While a puppy’s first food is her mother’s milk, once weaned, she no longer needs milk in order to thrive. “Just like in humans, dogs lose their ability to digest lactose as they age due to decreased production of a digestive enzyme called lactase,” Barrack explains. “As they grow, different dogs (and people) are able to tolerate dairy well, while others cannot.”
Puppies are born with higher levels of lactase, the enzyme needed to break down the sugars in milk, but those without access to their mother’s milk should never be given cow’s milk as a substitute, explains Barrack, as cow’s milk is higher in lactose than a dog’s.
If your dog suffers from a degree of lactose intolerance, the signs will be all too clear. Pups with difficulty digesting dairy may experience gastric issues including abdominal pain, gas, bloating, nausea, vomiting and diarrhea. Unfortunately, there are no dog-friendly lactose intolerance medications to help your pup with these unpleasant symptoms.