Dry Kibble

• Dogs who need to gain weight should be fed a premium dog food that contains real meat. Check the first five ingredients to see if it lists chicken, beef, venison, lamb or turkey without the words "meal" or "byproducts" after the meat name.
  
  

Canned Food

• Canned dog food, when coupled with dry kibble, can help a dog to gain weight. Canned food usually contains more meat and water than dry kibble, and it is easier to digest, which makes it optimal for weight gain.
  
  

Natural Proteins

• Chicken, eggs, rabbit, fish, beef and tripe are good sources of protein that are easily digested by dogs. If you opt to feed your dog chicken, debone it before mixing it with the dog food to avoid possible puncture wounds to the dog's esophagus, intestines and stomach.
  
  

Vegetables

• Peas, zucchini and green beans are ideal vegetables to serve to your dog. Onions, garlic, broccoli and cauliflower should be avoided, since these can negatively affect the dog's health and are common allergens.
  
  

Carbohydrates

• Brown rice, millet and whole-wheat pasta are good sources of carbohydrates for a dog's diet. However, when trying to get your dog to gain weight, these items should account for no more than 20 percent of its total diet.