The role of badgers in the spread of bovine tuberculosis in pigs

Reducing the risk of bTB infection from badgers

Knowing where badgers are will enable you to put suitable and approved biosecurity measures in place to reduce the risk of them entering your farm.

When levels of bTB circulating among wildlife and cattle in the local environment become very high, it spills over into other species, which are not usually infected with bTB.

This situation is most likely to occur in bTB hotspots, such as the South West and the Midlands. However, it is essential that all producers are vigilant due to ‘off-site’ contract growing and finishing, and pigs being moved between regions for finishing.

Badgers are a protected species, which means it is essential to prevent any undue harm to them. If you're not sure what to look for, these factsheets provide useful advice and signs to look out for.

Diet and habitat of badgers

• Badgers are members of the weasel family and are omnivores. They eat worms and slugs as well as small invertebrates, hedgehogs, rabbits and other small mammals. They will also eat carrion, birds’ eggs, berries and fruits, maize, oats, barley, and anything else that is available when food is scarce
• Badgers can live five to eight years and mate at almost any time of the year. They will use the same setts for several years, with many large setts having been in existence for hundreds of years
• Badgers have a sense of smell over 800-times more sensitive than our own. They will use well-worn runs emanating from the sett and mark their territory boundary using established latrines and dung pits

Detecting infection in badgers

There is no evidence to suggest that sick animals are ejected from the main sett or family group, but there is some evidence that infected badgers have a larger home range. This may lead them to occupy single-hole setts away from the main sett, often located close to an easy food source.

• It is not possible to tell if a badger is infected with TB by sight
• If setts are being used close to your outdoor paddocks, buildings and feed stores, be mindful of this. Badgers will also live under sheds, in straw stacks and in barns – check these areas regularly for obvious signs of badger access
• Many cattle farms locate water, feed troughs and salt licks over 4 feet (120 cm) off the ground to prevent badgers accessing them. As this is impossible for pig producers, it is essential to implement good biosecurity

Practical biosecurity

• Access to feed and stored grain should be prevented wherever possible. Badgers can easily climb 3 feet (91 cm), especially if the surfaces provide grip, such as concrete. Any permanent field fences should have wire buried 0.5 m underground to prevent digging beneath
• If doors and gateways are more than 3 inches (8 cm) off the ground, a badger can get under them. If the floor is soft, a badger can scrape under a gate, so modification with plastic strips, corrugated steel sheets or electric fencing is required. Ensure all grain stores have doors that shut flush together
• Entrances that are unsecured with gates should be fitted with a solid gate no more than 3 inches (8 cm) from the ground
• Keep up good housekeeping around the feed-bin areas and consider feed-dust-extraction cyclones. Ensure the flow of ad-lib feeders is correct and that nothing is broken

• Keep well-maintained fox-fence-type electric fencing around the most vulnerable areas of your outdoor unit, i.e. the farrowing paddocks, especially if you have ad-lib feeding. Research conducted by the Food and Environment Research Agency (FERA) showed that electric fence wires should be placed at 10 cm, 15 cm, 20 cm and 30 cm intervals to be effective
• Spray weeds regularly and walk paddocks weekly to check for signs of disturbance or digging

• Other vulnerable areas include paddocks situated next to wooded areas as these could contain badger setts
• Other fencing that has greatly reduced mammalian predators in farrowing paddocks is the use of netting positioned 1 foot from the main electric fence
• Keeping badger populations away from farrowing areas is critical. If fencing is not an option, try not to straw up the farrowing arcs too long before the sows move in, as the warm, dry bedding is inviting to badgers. In addition, keep ad-lib feeders well maintained and don’t allow waste to sit in empty paddocks
• If you share any livestock vehicles with cattle producers, make sure they are washed and disinfected prior to use on the pig unit
• The Protection of Badgers Act 1992 does not grant any rights, it creates various criminal offences – it is an offence to take, kill, injure or commit cruelty to badgers or interfere with badger setts
• UV light inactivates bTB, but this is not a foolproof method of eliminating it

Bovine TB and biosecurity: introductory video from Defra

Although Defra's TB videos are aimed at the dairy sector, the content is applicable to the pig industry e.g. how to identify badger activity, routes of transmission and practical solutions to improve biosecurity.

Useful links