A veterinarian who works for a large dairy co-operative in the United States says Mycoplasma bovis need not cripple dairy profitability.

Dr Paul Dettloff has worked for Organic Valley Dairies, the largest organic dairy co-operative in the world, for the last 25 years. It has 2300 farms.

He will speak at a workshop organised by the Southern Organics Group in Gore on Thursday, followed by a practical session on assessing livestock at local farmer Rob Hall's property.

Mycoplasma bovis, a bacterial disease first detected in New Zealand in July last year, is widespread in other dairying countries, including the US.


Dr Dettloff said he saw farmers who did not have Mycoplasma bovis in their cows, despite being surrounded by farms with infected animals.

He coached US dairy owners on how to farm to avoid animal diseases, including Mycoplasma bovis, and emphasised the importance of optimal nutrition for production animals.

"We really have to be looking at the quality and consistency of the feed we give to calves and cows," he said.

Since the outset of the biosecurity response, 28 properties have been confirmed as being infected with the disease.

Of those properties, four separate farm blocks — owned by one farmer in Southland — had been amalgamated into a single infected property for management purposes.

Two properties had been depopulated and cleaned and the legal restrictions had been lifted.

The number of properties under restricted place notices stood at 43, MPI's latest stakeholder update said.

A workshop to discuss managing winter grazing and Mycoplasma bovis risk will be held in Milton today.