Why do this?
Infected cattle can excrete M. bovis in their dung. Cattle manure/slurry may therefore be contaminated with M. bovis. Measures can be taken to minimise the risk of manure being a source of TB for your cattle.
How to reduce your risk
Store manure for a long period before spreading on your farm
Research has shown that M. bovis can survive in manure for up to six months. With this in mind, it is recommended to store manure for at least six months, before spreading on pasture so that few, if any, M. bovis bacteria will be present at the time of spreading. Manure should be stored in a secure structure that is inaccessible to domestic and wild animals.
Only spread manure on arable land or pasture that is not going to be grazed by cattle for at least two months
This minimises the risk of infecting cattle from manure even further, in addition to the lengthy storage period recommended above, by avoiding direct contact of contaminated manure with cattle. The two month waiting period should also apply to grass if it is to be cut for forage.
Minimise aerosols and contamination of roadways when spreading
Aerosols of manure may promote spread of M. bovis bacteria. Ideally spreading methods should allow for controlled application and spreading should not be carried out in windy weather. If the spreading method generates aerosols that cannot be controlled, then it increases the risk of spreading infection into fields that contain cattle.
Don’t spread manure from other farms
The TB status of other farms is not always known at the time that manure is collected. Purchasing manure from other farms increases the risk of purchasing infectious agents from those farms, including M. bovis.