As soon as I ran out of formula once Tara was one I put her on cows milk. The first couple of bottles she didn't take it all as I think she wasn't used to the taste but after that no problems at all.

As she was on lactose free formula I transitioned her to lactose free cows milk for about 3 weeks and then swapped her over to normal full cream milk and she has had no problems at all. I also found that when she had her bottle in the evening it seemed to make her sleep longer overnight as it must have filled her up more.