The West Coast dairy company Westland Milk, has confirmed its decision to convert its total supply herd to A2 milk.
New Zealand dairy cows produce milk containing either A1 or A2 proteins or a combination, but there's debate over possible health risks associated with A1 milk.
Westland's acting chief executive Hugh Little, says the decision is supported by the company's farmer suppliers and does not have anything to do with the A1/A2 debate.
He says the change is because of growing market interest and demand and says it may create a niche for the company.
However, he expects the changeover could well take up to nine or 10 years.
The company will require farmers to use A2 bull semen from the start of the next mating season.