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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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Farming

Investment in Welsh Lamb vital

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WELSH LAMB has a “fantastic name” all over the world but it was vital it received continued investment post-Brexit to differentiate it from keen competitors in the global marketplace, former Waitrose chief Lord Mark Price told farming industry leaders at Hybu Cig Cymru-Meat Promotion Wales’ (HCC) annual conference.
“Everything that we have become used to is about to change,” he said. “I would suggest there is no time to waste in developing a new, globally-minded approach and prepare to become match fit to win in a new global game.
“Your competitor is no longer the farm next door or even the neighbouring county- it will be Mexico, Argentina, New Zealand or Australia. In the future, the UK doesn’t have to just compete against the other 27 EU countries but instead will have truly global competition- and opportunity.”
Lord Price, a former Minister of State for Trade and Investment, and then Trade Policy, said differentiation was vital for Welsh Lamb, “Why is your product better than one from Ireland or New Zealand? Welsh Lamb has a fantastic name all over the world- but you still have to invest in that.”
He felt in the future the UK Food Service industry offered a fantastic opportunity for market growth for Welsh Lamb and Welsh Beef. “It’s around 35 per cent of the market here but in the US it’s 50 per cent and there’s only one way of travel so it’s a going to be a great opportunity.”
Lord Price was Managing Director of Waitrose from 2007-16. In his view, there were three potential European Union trade deal options for the UK post Brexit: No deal, a form of customs union and a free trade agreement. “I believe the third is the most likely long-term outcome. The UK strikes a comprehensive free trade agreement with the EU and, in doing so, is free to strike other advantageous trade deals.
“Such a deal would be based on zero tariffs and regulatory alignment in areas where it made sense to do so- say pharmaceuticals or automotive, where frictionless trade is key- and in Food and Drink, given the importance of our relationship with Ireland.
“If there are tariff and regulatory alignment with technology to track goods, this could provide the components for having, as near as possible, frictionless trade- all of which suggests the UK can strike mutually beneficial trade deals internationally, reducing the cost of goods to British consumers,” he reasoned.
Regarding public concerns over the possibility of new trade deals enabling food imports such as chlorinated chicken, Lord Price said he felt the Department of Trade would ensure it operated strictly in line with established food policies as positioned by Defra on a wide range of matters including standards, labelling, welfare and packaging.
He said environmental concerns were moving up the political and consumer agenda. “I’ll leave for now the issue of how subsidies might swing to reward sustainable behaviour- but I would just like to remind you that it was more than a decade ago that Walker’s started to label carbon content on crisp packets.
“The scheme did not take off but I suspect supermarkets responding to consumers will move again towards measuring carbon impacts of their products and the Government will see this as an “oven-ready” popular tax.
“Red meat, I suspect, will face a challenge- which, from what I have heard from HCC and others today, you will be well prepared for,” said Lord Price.
In encouraging news for Welsh Lamb farmers, NFU Cymru has welcomed Waitrose & Partners plans to source all of its own-label fresh and frozen lamb from Welsh and British lamb producers 365 days a year from June 2021.
NFU Cymru Livestock Board Chairman Wyn Evans said: “We thoroughly welcome Waitrose’s commitment to stock 100% Welsh and British lamb from 2021. This comes at a time of great uncertainty for the sheep sector, so today’s news that Waitrose will be moving to a year-round supply of Farm Assured quality Welsh and British lamb is a welcome boost.
“This is a really positive move from one of the major buyers of lamb in the UK which highlights that there is a strong appetite amongst consumers for Welsh and British lamb products. We look forward to working in partnership with Waitrose to help further grow sales of great-tasting Welsh lamb.”

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Frictionless trade vital for meat industry

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GIVING evidence to a powerful committee of AMs this week, Hybu Cig Cymru – Meat Promotion Wales (HCC) Chief Executive Gwyn Howells acknowledged that preparing for four different Brexit deadlines has been tiresome for the industry over the past year.
He emphasised, however, that free and frictionless trade with Europe was still crucial for the lamb and beef industries.
Addressing a meeting of the External Affairs Committee in the Senedd, Gwyn Howells discussed the extensive contingency planning that HCC and others, in co-ordination with Welsh Government, had undertaken since 2016.
“Welsh meat exporters have been consistent in raising alarm at the prospect of massive WTO-level tariffs if the UK leaves the EU without a deal,” said Gwyn. “However non-tariff barriers such as additional paperwork and delays at ports are also a concern. In the event of a Brexit deal, a lengthy transition period may be needed to get these issues right. It was good to have the opportunity to discuss this matter with AMs.”
He added, “Companies, as well as customs authorities, will have to be aware of what’s needed in terms of non-tariff barriers, but with exporters having had to prepare for several political deadlines already, ‘Brexit Fatigue’ is an issue.”
Gwyn Howells referred to collaborative work, such as the Welsh Government-funded Enhanced Export Programme, which was showing dividends in growing new markets. But he warned that this could not replace free access to established European customers.
“Over the past year, we’ve seen trade begin with a number of new countries such as Japan, and there are promising signs that Welsh Lamb exports to the Middle East will be substantially up in 2019, partly thanks to HCC’s ongoing work in the region reinforced by Welsh Government help,” he said.
“However, the lamb trade to Europe is worth over £120 million a year, so continued free trade with our nearest neighbours is vital whatever political solution is found.”

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Farming

Payment commitment sought from minister

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NFU CYMRU has asked the Minister for Environment, Energy and Rural Affairs to make an early commitment to maintaining the Basic Payment Scheme in Wales for 2021.
In a meeting this week NFU Cymru President John Davies asked the Minister, Lesley Griffiths AM, to commit to maintaining the Basic Payment Scheme unchanged for 2021.
Speaking after the meeting, John Davies said: “The events in Westminster these last few days mean that our future relationship with the EU remains as uncertain as it has ever been, with the prospect of a general election in the not too distant future, this means further political upheaval, and by extension more uncertainty. The fact that the UK Government’s Agriculture Bill was not carried forward when parliament was prorogued means that the intended legal basis for setting Welsh agricultural policy has now also disappeared, and we are now essentially back to square one.
“At the end of last year, Welsh Government announced that the Basic Payment Scheme would remain unchanged in 2020; we welcomed that announcement as it offered Welsh farming some stability at a critical time. The uncertainty in the intervening period has only intensified, NFU Cymru considers the possibility of a disorderly Brexit to be a very live possibility, either after a failure to reach an agreement at the end of any extended Article 50 period, or alternatively if the UK fails to agree on a future trading relationship with the EU27 during the transition period.
“There are many factors completely outside of our control which considered individually or collectively would have a very detrimental impact on Welsh agriculture. NFU Cymru is very much of the view that this calls for a cautious and restrained approach from the Welsh Government when it comes to developing future agricultural policy. We would urge Welsh Government to take its time and not to hasten to move away from the present arrangements until we have a far clearer picture of the sort of future trading relationship we will have with the EU27.
“We fully respect that the timing and nature of Brexit, the general election and the fate of the Agriculture Bill are all outside the hands of Welsh Government, but what we do ask for is the support of Welsh Government on the areas that sit within its remit. In our meeting with the Minister, we have asked if she will make an early commitment to the continuation of the BPS unchanged for 2021.
“We have also asked the Minister to ensure that the additional £5.2 million per year for the next two years made as part of the UK Government’s response to the Lord Bew review last month is used as a top-up to the BPS. This funding has been allocated to Wales because average Pillar 1 payments have historically been lower in Wales than in some other parts of the UK. We therefore firmly believe that as the Lord Bew review was about correcting this matter then the additional money should be made as a top-up to the BPS and not spent elsewhere.”

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