4) Anxiety
This may seem interesting to some but even dogs can have anxiety issues. If you notice your Shih Tzu isn't earing normally and is avoiding socialization, he or she could be stressed and anxious. You can try to get to the root of the problem by figuring out if there are any recent changes to set this off, such as moving to a new home or bringing in a new pet.
5) Dental Issues
If your pet has dental problems, eating may become painful. If he or she avoids eating due to pain, weight loss may occur. It is important to make sure that you set up a dental routine for clean teeth and gums in your pet. You also need to make sure that your pet has a dental exam and any work performed to eliminate the pain.
