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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

Economic value of red meat sector rises

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THE VALUE of the iconic beef, lamb and pork sectors to the Welsh economy rose in 2020, as consumers turned to local, sustainable, quality food during the COVID pandemic, according to analysis by Hybu Cig Cymru – Meat Promotion Wales (HCC).New figures from the Welsh Government ‘Aggregate Agricultural Output and Income’ report show that the total value of agricultural output in Wales for 2020 is projected to stand at £1.7billion – a 6.2% (or £99 million) increase on the provisional figure for 2019.


Cattle and sheep account for 44% of this total at £750million; the highest proportion recorded since 2016. The agricultural output value for Wales’s pig sector also increased (by 34.3% or £2 million) to a value of £8 million.
The figures reflect the strength of the livestock sector in Wales and sit in contrast to Total Income From Farming (TIFF) figures for the UK as a whole newly released by Defra. Although the TIFF figures are a different form of measuring farm production, the UK data concurs that the livestock sector has had a strong year, but in other parts of Britain, this was more than offset by poor harvests in the arable sector.


Demand for beef and lamb have been strong in the domestic retail market since the immediate aftermath of the first COVID lockdown in spring 2020. After initial market volatility, marketing campaigns by HCC and other bodies encouraged consumers to recreate restaurant meals at home.


Over the past 12 months, domestic retail sales of lamb and beef have trended consistently higher, with spending on lamb 20% higher than the previous year. Sales at independent high street butchers are also strong.


Research shows many demographic groups, including families with children, buying more beef and lamb than previously, and turning to quality home-grown produce.


HCC Data Analyst Glesni Phillips said, “The strong demand for red meat from the domestic consumer has helped drive market prices for beef and lamb at Welsh livestock markets in the second half of 2020 and into the early months of 2021.

“It’s no surprise, therefore, to see that the overall value of the industry is projected to have grown. We have seen inflation in the costs on farmers, which offset some of the gains from improved market price; however, it’s heartening to see consumers’ support for quality Welsh produce.“Welsh Lamb and Welsh Beef remain key drivers of our rural economy, and given their excellent brand reputation, they act as flagship products for the growing Welsh food and drink sector.”Further analysis of the aggregate output and income figures for Welsh farms are available in HCC’s latest monthly market bulletin.

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Farming

Ian Rickman: 2021 is a critical year for Wales’ farming future

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THE INCREASINGLY negative narrative around livestock farming and its portrayed impact on the environment and climate change has led to farmers in Wales standing up to tell their stories and highlight the positive impact livestock farming has.


Through the Farmers’ Union of Wales’ campaign ‘Guardians of the Welsh Land’, farmers are addressing misleading claims by various groups about the role livestock farming plays in relation to climate change and the environment.  Launching the campaign, FUW Deputy President Ian Rickman said: “The FUW has consistently recognised the threat represented by climate change and the need to take action. This is clear from a cursory look at our manifestos and policy documents published over the past twenty years.


“We know that farming is already responsible for a critical carbon resource in soils, woodland and semi-natural habitats and I’m pleased to launch the FUW’s environment campaign – ‘Guardians of the Welsh Land’ from my home farm here in Carmarthenshire today. As farmers are the most trusted link in the supply chain, they are best placed to communicate their stories, helping to address consumer concerns and influencing political agendas. Members can also look forward to a variety of webinars over the coming months, which will focus on the different challenges ahead for the industry and how to overcome them.


“There is no question in our mind that we need to counteract the continuation by the anti-farming lobby of their campaign to vilify and belittle domestic food producers.  These attacks are corrosive and grossly misleading, negatively influencing consumer perception of the industry and influencing political agendas on a global scale.”
Mr Rickman added that 2021 is an important year for these types of conversations.
“Knocking on our door are the United Nations Food Systems Summit and COP26. The FUW has been engaging with these conversations at an international level and shares some concerns with other industries across the globe about the wider narrative and ambitions set out in inconspicuous looking documents. Plans, we and the general public don’t support.  Telling the positive story of the guardians of our Welsh land is now more important than ever,” he said.
Starting in the first week of June, the campaign introduces four farmers all of whom tell the story of how they are addressing environmental and climate change needs in their unique ways: Carmarthenshire organic sheep farmer Phil Jones, the Roberts family from Meirionnydd, Ceredigion dairy farmers Lyn and Lowri Thomas and FUW President Glyn Roberts who farms with his daughter Beca at Dylasau Uchaf in Snowdonia.

“The campaign will further highlight that Welsh farmers are rising to the challenge of improving soil health and increasing organic matter in soils, improvements which represent further opportunities for sequestering more carbon. These improvements, the campaign will highlight, are achieved through specific livestock grazing patterns and rest periods. The campaign is also clear that the correct options, guidance and rewards are required to encourage more farmers to adopt such systems,” said Mr Rickman.


Soil, the campaign will stress, is a long term investment and at present, around 410 million tonnes of carbon is stored in Welsh soils and 75,700 hectares of Wales’ woodland (25%) is on farmland, representing an important and growing carbon sink.

“As acknowledged in Natural Resources Wales’ State of Natural Resources Report, using land for food production is an essential part of natural resource use and management.  Whilst we acknowledge that  agricultural intensification has undeniably had negative impacts on some species and ecosystems, there is overwhelming evidence that other factors, including reductions in agricultural activity and afforestation, have also had severe negative impacts,” he added.

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Farming

Excellent Easter for lamb sales

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Lamb proved a popular choice for consumers over Easter with retail sales soaring above the last two years. This demand has been reflected at livestock markets where farmgate prices are still standing strong.

At a time when lamb is always a firm favourite, this year people of all ages were both buying and spending more as a result of a renewed interest in sourcing quality, local produce and cooking at home.

In the 12 weeks to 18 April 2021, the total volume purchased was up 14.8% on the year, and 6.0% higher than in 2019. Consumer spend on lamb reached £190.0 million, which was 18.7% more than in 2020 and 14.6% higher than the same period in 2019.  

Lamb leg roasting joints were the most sought-after cuts despite the fact that Covid-19 restrictions on large gatherings remained, followed by chops and mince.

Hybu Cig Cymru – Meat Promotion Wales’ (HCC) Data Analyst, Glesni Phillips said: “Lamb performed exceptionally well over the Easter period this year. It saw a 10.2% increase in the number of buyers engaging with the product and a rise of 3.3% in the frequency of which lamb was bought.

“The average price of lamb was also higher, but this obviously did not deter new buyers. The figures show that there are new buyers in all age categories, but this is especially true for shoppers aged under 45 years and those with children.

“The pandemic has led to more consumers cooking at home, giving many the opportunity to realise and enjoy the exceptional qualities and versatility of Welsh Lamb, and at the same time, support the local economy.”

Butchers also benefitted from the popularity of lamb in the run-up to Easter with total spend increasing by 16.1% on the year. The volume sold also increased, by 12.6%.

Glesni Phillips added: “As we approach the end of Spring, the consumer demand for lamb is continuing. This can be seen in the liveweight lamb prices which remain strong when compared to historical averages, with the average SQQ in Wales standing at 329.7p/kg in Wales for the week ending 15 May 2021.

“New season lambs are now entering the market – they accounted for over 70% of lambs at auction in Wales during the latest week – but the supply is still relatively tight. HCC is looking forward to working with retailers over the coming months on new activity, which will include in-store marketing, press and targeted digital communication to maintain this growth in sales. Butchers, who demonstrated their key role in the community during the pandemic, will also be offered training on a number of key skills to boost their sales even further.”

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