MPI gives seven possible reasons for cattle disease in New Zealand

Plans have been announced to cull 22,000 cattle by June. Photo/Brett Phibbs.

The serious dairy and beef cattle disease Mycoplasma bovis could have entered New Zealand through seven potential pathways, one of which is imported veterinary medicines and biological products, says biosecurity watchdog, the Ministry for Primary Industries.

The ministry last night released three reports on the disease, the spread of which the ministry aims to contain through the cull of more than 22,000 cattle before June 1.

Two reports examine the response to the disease being identified in New Zealand for the first time last year and the third examines potential entry routes.

According to a covering statement from the ministry, these are imported live cattle, other imported animals, imported frozen semen, imported embryos, imported veterinary medicines and biological products, imported feed and imported used farm equipment.

The report does not reach any conclusion about the likelihood of any of the seven risk commodities being responsible.

However, throughout the pathway report, all mention of imported veterinary medicines and biological products are redacted, or blacked out.

Speculation in the rural sector that the ministry was focusing on this pathway firmed this week with the news warranted investigators had searched three properties – one in the North Island and two in the South Island – in action "related to potential breaches of legislation related to the M Bovis response".

The ministry would not comment on the searches.

An MPI spokeswoman last night would not say what information had been redacted or why and declined to respond to questions about whether MPI was focusing on veterinary linked treatments involving livestock as part of its investigations.

In a diagram of the seven potential entry points in the pathways report, veterinary medicines and biological products were redacted.

The Herald has seen an unredacted copy of the same diagram, which was circulated in the farming sector earlier which shows the words blacked out were veterinary medicines and biological products.

Sources said the searches were in Auckland and Southland and veterinary properties have been visited by investigators.

Herald inquiries in the veterinary sector suggested it was possible biological material associated with bovine mating and reproduction could carry MBovis. Bovine embryo implants are usually performed by vets.

The released reports also raised a red flag about MBovis infection risk from imported frozen semen and embryos, citing "knowledge gaps" about the risk and recommending research funding to better understand the transmission risk.

MBovis is well-established in the herds of New Zealand's trading partners and other countries. New Zealand is the first country in the world to try to eradicate it before it is established by a mass cattle cull. The disease, while debilitating to cattle and more obvious when they are under stress for example during calving, has been declared harmless to humans, with meat and milk from affected animals safe to consume.