Have your say on badger culling as a method of controlling cattle TB

The Coalition Government plans to include badger culling in areas of high and persistent cattle TB incidence as a component of its bovine TB control programme.

The Coalition Government plans to include badger culling in areas of high and persistent cattle TB incidence as a component of its bovine TB control programme.

Defra had made clear that “The main body of evidence on the impact badger culling has on incidence of bovine TB in cattle is the Randomised Badger Culling Trial (RBCT).” However, the planned culling differs from that undertaken in the RBCT in important ways including (a) there is no requirement for culling across large areas to be simultaneous; (b) the culling methods will include the shooting of free-ranging badgers as well as cage trapping and shooting; and (c) farmers and landowners will be licensed to cull badgers. In the RBCT, culling was conducted simultaneously using only cage trapping and shooting by experienced government staff.

Defra has launched a consultation seeking everyone’s views on these plans by 8 December 2010. Please see the website to read about the approach.

MRC Centre researcher Professor Christl Donnelly helped design, oversee and analyse data from the RBCT, a large-scale field trial that was undertaken in 1998 by Defra to assess the effectiveness of badger culling. The results showed that although the incidence of cattle bTB reduced during culling and in the first years after the final cull, these reductions subsequently declined.

Professor Donnelly said: "Bovine TB is a big problem in Britain and the disease can profoundly affect farmers' livelihoods. We know that bTB is transmitted between cattle and badgers, so the Randomised Badger Culling Trial was set up to find out if culling badgers would help control the spread of the disease. There has been some controversy over badger culling as a bTB control method and it has been unpopular with the general public.

In the RBCT, ten areas of 100 square kilometres were subjected to badger culling, and compared to ten similar areas with no culling. Culls were repeated annually and ended in October 2005. Previous analyses have shown that during the cull, bTB incidence in cattle within the cull zones decreased, whereas disease incidence in cattle outside cull zones increased, offsetting the benefit.

The most recent analysis of the RBCT data (up to July 2010) shows that after the culling finished, the number of infected herds inside cull areas was on average 34% lower than the number of infected herds in non-cull areas (in the period from 1 to 5 years after the final culls). The results also show that this benefit diminished over time after the culling ended. The research also shows that since the culling finished, the number of infected herds in two kilometre zones outside cull areas was comparable to the number of infected herds in areas outside non-cull areas.

Find out more information about the bovine TB research undertaken at the MRC Centre for Outbreak Analysis and Modelling.