Pregnancy and nursing are not only responsible for many changes in a dog's body, but for changes in her lifestyle as well. If your dog is pregnant or nursing, pay special attention to her changing nutritional needs as she carries, delivers and nurses her puppies.
If you're planning to breed your female dog, it’s important to assess her body condition well in advance of breeding. Because of the physical demands of pregnancy and nursing, a dog with less-than-ideal health can experience problems:
Be sure to feed the proper amounts of a complete and balanced diet. This will support the mother's healthy weight and body condition before breeding and help maintain her health and that of her babies throughout pregnancy and lactation.
The gestation period for dogs is nine weeks. Pregnant dogs gain weight only slightly until about the sixth week, and then gain weight rapidly.
The energy requirements of pregnant dogs are reflected in the pattern of weight gain. Pregnant dogs will need to consume 25% to 50% more than their normal food intake by the end of pregnancy, but energy requirements do not increase until about the sixth week.
The best diet for pregnant and nursing dogs is a high-quality, nutrient-dense pet food formulated for all life stages or for growth. Although puppy diets are generally recommended for pregnant or nursing dogs, large-breed puppy formulas may not be appropriate for this use due to their adjusted energy and mineral content.
Pregnant dogs lose weight after giving birth, but their nutritional needs increase dramatically. Depending on litter size, nursing dogs might need two to three times their normal food requirement to nourish their pups. Be sure your nursing mom has plenty of water so she can generate the milk volume she needs to feed the litter.
To help your nursing dog get enough nutrition, you can try several tactics:

By four to five weeks after birth, most puppies are showing an interest in their mother’s food. Gradually, the puppies will begin eating more solid food and nursing less. At the same time, the nursing mother will usually begin eating less. Most puppies are completely weaned around age 7 to 8 weeks. By this time, the mother's energy requirement is back to normal, and she should be eating her normal pre-pregnancy diet.
Your new puppy's first meals at home are very important. Find out what formula your puppy has been eating, and continue feeding this food for a day or two after you bring him home. If you want to change his diet to a premium food such as IAMS™ ProActive Health™ Smart Puppy Original , gradually move him to the new formula and help avoid intestinal upsets by using the following steps:
Day 1: Fill your dog's bowl with 75% of his old food and 25% of IAMS ProActive Health Smart Puppy Original.
Day 2: Mix his former food and IAMS ProActive Health Smart Puppy Original in a 50/50 ratio.
Day 3: Feed your dog a mixture that's 75% IAMS ProActive Health Smart Puppy Original and 25% former food.
Day 4: Feed 100% of IAMS ProActive Health Smart Puppy Original.
To feed a puppy from weaning to 4 months of age, offer a 100% complete and balanced premium puppy formula. To determine each serving size, start with the daily amount recommended by the feeding guidelines on the pet food label, and divide that number by the number of times a day (usually three times) you plan to feed your puppy.
Serve the food at room temperature and remove the bowl within 30 minutes after he's done eating. After four months, you can feed a puppy twice daily on a regular schedule.
Don't add nutritional supplements to your dog's diet. Adding commercial dietary supplements or 'people food' such as hamburger, eggs, cottage cheese, or cow's milk is unnecessary and might even do more harm than good.