A2 is a type of protein. In the U.S. , the most popular dairy breed has become the Holstein. She is a big effecient producer. She is NOT an A2 producer. It is the old breeds ,that are also smaller, like Jersey, that is A2 dominant. Most of tge European dairy breeds are still the local breeds not tge Holsteins.

Making the milk into yogurt removes much of the lactose. And by starting with fluid milk, it must have D3 added.