pets with colitis strain to defecate and may have flecks of blood or mucous associated with it but they still are active and have high energy levels.  If your pet experiences loss of appetite, feels lethargic, and passes stool of a watery consistency, you should contact your veterinarian immediately. The major cause of colitis is associated with dietary intolerance and parasitic infections while other include inflammation due to foreign bodies or tumor. Overt symptoms are taken into account to make the diagnosis. For further and thorough examination, a veterinarian may perform fecal testing, blood tests and make use of imaging techniques like x-rays and abdominal ultrasound. This helps in detecting the underlying cause of the disease if any. If the underlying cause is not found, antibiotics and deworming treatment is suggested along with nutritional support to aid in the recovery process and support digestive health.