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Farming

‘False positives’ must be eliminated

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A NEW study performed by researchers from Cambridge University has recommended that new tests are needed to make vaccination against bovine tuberculosis (bovine TB). The report points out that in order for vaccination to be viable, the number of false positives from these tests must be significantly reduced. The scientists have said the reduction in false positives in cattle is feasible, but that a vaccination programme would be challenging. Despite an intensive, and costly, control program in the United Kingdom, bovine TB persists. Although vaccinating cattle with the human BCG vaccine offers some protection in cattle, doing so is currently illegal within the EU, due to the vaccine’s interference with the skin test used for surveillance.

The Cambridge team worked alongside researchers at the government’s Animal & Plant Health Agency (APHA), to show the importance of specificity – the proportion of uninfected animals that test negative – to making disease control strategies work. The skin test currently in use has a very high estimated specificity of over 99.97%, which means that less than three animals in 10,000 will test falsely positive. However, the test as carried out in Great Britain is thought to have at best an 80% sensitivity – a measure of how many infected animals will correctly test positive – missing around 1 in 5 bovine TB-infected cattle.

It is used to determine if animals, herds and countries are officially free of bovine TB. Vaccinated animals that test positive have to be treated as infected animals. Under European law, if an animal tests positive, it must be slaughtered. The remaining herd is put under movement restrictions and tested repeatedly using both the skin test and post-mortem examinations until it can be shown to be officially clear of infection. Researchers said the duration of movement restrictions is important due to the considerable economic burden they place on farms. Also, the cost to the UK government alone is estimated to amount to half a billion pounds over the last decade; this cost includes visits to farms by veterinarians, tests carried out and compensation for the slaughter of infected animals. For vaccination to be economically viable and acceptable within the EU, the benefits of vaccination must be great enough to outweigh any increase in testing.

A new generation of diagnostic tests, known as ‘Differentiate Vaccinated from Infected Animals’ (DIVA) tests, has opened up the opportunity for the use of BCG within current control programmes. The EU has recently outlined the requirements for changes in legislation to allow cattle vaccination and a recent report from its European Food Safety Authority (EFSA) emphasized the importance of demonstrating that BCG vaccine works, and that DIVA tests can be shown to perform in large-scale field trials. However, a key factor overlooked in the EU report was that the currently viable DIVA tests have a lower specificity than tuberculin testing; this could lead to vaccinated herds being unable to escape restrictions once a single test-positive animal has been detected, as the more times the herd is tested, the more likely the test is to record a false positive.

In their study, the researchers from Cambridge and APHA used herd level models to show that the level of infection can be reduced in vaccinated herds even when DIVA sensitivity is lower than tuberculin skin testing. However, in order to see this benefit of vaccination over 99.85% of uninfected animals will need to test negative in the DIVA test. This improved accuracy will be necessary to avoid increasing the duration of breakdowns and the number of animals condemned. Using data from previous tests on cattle, the researchers said this level of ‘specificity’ is achievable, though they said there will be challenges associated with improving accuracy. The researchers said, “Currently, there is no gold standard test to diagnose TB in cattle.

Cattle that test positive are slaughtered immediately and therefore have rarely developed any physical signs – in fact, only around a half of animals examined post-mortem show physical signs of infection even if they are, indeed, infected.” Dr Andrew Conlan from the Department of Veterinary Medicine at the University of Cambridge explained “In order for vaccination to be viable, we will need a DIVA test that has extremely high specificity. If the specificity is not good enough, the test will find false positives, leading to restrictions being put in place and a significant financial burden for the farmer. “But validating a test that has a very high specificity will in itself be an enormous challenge. We would potentially need to vaccinate, test and kill a large number of animals in order to be confident the test is accurate. This would be very expensive.”

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Community

Work underway to tackle ash dieback disease

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WORK is underway in Carmarthenshire to tackle a serious fungal disease which is affecting ash trees across the country.

It is estimated that 90% of ash trees could die from ash dieback disease for which there is currently no known treatment.

The fungus infects the leaves and spreads through to the branches, causing the tree to eventually die. Dead branches and the trunk of the tree can become very brittle causing it to fall, posing a serious risk to both people and property.

The council is taking a risk-based approach to tackling the issue and ash trees along all Class 1 and 2 roads, the county’s busiest roads which make up 17% of the total highway network, have been surveyed.

Trees showing at least 50% of ash dieback in their crowns and which pose a risk to road users will have to be felled. A total of 2,512 trees have been identified.

Felling work will start later this month in Llanelli along the A4138 between Trostre and Llangennech where 215 trees along the stretch will be felled. This is the busiest road in the county for which the council is responsible.

The works are scheduled to start at Penprys roundabout on Wednesday, February 26 and are expected to take eight days to complete with the final phase taking place at the Talyclun junction on Sunday, March 1. The majority of works will be carried out from the cycle path to maintain traffic flow as much as possible and between 9am and 3pm to avoid rush hours.

The council will be writing to private landowners with trees alongside Class 1 and 2 roads offering guidance and advice on how to deal with ash dieback.

Surveys are also being carried out on ash trees on other council-owned land such as schools, car parks, council housing areas, safe routes and cycle paths. Surveys on ash trees alongside Class 3 and 4 roads will follow.

Executive Board Member for the Environment Cllr Hazel Evans said: “This is a very sad situation, but unfortunately we have no choice but to remove the trees if they have the disease and are in a location which poses a risk to public safety. We will try to minimise the disruption to road users as much as possible.

“It is a serious problem for both councils and other landowners across the UK and a lot of work is being carried out. It is important we raise awareness of the disease, particularly with landowners to offer guidance and advice, as well as the public in general.

“There will be a need for new trees to be planted to compensate for the loss of ash trees in the county, and we will be actively seeking funding to support re-planting projects.”

Symptoms of ash dieback disease are usually first apparent in the crown of the tree, with leaves turning black and falling in late summer rather than autumn, there can also be visible lesions above and below the point where the branches join the trunk of the tree.

For further information including frequently asked questions and advice please visit the website carmarthenshire.gov.wales/ashdieback

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Farming

Young hill farmer stars in £250,000 campaign

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AN ACCOMPLISHED young farmer from the Ceiriog valley is starring in a nation-wide campaign promoting PGI Welsh Lamb and Welsh Beef.
Caryl Hughes, who farms in partnership with her family near Llanarmon Dyffryn Ceiriog, features in Hybu Cig Cymru – Meat Promotion Wales (HCC)’s latest campaign.
The £250,000 campaign was announced in November 2019 by HCC Chair Kevin Roberts at the annual HCC Conference and will focus on Welsh red meat’s sustainable qualities. The campaign will include radio and tv advertising, on-demand tv advertising, print advertising and media partnerships. It will also feature core messages around Wales’ sustainable red meat production focusing on elements such as – landscape, climate and water usage.
The television advert sees Caryl at home on her farm in Ceiriog valley and displays the dramatic landscapes and natural surroundings where Caryl rears her own flock.
Caryl is a familiar face within Welsh agriculture; having previously held the role of National Sheep Association Young Ambassador and Montgomery YFC Chair.
Caryl has a degree in Agriculture from Aberystwyth University and, notably, was the first person to undertake the Llyndy Isaf Scholarship with the National Trust – where she managed a Snowdonia hill farm for a year combining sustainable farming practices with managing the outstanding natural environment.
Having also competed on S4C’s Fferm Factor, Caryl is also someone comfortable both on film and in the field.
Commenting on the campaign, Caryl said ‘Like most Welsh sheep and beef farmers, I am very proud of our industry, the food we produce and how we produce it. I’m very pleased to be involved in this campaign promoting exactly that.’
HCC’s Market Development Manager Rhys Llywelyn commented ‘We wanted the real, authentic voices of Welsh farming to star in this campaign to show the real picture of Welsh red meat production.’
‘Caryl’s knowledge, passion and experience are undeniable and she is a very credible ambassador for our industry and produce. We’re sure viewers and consumers at home will find Caryl very relatable and engaging in this advert’
HCC’s new campaign launched on Thursday, February 13, and can be seen and heard on on-demand television platforms and radio stations throughout England and Wales.

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Farming

New DEFRA Secretary appointed

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BORIS JOHNSON’s controversial Cabinet reshuffle, which appeared to reward loyalty over competence in several instances, resulted in the appointment of a new Secretary of State at DEFRA.
George Eustice, previously a Minister of State at the department before resigning in February 2019, joined the Cabinet.
He replaced Theresa Villiers in the role.
Mr Eustice comes from a farming background. His family runs a fruit farm, restaurant and shop in Cornwall, where they have a herd of South Devon cattle and British Lop pigs.
Mr Eustice made the headlines in 2016 through being of two Conservative DEFRA ministers who were accused by environmental campaigners of having a conflict of interest over receiving subsidies on their family businesses while being involved in developing the plans for the replacement system to the EU farming support.
The replacement of CAP and tackling the pressures tariffs planned by the Government will affect the UK’s farming industry will be high on Mr Eustice’s ministerial in-tray.
If the UK Government makes good on its promise to significantly diverge from the existing tariff-free arrangements with EU, something which both Westminster and Brussels accept is increasingly likely, farmers are in for a bumpy ride.
Although the UK Government says it wants trade to be ‘as frictionless as possible’, it now accepts that there will be winners and losers. While large English arable farms are likely to be (comparatively) little worse off, Welsh livestock farmers stand as those most likely to be hit hard by tariff changes and any lowering of animal welfare, hygiene, and health standards when the UK strikes trade deals with large markets overseas. America, Canada, Australia, New Zealand, Brazil, and Argentina will want market access on their terms as part of any cross-sector trade agreement. The interim tariffs the Government plans to introduce will, all Wales’ farming unions agree, slash Welsh red meat exports to their biggest market.
After his resignation from Theresa May’s government, Mr Eustice, a vociferous Brexiteer, wrote an article for the Guardian in which he set out his concerns about the UK’s trading relationship with other countries after Brexit.
Mr Eustice wrote: ” I believe in open markets and want us to have an independent trade policy. There is a negotiation to be had about allowing tariff-free quotas on some products as part of a future UK-US trade deal. However, if Americans want to be granted privileged access to the UK market, they will have to learn to abide by British law and British standards or kiss goodbye to any trade deal and join the back of the queue.”
Mr Eustice is now, at least superficially. in a much stronger position to put his words into action.
As the responsibility for sorting out a new support mechanism was handed over by the Welsh Government to the Westminster, the short to medium term future of Welsh farming rests in George Eustice’s hands. Meanwhile, the Cardiff Bay government’s plans, which contained more pie in the sky than an explosion at Peter’s Pies’ factory, are stalled while it waits to see how much it can carve out of farm subsidies to fund its dream of reducing the amount of Wales’ sustainable farmland.
Responding to George Eustice’s appointment, CLA President Mark Bridgeman drew attention to the new Secretary of State’s record at DEFRA.
“We warmly welcome Mr George Eustice to his role at this pivotal time for British agriculture,” Mr Bridgeman said.
“As a long-standing Farming Minister, he will know the scale of the challenge ahead. We will work closely with him to help achieve the full potential of the rural economy.”
NSA Chief Executive Phil Stocker also drew attention to Mr Eustice’s ministerial experience, saying “We hope to continue our strong working relationship with him as agricultural policy evolves in the future as we enter into new farming support schemes and trade arrangements.”
TFA Chief Executive, George Dunn was enthusiastic about the appointment
Mr Dunn said: “It’s great to have a Secretary of State at DEFRA who really wanted the role. George Eustice has the depth of experience, enthusiasm, passion and ideas to really make a difference in this role at such a crucial time for the farming industry as we move into a brand-new policy era.
“George has been particularly mindful of the needs of the tenanted sector of agriculture and we look forward to working with him in his promoted role.”
While NFU-Cymru President John Davies congratulated Mr Eustice about his promotion, he also sounded a note of caution.
Mr Davies said: “The new Secretary of State will have a vital role to play in ensuring the industry can capitalise on the new opportunities afforded to us now the UK has left the European Union. As we embark on this new era, we urge the new Secretary of State to work with his colleagues in the new UK Government Cabinet to ensure that the standards which form the solid foundation of the UK food and farming industry are not compromised in forthcoming negotiations over future trade deals. Mr Eustice’s predecessors have vowed to protect and uphold these standards and we would welcome his commitment to reinforce this pledge at the earliest opportunity.”
John Davies continued: “NFU Cymru is keen to meet with Mr Eustice in the coming weeks to outline our vision for a productive, progressive and profitable food and farming industry in Wales and the role that the UK Government can play in helping us to realise our vision.
“The union’s officeholder team and staff have met with Mr Eustice on several occasions in his previous capacity as Minister for Agriculture, Fisheries and Food. We look forward to continuing that good working relationship.”

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