported cases or reactivations of infections from long ago or, occasionally, from drinking unpasteurised milk. 

By the Animal Health and Veterinary Laboratories Agency (AHVLA).

With the turnout of cattle for the grazing season all our TB testers have been very busy over the last couple of months.

We carry out tests for bovine TB for two main reasons; one is to routinely check all cattle herds to ensure that they are free from TB and can continue to trade. This routine TB testing is carried out once every four years in areas where TB is rare and every year in areas that have a lot of TB. The second reason is to remove all infected cattle from a herd that is found to be infected and to control the spread of infection to other herds. This testing is more frequent and can be carried out as often as every other month, until we are satisfied that all the infected animals in the herd have been identified.

The primary test for TB in cattle is known as the tuberculin skin test.  The aim of the test is to trigger and then measure an allergic reaction to bovine and avian tuberculins (‘cocktails’ of proteins and other antigens extracted from the bacteria that cause TB in cattle and birds respectively) when they are injected into the deep layers of the skin.

To carry out a skin test the tester has to first check the official ID (eartag numbers) of the all the cattle, then clip two small areas of skin in the middle of the animal’s neck, measure the thickness of both sites using callipers and inject all the cattle in the skin of the neck with a small volume of each tuberculin. The TB tester then returns three days later to examine the injection sites, look for any reactions to the injections and re-measure the skin thickness. These reactions will be in the form of lumps or swellings and the size and type of reaction (relative to the skin thickness measured before the injection of tuberculin) determine whether the animal is to pass the test, whether it is deemed a reactor (and slaughtered), or classified as ‘inconclusive’ (and re-tested 60 days later).

In order to obtain accurate results, TB testers have to adhere to the standard operating procedure meticulously. This  is not always easy under field conditions on cattle farms. Skin tests are also physically demanding on everyone as the cattle have to be gathered and restrained on two separate days. They can be quick and fairly easy where the cattle are used to being handled, such as dairy cows, but can take all day and leave the people involved with a number of bruises, crushed fingers or, in just a few cases, a hospital visit.

Here are a few tales from our testers:

Mark arrived at a farm at just before 10 am to carry out a test on 20 beef cattle:

“My heart sank when I walked into the yard. To carry out the test the animals need to be suitably restrained. Typically we use a crush, which is a strongly built stall for holding livestock safely while they are examined. But the crush on this farm was not suitable: the front gate didn’t close properly and the yoke didn’t work well. The cattle, including a 14 year old steer, were not used to being handled, were wary of the crush and jumped any gates used to herd them towards the crush. I was right to be anxious; the test took four hours, and one of those hours was taken up trying to restrain the 14 year old steer long enough to test it. The farmer was exhausted by this time and the cattle were even more worked up. As I left I suggested that we borrow the mobile crush belonging to a neighbour for the return visit in three days time, as the cattle would be even less likely to run through the crush on day two.”

Mariusz carried out his first TB test on a herd of 210 cattle, a mixture of Simmental crosses and Friesians:

By Gonzalo Sanchez-Cabezudo, Regional Veterinary Lead for the North of England, Animal Health and Veterinary Laboratories Agency

There has been some coverage this week about a small number of TB outbreaks in Lancashire and Cumbria, and understandable concern from farmers about how this could affect the region’s reputation as low risk areas for the disease.

Cumbria and Lancashire remain low risk areas for Bovine TB.

The five herds mentioned in the articles were confirmed in 2012. Each year we usually see a small number of bovine TB breakdowns in Cumbria and Lancashire, so these results do not suggest an increase in prevalence of the disease.

It is also worth considering that there are 3,500 cattle herds in Cumbria, and 2,100 in Lancashire, so five herds is a tiny fraction of all the cattle in the region.

The small number of herds with TB that we see in the region are typically due to infection being inadvertently carried in cattle bought from a herd in a high risk area.

The testing regime in these high risk areas – all cattle are tested every 12 months – is designed to reduce the risk of cattle carrying infection at the point of sale. There are also movement restrictions on cattle herds that have had a recent TB outbreak.

The three kilometre radial zone AHVLA have introduced around the infected herds in Cumbria and Lancashire is an example of one of the new measures brought in by Defra in January to tighten up the controls in place to limit cattle to cattle transmission. All cattle within this three kilometre zone, including those who graze in it, will have six monthly and 12 monthly tests. It is a new concept for most farmers but is an essential extra tool we can use to reduce the risk of infection.

Finally, to allay concerns raised in the article about the spread to wildlife, so far we have no evidence of bovine TB infection in wildlife in Cumbria or in Lancashire. To rule out spill-over infection to wildlife, a wildlife enhanced surveillance zone area has been in place south of Kirkby Lonsdale since January 2013. Deer being shot by stalkers in that area and badgers found dead have been tested in our lab and no lesions suspected of bovine TB have been found.