Taranaki TB hiccup timely reminder not to drop guard

“One of the big challenges is keeping people engaged,” says TBfree Taranaki committee chairman Donald McIntyre.

Incidence of the disease on-farm in most areas has plummeted thanks to concerted control efforts but it will take decades before the risk is eliminated and complacency is already creeping in, he told Dairy News.

“We’ve faced that in Taranaki for a long time… When you haven’t got it as an everyday issue you tend not to plan to counteract it.”

Despite this year’s outbreaks Taranaki is still classified as TB-free and testing of wildlife in the areas of the two outbreaks, around Inglewood and Opunake, has so far found that still to be the case, says TBfree New Zealand national disease manager Kevin Crews.

“This survey work will continue until we are confident there is no wild animal TB risk present,” says Crews.

Last week TBfree announced the first round of full herd tests on the six affected farms had also found no further reactors. McIntyre says that’s the “first step” towards ridding the herds of TB, but two successive all-clear whole-herd skin tests and a blood test are required before herds are declared free of infection.

“The nature of the disease means it can conceal itself for some time before it manifests itself in a herd,” he notes.

McIntyre says he understands the numbers culled as a result of positive tests in the Taranaki clusters have been “quite substantial” and carcase inspections found “significant numbers” with lesions.

TBfree New Zealand told Dairy News it would not reveal numbers culled, nor if any were found to be false positives (ie cattle which reacted to the skin test but following slaughter could not be confirmed as having the disease by either lesions or culturing of samples).

Neither would it say how much compensation has been paid as a result of the culls, other than saying as far as it knows all owners have been compensated in accordance with the standard 65% of the animal’s value – as determined by an independent valuer – by TBfree New Zealand. Dairy NZ is understood to top that up to 100% of the animal’s value.

Initial cases from both clusters were discovered because of lesions found in cull animals. Subsequent infections were found following trace forward analysis of movements to other herds.

“We believe the Opunake cluster could be linked to an earlier cluster from 2008, since declared clear, but investigation and analysis are continuing,” a TBfree spokesman told Dairy News.

“It is important to state that there is no suggestion any of the affected herdowners did anything other than fully comply with their obligations under the TB control programme,” he added.

McIntyre told Dairy News four farms are affected in the Inglewood area, and two near Opunake. Three of the Inglewood farms have family ties with movement of stock between the farms.

The clear tests have been a relief for the affected farms, he adds. “Having an infected herd is extremely stressful…. The co-operation and support of the Taranaki farming community in helping the TB control programme stay on top of the herd infections has been greatly appreciated.” 

All affected herds are subject to movement restrictions until they record two clear tests, six months apart. Farms within a 10km radius of the infected farms are now on an annual testing regime “as a precautionary measure” to pick up any potential residual infection as quickly as possible, says TBfree.