They help you determine which dewormer to use.

Test all your pets once a year, or when ill. Test new pets or puppies, birds, reptiles, etc. (especially those your family members handle).

Worms are extremely common and many times lead to death. Always test one month after deworming. Easy, just collect 1 to 2 teaspoons and mail it in. Highly accurate, speedy resulting within 24 hours.