Instructions have been issued to OVs in respect of the permanent marking of bovine TB reactors using DNA tags. These instructions will need to be followed by all OVs who undertake tuberculosis testing of bovine animals on premises in England and Wales.

In March 2011, Defra announced that cattle testing positive for bovine TB would be DNA tagged in order to further strengthen controls preventing spread of the disease. The decision to tag cattle came about after evidence revealed that some cattle farmers in the South West of England and the Midlands may have been illegally swapping cattle ear tags.

It is thought these farmers may have been retaining highly productive but TB positive animals in their herds and sending less productive animals to slaughter in their place. The alleged evidence of fraud emerged from an investigation instigated by Gloucestershire Trading Standards, which reviewed TB reactors sent to two slaughterhouses.

The application of tags to reactors is being implemented to help identify infected animals and ensure their valuation, removal and slaughter. It also discourages fraud and helps identify cases where fraud has taken place. Retaining cattle in herds when they have tested positive for TB obviously increases the risk of TB being spread to other herds and wildlife. Official Veterinarians are being urged to reinforce this point with their clients.

Instructions are available on the Animal Health website. They should be used in conjunction with existing instructions for undertaking TB skin testing. AHVLA are in discussion with the British Veterinary Association (BVA) with a view to agreeing how OVs will be reimbursed for this work in future and we hope to be able to implement the proposals during the next few months.

The Scottish Government has decided not to use the DNA tagging system being rolled out across England and Wales. Instead, they have opted for insertion of a reactor tag in the ear of the affected animal.