QUESTION: How can I tell if my dog, Toni, is developing cataracts? His eyes are starting to look cloudy, and I'm afraid he may need surgery. What should I do?ANSWERS: A cataract, which is technically an increased opacification and calcification of the lens in the eye, can occur at any age.Puppies and kittens can be born with congenital cataracts, and dogs can develop cataracts as a result of diabetes.However, most cataracts are senile cataracts that develop in older pets, usually 10 years of age and older.Particular breeds, such as poodles, cocker spaniels and other small breeds are more commonly affected than other breeds.While various herbs and homeopathics might slow down the growth of cataracts and are always worth trying, in cases of severe cataracts (mature or hypermature cataracts), surgery is usually necessary to restore vision.A much more common problem in older pets is called nuclear sclerosis. In this condition, the lens starts to look a bit cloudy. However, vision is not interfered with, and the condition does not progress.Usually, your veterinarian can tell the difference with a simple ophthalmic examination. In a darkened room, a light is shined through each lens. If the light reaches the back (retina) of the eye, the diagnosis is nuclear sclerosis. If the doctor can't see the retina, then a cataract is diagnosed and more testing can be done if needed.Dr. Shawn P. Messonnier, author of the "8 Weeks to a Healthy Dog" and "The Natural Health Bible for Dogs & Cats" is a veterinarian and pet care advocate. Write him at 2145 W. Park Blvd., Plano, TX 75075, or e-mail naturalvet@juno.com