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.
Nutrients are divided into subcategories: protein, carbohydrates, fats, vitamins and minerals, and water. Regular brushing and professional cleaning can keep your dog’s teeth healthy and gleaming. Giving your pet appropriate toys to chew prevents fractures.
Common dog food protein sources include meat, poultry, fish, and some plant ingredients, such as corn gluten and soybean meal.
Protein is best known for supplying amino acids to build hair, skin, nails, muscles, tendons, ligaments, and cartilage. It also plays a main role in hormone production.
Dogs, best fed as carnivores, require essential amino acids that are not all found in the proper balance in single plant protein sources such as soybean meal.
Common carbohydrate sources are plants and grains. Carbohydrates, also categorized as starches (sugars) and fibers, provide energy and bulk, respectively.
Starches are made up of various types of sugar, such as glucose or fructose. Through digestion, dogs can easily convert sugar into usable energy.
Fiber may or may not be fermented or broken down into short-chain fatty acids by bacteria in a dog’s intestines. Highly fermentable fiber sources, such as vegetable gums, provide high amounts of short-chain fatty acids. Moderately fermentable fibers, such as beet pulp, provide short-chain fatty acids and bulk for moving waste. Slightly fermentable fibers, such as cellulose, provide mainly bulk for moving waste through the digestive tract and only a few short-chain fatty acids.
Water is the single most important nutrient for the body. Without it, the body cannot transport nutrients, digest nutrients for energy, regulate temperature, or eliminate water.
Fats are found in meats, poultry, fish, and plant oils. Fat, for all its bad press, fulfills many vital body functions. Animal cell membranes are made of fat. Fat also helps maintain body temperature, control inflammation, and more. Fat is the primary form of stored energy in the body, providing twice as much energy as carbohydrates or proteins.
Fats also have been shown to be important in blood clotting and managing inflammation.
Vitamins are responsible for aiding functions such as bone growth, blood clotting, energy production, and oxidant protection. Vitamins A, D, E, and K require fat for absorption into the body, while vitamins such as the B-complex vitamins and vitamin C need water to be absorbed into the body.
Minerals provide skeletal support and aid in nerve transmission and muscle contractions.