Mycoplasma bovis: Research to look at milk yield impact

Photo: RNZ / Richard Tindiller

By Maja Burry of RNZ.

The Ministry for Primary Industries is commissioning new research into the impacts of Mycoplasma bovis on cattle in New Zealand.

Scientists at Massey University would undertake the one-to two-year study, where they would look at the symptoms of the cattle disease, the effects on milk yield and composition and the duration of these effects.

MPI chief science advisor John Roche said the work would help accelerate eradication of the disease from New Zealand farms and minimise the negative impacts.

"The results of this project will contribute evidence to help in the detection of M. bovis, improve our surveillance tools, and increase our understanding of how the disease spreads under different New Zealand farming systems, which is key in terms of eradication," Dr Roche said.

Dr Roche said the vast majority of research into M bovis had been done overseas and had largely focused on cattle kept in barns or on feedlots, which were different to New Zealand's pasture-based farming system.

"Very little was known about it [M bovis] in the pasture setting and as we get closer and closer to eradication, as we get down to lower numbers of animals, it's really important we understand how the disease impacts on individual farms... to help us find those last farms. "

Since 2017, when M bovis was first detected by MPI, 238 farms have tested positive but only 31 of these are classed as actively infected. As part of the biosecurity response, 141,677 cattle have been culled.

Only properties already known to be positive for M bovis would be used for the research and these farms will only be studied up until agreed dates for cattle depopulation, Dr Roche said.

New Zealand is the first country in the world to attempt to eradicate M bovis, a bacterial disease that can cause animal welfare and productivity issues, particularly in dairy cattle, including mastitis that doesn't respond to treatment, severe lameness and late-term abortions.

MPI said the cost of the study was commercially sensitive, but it said the M bovis programme had allocated up to $30 million for research projects into the cattle disease.

- RNZ