Department confirms TB rule change with clampdown on inconclusive animals

The Department of Agriculture, Food and the Marine has confirmed rule changes regarding TB testing, which will see animals with inconclusive results removed from the herd.

In addition, herds with four or more animals testing inconclusive will be deemed reactors, a spokesperson for the department confirmed to AgriLand today, Thursday, June 18.

In a statement, which confirmed commentary on the matter from the Irish Farmers’ Association (IFA) earlier this week, the department said:

The revised internal management guidance for TB herds is that when a breakdown occurs, cattle which previously tested inconclusive within the herd should be removed as in-contacts with compensation payable, and that when four or more inconclusives are disclosed at a herd test, they should be deemed reactors with compensation payable.

“This change is an update to internal management guidance for TB herds,” the statement said.

Explaining its reasoning for the rule change, the department said:

“Approximately 2,000 cattle per year test inconclusive to the TB skin test.

It is estimated that around 20% are truly infected, going on to spread TB.

“As disease progresses, they may repeatedly retest falsely negative due to immunosuppression caused by TB – yet continue to silently spread disease within the herd.

“Since 2012, inconclusive cattle have been confined to the herd of disclosure and cannot move, other than to slaughter.

“Herdowners are strongly advised to cull these cattle as they present a significant risk of future breakdowns.

Those which are not culled are often implicated in subsequent breakdowns – for example, 21% of herds with inconclusives which retested negative in 2013 had a breakdown in the next three years.

“Too many herds are retaining these high-risk animals. Approximately 33% of all herds with TB will experience a repeat breakdown within five years, with undetected residual infection within the herd a major driver of this,” the department said.

TB Stakeholders Forum

The Department of Agriculture noted that the TB Stakeholders Forum recommended additional measures on inconclusives such as blood testing and removing them.

This recommendation, along with others from the TB Forum, is informing the development of a new TB strategy.

Stakeholders’ submissions to the TB forum included a request to remove animals deemed higher risk following a TB breakdown to avoid future breakdowns in the herd, the department added.

Revised guidance

Continuing, the department said: “The Department of Agriculture, Food and the Marine internal guidance for managing TB breakdowns had included instructions that when a breakdown occurs, the removal of high-risk animals should be considered, such as older inconclusive animals.”

This, it was added, is “in order to reduce the risk of the infection being spread undetected from inconclusives which have TB but are immunocompromised and thus test falsely negative”.

Outlining the changes to the guidance, the authority added:

TB outbreaks are a significant burden on affected herds and the objective of public policy in this area is to avoid such occurrences.

“This modification is necessary to reduce the risk of a recurrence of the disease in affected herds, and the risk of spreading the disease to the more than 96% of herds that are clear.

“Stakeholder organisations were informed of this change as part of our ongoing communications with them,” the department concluded.