Dear Dr. John,

I have two turtles, ages 55 and 35. They have been healthy for almost their entire lives. I’ve never had to take them to the vet but recently, one of them developed a hole in their carapace on the underside. I made some calls but not many vets treat turtles. I tried to do some research to look for possible cases but more importantly to try and repair the defect. Do you have any suggestions as to likely causes and what I should do? Also, my nephew has a cat that has had only dry food for 10 years. Is this adequate? The cat seems underweight to me, so I ask. J.N.

Dear J.N.,

The most common causes for turtle shell defects are trauma, bacterial or fungal infections, poor hygiene sometimes caused by stagnant dirty water, and nutritional deficiencies mostly due to insufficient Vitamin D3 or calcium in the diet. There are veterinarians that specialize in herpetology and exotics, and I would look into nearby veterinary schools such as Tufts or any wildlife centers. They should be able to see your turtle and make a diagnosis and set up appropriate treatment.

I would urge you not to take matters into your own hands and let the veterinarian set up a repair of the shell defect. Typically, one uses epoxy with a fiberglass mesh. The epoxy best suited to this kind of repair should be waterproof and biologically compatible. Agents needed for infection may also need to be applied beforehand or simultaneously. There are also some commercial products on the market that can be used. It is important to address the situation and not let it fester.

As for the cat, dry foods are excellent sources of a well-balanced and nutritious diet if they are from quality manufacturers. There is no need to change the diet, and it is better when it comes to promoting better dental health as the cat ages. If the cat seems underweight, I am sure their veterinarian would take appropriate steps to diagnose any disorder or cause of any weight loss, perceived or real and treat as necessary. Good luck.

Dr. John de Jong is President of the World Veterinary Association. He owns and operates the Boston Mobile Veterinary Clinic and can be reached at 781-899-9994.