Yes, dogs can drink cow's milk, but many dogs are lactose intolerant. If you decide to give your dog cows milk, be aware of how it impacts their stool and if it causes them to vomit or not. Cow’s milk contains many vitamins and minerals that could positively impact your dogs health If you decide to give your dog cows milk. However, it does have more calories and fat than oat milk, so consult with your vet as to whether it is a good idea for your pooch.