Bovine viral diarrhoea
Bovine viral diarrhoea (BVD) occurs worldwide and can affect cattle of all ages
This guidance is for Wales
Bovine viral diarrhoea (BVD) can have very varied symptoms and may result in death. It can have substantial impact on the profitability of farms. This highly contagious disease costs UK farmers an estimated £61 million per year. It impacts animal welfare within affected herds and reduces farm productivity and profitability.
Following pressure from the agricultural industry, the Government introduced a funded voluntary programme between 2017-2022 to attempt to tackle the disease in Wales.
CLINICAL SIGNS
Clinical signs can vary greatly, such as a bout of diarrhoea or pneumonia (often in a group of animals), or an increase in abortions / stillbirths and a decrease in fertility and lower conception rates. BVD can also cause return to heat, embryo deaths, deformities and weak or premature calves.
Calves contracting the disease while still in the womb can be born as 'persistently infected' animals (PIs*). Such animals continue to excrete the virus throughout their lives and are therefore the greatest risk of spread of infection. These animals, as well as failing to thrive, tend to have impaired immunity, making them more susceptible to other diseases. They are likely to die before reaching maturity. Cattle infected after birth can recover from BVD.
[*For ease of reference, all animals that are BVD positive are referred to in this guide as PIs.]
BVD is spread via contact with infected cattle, particularly PIs. A thorough BVD testing regime, movement restrictions and good biosecurity controls are required to eradicate this disease.
BVD TESTING
In September 2017, the Government announced funding for a voluntary BVD screening programme in Wales called Gwaredu BVD (the funding has now ended). In England and Wales, the BVD eradication programmes remain voluntary and are not supported by legislation. BVD schemes in Scotland, Northern Ireland and the Republic of Ireland have statutory requirements and are backed by legislation, as BVD is one of the biggest disease issues affecting the cattle industry.
In Wales, Gwaredu BVD is the national, voluntary, industry-led scheme; it has the aim of eradicating BVD. The scheme had a steering group made up of Coleg Sir Gar, Royal Veterinary College (RVA), National Farmers Union (NFU), Farmers Union of Wales (FUW), Iechyd Da, Milfeddygion, Gogledd Cymru, Scotland's Rural College (SRUC), Farming Connect, British Veterinary Association (BVA), Hybu Cig Cymru (HCC) and the levy-funded Agriculture and Horticulture Development Board (AHDB). The Minister for Agriculture announced in January 2023, after public consultation, that they will be bringing legislation forward in the next financial year for the eradication of BVD in Wales.
Whilst there is currently no legislation specifically for the control of BVD in Wales, there are supporting assurance schemes such as Red Tractor Dairy, which requires farmers to have a BVD elimination plan in place or a CHECS accredited scheme. The Code of Practice for the Welfare of Livestock: Cattle (see paragraph 27) indicates that the written health and welfare plan should as a minimum cover specified diseases, of which BVD is one.
All herds enrolled under a CHECS scheme must declare the results of any screening carried out during the previous 12 months to either their own veterinary surgeon or a health scheme provider.
Any blood samples must be taken and submitted by a veterinary surgeon.
The route to establishing herd BVD-free status in a dairy herd is slightly different to that of a beef herd.
HERD STATUS AND MOVEMENT RESTRICTIONS
Ultimately, BVD elimination will only happen with support and a coordinated approach from farmers, veterinary surgeons and the agriculture industry.
Under CHECS there are three standard programmes for BVD:
- Accredited Free (AF) Programme - demonstrating the herd is free from BVD
- Vaccinated Monitored Free (VMF) Programme - demonstrating that BVD is controlled through vaccination of the breeding herd and by regular monitoring of young stock
- Eradication Programme - implements a control programme to reduce the detrimental effects on herd productivity caused by the disease and to achieve freedom from the disease
To maintain the status, under CHECS, check tests are carried out on successive calf crops. Where animals have been confirmed as PI they must not be sold on, except to slaughter. CHECS also requires movements off the farm to meet specified conditions, such as being kept separate from non-accredited cattle. The full requirements are detailed in the CHECS technical document.
MINIMISING RISK
PI animals are highly infectious and should be culled as soon as they are identified. PI animals should not be traded. Other cattle in the herd may be transiently infected, although they can be traded if not identified as a PI.
Spreading the BVD virus through movement of the animal puts other herds at risk and undermines the national effort to eliminate the BVD virus from Wales.
Means of reducing risk include:
- practice good biosecurity
- avoid buying in pregnant animals, as calves that contract BVD in the womb can become PIs for BVD. Also avoid taking pregnant animals to shows
- avoid nose-to-nose contact with cattle from neighbouring holdings
- vaccination may be an option but this should be discussed with your vet
CAN PEOPLE CATCH THE DISEASE?
BVD is not known to affect humans but good hygiene procedures should always be followed after contact with livestock.
COULD IT AFFECT THE FOOD I EAT?
No, it does not affect food we eat and it cannot be contracted by consuming beef or dairy products.
FURTHER INFORMATION
More detailed guidance is available from CHECS.
TRADING STANDARDS
For more information on the work of Trading Standards services - and the possible consequences of not abiding by the law - please see 'Trading Standards: powers, enforcement and penalties'.
IN THIS UPDATE
New guidance: April 2024
Key legislation
Please note
This information is intended for guidance; only the courts can give an authoritative interpretation of the law.
The guide's 'Key legislation' links may only show the original version of the legislation, although some amending legislation is linked to separately where it is directly related to the content of a guide. Information on changes to legislation can be found on each link's 'More Resources' tab.
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