X-rays, barium studies, ultrasound, and endoscopy. Again, because your pet can not talk to us, a complete diagnostic evaluation will help rule out many of the underlying causes of gastrointestinal diseases. For example, if your veterinarian suspects a tumor or foreign body blockage, he or she may order an x-ray. If a more direct view is needed, your vet may recommend an endoscopic exam in which the practitioner uses a flexible scope with a fiber-optic light source to directly view digestive organs from inside the animal's body and look for ulcers, tumors, and foreign bodies. Also, microscopic evaluation of tissue samples taken during endoscopy.
Biopsies also help veterinarians determine if a tumor is benign or malignant.
Biopsies can also assist in diagnosing if a bacteria or allergies are the cause of the GI disease. If the liver or other organ is suspected as the primary disease causing the digestive disturbance, an ultrasound may be recommended. The treatment your veterinarian recommends will, or course, depend on the diagnosis. A short course of medication usually does the trick for intestinal parasites. If tests show an abnormal proliferation of bacteria in the gut, antibiotics may be the treatment of choice.