• Both dogs and cats can be affected by diabetes.The spitz-dog and cat on a neutral background image by Ulf from Fotolia.com
  
  Diabetes results when your animal's pancreas stops producing the hormone insulin, which regulates the concentration of glucose in the blood. Animal cells need glucose for fuel, which they process into energy in the form of adenosine triphosphate (ATP), water, and carbon dioxide, maintains Dr. Alleice Summer in "Common Diseases of Companion Animals." When the glucose in your pet's bloodstream becomes concentrated, disease results, and the accompanying symptoms can be painful and deadly.
  
  

Polydipsia/Polyuria

• Veterinarians use the terms "polydipsia" and "polyuria" to refer to your pet's tendency to over-drink and excessively urinate. In diabetic animals, glucose free floats in the bloodstream without entering the cell walls and is filtered out of the body by the kidneys, ending up in your pet's urine. As the glucose leaves the body, it carries extra water molecules with it, forcing your pet to drink more water to maintain stasis (cell normality) and causing the excessive urination common to animals with this disease, says Dr. Holly Nash of PetEducation.com.
  
  

Dehydration

• Your diabetic pet may show signs of dehydration relating to the polyuria. Tacky, sticky gums, a dry nose, and skin that tents--forms a "vee" when pinched--instead of automatically becoming smooth against the body, signal that your dog or cat may need to drink more water or need an injection of subcutaneous fluids.
  
  

Weight Loss/Increased Appetite

• Due to insufficient insulin, your pet's glucose--one of its main sources of energy--remains in the blood without being transferred to the body's cells. This cell starvation causes the pet's body to use proteins and fats as energy sources, resulting in weight loss and lethargy, according to Dr. Connie Wright of Dr. Connie's Pet Care Clinic. Your pet may start overeating to compensate for the loss of food energy while continuing to lose weight.
  
  

Sudden Cataract Formation

• Diabetic dogs are more likely to develop sudden cataracts than are diabetic cats, say the veterinarians of the College of Veterinary Medicine at Washington State University. The accumulation of excess water in the lenses of the eyes can create cataracts that, if left untreated, can lead to blindness. Insulin treatment of the diabetes will not stop the formation of cataracts; typical treatment involves surgical removal.
  
  

Concurrent Complications & Conditions

• Many pets develop complications from their diabetes that may appear as separate diseases. These include an increased susceptibility to bacterial and fungal infections of the skin, bladder, and prostate gland. Other problems consist of tendencies to pancreatitis--an inflammation of the pancreas with attendant pain and vomiting--and hyperadrenocorticism, also called Cushing's Syndrome. While approximately 20 percent of diabetic dogs show hemorrhaging or tiny aneurysms of the eye retinas, eye function typically remains unchanged, states Dr. Ron Hines of 2nd Chance Pet Rescue.