Why Puppies Should Not Drink Cow’s Milk

Nutrition & Diet 📅 August 8, 2026 👁 8188

📝 Summary

Owners wonder why puppies can drink mother's milk but not cow's milk. Most puppies get diarrhea or gastroenteritis from cow's milk—its composition differs greatly from dog milk. Here is why.

1 Why Puppies Should Not Drink Cow’s Milk

1. Why puppies cannot drink cow’s milk

1. Fragile gut: puppy guts cannot absorb milk, easily causing diarrhea; severe diarrhea may dehydrate. For hand-rearing, buy special formula from a pet store—processed to suit the gut. Even adults should not get cow’s milk; its composition hinders absorption and causes issues.

2. High lactose: cow’s milk has about half the nutrition of dog milk but more lactose; dogs do not make more lactase, so it is indigestible and other nutrients are not absorbed. So cow’s milk has little value for dogs. Dog milk is high-protein, high-fat, low-lactose; cow’s milk is the opposite—low protein, low fat, high lactose—failing puppy needs.

2. How to supplement puppy nutrition

1. Feed mother’s milk as much as possible; it best meets needs. Puppies can eat kibble after 45 days; before that, prefer milk.

2. Use fermented yogurt instead of milk; fermentation degrades much lactose, easing intolerance.

3. Use goat’s milk instead; lower lactose and rich in vitamin E, a natural antioxidant for dogs.

Puppies diarrhea from milk can be fatal if severe, so be cautious—do not give cow’s milk; find more suitable nutrition. If you have other questions, consult an online veterinarian.

Want to learn more about pet health?

Explore our pet health channel for more science-based care guides

Read More Articles →