The main targets over the next five years within the new cross-border bovine TB regionalisation project include achieving a 40% reduction in reactor numbers at a traditional skin test, papers published by DAERA show.

Other targets set out in the documents include a 50% cut in new herd incidence rates and a reduction in the TB infection rate found in badgers to under 5%.

The NI side of the £10m regionalisation project is taking place across a 235-square-kilometre area running from just below Artigarvan to the shores of Lough Foyle, with its western boundary following the Irish border.

In the area, a number of interventions are planned across cattle, people and wildlife, with the initial part of the project involving a badger sett survey across farms which started in January – around 96% of farmers in the area granted permission for DAERA to access their lands.

Enhanced

The “enhanced cattle measures” employed across the five-year project include six-monthly TB testing of non-breakdown herds. Farmers will also be encouraged to slaughter cattle which previously had an inconclusive TB test, while breakdown herds will see more interferon gamma (blood) testing done.

Other measures include giving advice to farmers around sourcing replacement stock as well as biosecurity visits from private vets. Farmers who use artificial insemination will be encouraged to select bulls with improved resistance to TB, utilising the TB Advantage genetic index published by the Agriculture and Horticulture Development Board.

Wildlife

The wildlife element of the study will utilise a Test, Vaccinate or Remove (TVR) approach to badger intervention across the first two years, with “an adaptable approach” after that.

According to DAERA, the first two years will allow a baseline of TB infection among badgers to be established, with the current estimate from the department’s road traffic accident survey being that around 20% of badgers in NI have TB.

In years three and four, the department will work across “sub-areas” within the 235-square-kilometre region.

Where the data from the first two years shows a TB infection rate among badgers of below 5%, this sub-area will move to a vaccination-only intervention. Where the rate is 5 to 20%, the sub-area would remain on TVR, but in sub-areas above 20%, the plan is to inject female badgers with the contraceptive, GonaCon, while also continuing with TVR.

GonaCon is a single-shot vaccine, with trials showing it is an effective method of controlling badger populations.

In the final year, the study will revert to using TVR across the 235 square kilometres, which will enable a direct comparison with the results from the first two years.

Chipped

Badgers throughout the trial will be trapped in cages and those released will be individually micro-chipped. Test positive badgers culled using TVR will be taken to a lab for post mortem analysis.

It is also proposed to put GPS collars on a maximum of 10 badgers in one area in order to estimate territory size and interaction with badgers from other social groups.

Research

The DAERA documents make clear that this regionalisation project is effectively another research trial which will assess the effectiveness of the various interventions.

As well as reducing TB levels in both cattle and badgers, the second main aim is to “generate strong evidence about which control measures work and in what circumstances,” states the DAERA papers.