A new scientific paper has documented cases of fur seals passing a strain of bovine tuberculosis to New Zealand beef cattle.
Over the last 20 years there have been seven documented cases of cattle catching a strain of Tb after coming into contact with the fur seals, three on beaches in the North and South Islands and four in the Chatham Islands.
TBfree New Zealand national disease manager Kevin Crews says the purpose of the paper was to document the cases, which are believed to be the only ones recorded in the world.
He says over a 20 year period the bovine Tb control programme, which covers cattle and deer, has had incidental findings of bovine Tb which are mostly unexplained, but when DNA or genetic typing has been used they've been shown to be cases that have been derived from seals.
Mr Crews says in each case only a single animal from each farm had caught Tb and there's no evidence that cattle can pass that strain onto other cattle.