Tackling TB: 8,649 contiguous herd tests conducted so far in 2020

A total of 8,647 contiguous herd tests have been conducted so far this year, according to the Department of Agriculture, Food and the Marine.

In a statement to AgriLand, a spokesperson for the department said:

“There were 8,649 contiguous herd tests with 724,134 animal tests since the start of the year giving an average herd size of 84.”

This includes herds that may have been tested under the contiguous programme more than once, as the contiguous programme runs until the index herd tests clear, it was noted.

751 of these herd tests were positive giving a herd incidence of 8.68% – which is more than double the national herd incidence across all tests combined. 3,000 reactor animals were disclosed as part of these tests.

“Contiguous tests accounted for 30% of all breakdowns initiated following a positive test. These figures underpin the value and importance of the contiguous testing programme in the eradication of TB,” the department spokesperson said.

What are contiguous herd tests?

Following the disclosure of reactors in a herd and the subsequent categorisation of the breakdown as “high risk”, notifications are issued to all neighbouring (‘contiguous’) herds bordering the land parcel where the reactors were located and/or where they are likely to have become infected, according to the department in its 2018 overview of Ireland’s Bovine TB Eradication Programme.

After being notified, a contiguous testing programme is undertaken in those herds on a four-monthly cycle until infection is no longer detected in the breakdown herd.

The contiguous herds, if not tested already in the previous four months, are restricted from moving animals out pending the completion of the first test in the cycle.

The restriction on these herds is lifted once the herd passes the test. This ensures that all efforts are made so disease in the neighbourhood is identified and prevented from spreading further, the department concluded.