First Five Weeks

• A newborn shih tzu puppy is blind, deaf and fits in an adult's hand. The ears open at 14 to 17 days. Between two to four weeks, the puppy opens its eyes and its vision improves gradually. It learns to play and interact with other canines during this period. For the first four to five weeks of your shih tzu puppy's life, it should stay with its mother and the rest of the litter.
  
  

Five to Fourteen Weeks

• The shih tzu puppy begins to wean and explore its surroundings during this time period. The body of the puppy at this stage is changing and growing rapidly, so it needs a lot of food. High-quality commercial puppy foods should be able to meet its nutrient requirements. A growing shih tzu puppy should eat about five to ten percent of its body weight per day, divided into three feedings.
  
  

Fourteen Weeks to Six Months

• At 14 weeks, a shih tzu puppy's permanent teeth begin to grow. It may experience some discomfort and pain. You can help your puppy by providing hard bones or teething dog toys for it to gnaw on, otherwise it will chew on something else.
  
  

Six Months to One Year

• At this stage, your shih tzu puppy slows down its growth and has less energy intake requirements, so you can reduce the amount of food you feed it. Also, a shih tzu usually becomes sexually mature during this stage of development. If you are not planning to breed it, you should consider spaying or neutering it, which has health and behavioral benefits. You will spare yourself the mess of female dog menstruation and male dog spraying. Spaying or neutering is also better for your puppy, as it will have lower risks of getting mammary or testicular cancer. In addition, you will not be responsible for accidental shih tzu puppies ending up in animal shelters.
  
  

One Year to Eight Years and Older

• A one-year-old shih tzu is considered an adult dog. At this time, you should switch to a high quality adult dog food, which can be purchased at a pet store or, in some cases, at your vet's office.
  
  

Eight Years and Older

• At eight years old, your shih tzu is considered a senior dog and its diet should again be changed. You can get food specially formulated for older dogs at your local pet store or, in some cases, your vet's office. You should also increase the frequency of your visits to the vet.