Chop celery, carrot, and parsley into small pieces.

Place raw chicken and vegetables in a pot and add enough water to cover them by 1 inch.

Bring to a boil, then reduce heat and simmer for about 30 minutes, or until the chicken is done.

Remove the chicken from the pot and shred or cut it into small pieces.

If desired, you can remove the vegetables and puree them in a blender with some of the broth then pour the puree mixture back into the pot.

Return the chicken to the pot with the vegetables.

Allow the soup to cool until it is slightly warm or at room temperature before serving it to your dog.