Puppies get all their nutrition from their moms, which means your lactating dog needs to eat for sometimes six or more. Her nutritional requirements are highest while she's nursing her pups, and her food intake must reflect that. This doesn't mean you must calculate each calorie exactly; a basic puppy food might do the trick.
Puppy food is ideal for most lactating dogs because it's higher in fat, calories and nutrients such as calcium and vitamin C that your dog needs during this physically stressful time. She is going to pass nutrients from her food onto her puppies, so using a puppy food makes sure they get the right vitamins and minerals as well. Look for puppy foods that are highly digestible, which means your dog processes the calories more efficiently.
To find the best puppy food for your lactating dog, look for those that offer the right ratios of nutrients. Veterinarian Kathleen Hefner, writing for the American Kennel Club, recommends the food be 29 percent protein, 17 percent fat and 5 percent or less dietary fiber. In addition, the food should contain DHA to help the puppies' brains and nervous systems develop correctly as well as extra calcium and phosphorous for their bone development.
Whichever food you pick, you must increase the amount of food you give your lactating dog. This is one time in your dog's life when you should consider keeping her food bowl full of dry food and letting her eat as much as she wants -- and you're likely to be surprised by the sheer volume of food she can consume. According to Dr. Hefner, you should increase her food amount by 25 percent per puppy per day. For example, if she normally eats 2 cups of food each day and has four puppies, she'll need 4 cups of food when lactating. Twenty-five percent of 2 cups is 1/2 cup, and 1/2 cup times four pups is 2 additional cups per day.
Check with your vet about the right food for you dog, and ask him about adding supplements. If your dog is already on puppy food, your vet might recommend adding a teaspoon of olive oil to the food to add some healthy fats and calories. He might also want to add calcium supplements to her diet or ask you to mix some cottage cheese with her food for additional calories and calcium.