MBD aka Metabolic Bone Disease

One of the most common nutritional ailments among lizards in captivity is Metabolic Bone Disease aka MBD.

When a lizard has MBD it does not have enough calcium in its blood.  This is due to a calcium-poor diet and a lack of UVB.  UVB exposure creates the photochemical production of Vitamin D3 from the diet.

When the lizard’s blood can’t get enough calcium from the food it eats, it starts to take calcium from the bones.  This results in the bones becoming soft. If a lizard starts breaking its bone easily it could have MBD.  Other signs include a crooked back (see photos of Frill Neck Lizard), lack of weight gain, deformities, difficulty in raising its body, muscle tremors, lethargy and the lack of ability to climb, lack of toe use and toe twitching.  The most common symptoms are the swelling of the limbs and the jaw. 

Note the crooked spine in the first photo and the missing toes in the second. This frilly kept breaking its tail at the base of its spine resulting in the animal contantly falling over on its back.  It eventually died.

IMPORTANT – MBD can occur in any lizard that is fed a poor diet and is commonly seen in insectivorous lizards that are fed nothing but unsupplemented crickets.  Juveniles and gravid females are the most susceptible.

Even though it is reversible (when caught early, sick reptiles can be nursed back to good health with veterinary treatment), it is important to remember that MBD is a PREVENTABLE disease! 

To avoid MBD in your pet reptile always apply correct husbandry practices.  These include:
- UVA/UVB Fluorescent lighting which must be replaced every 6 to 12 months
- Calcium and multivitamin powder supplements
- As varied a diet as possible according to the species

These products are all available from Reptile Trader in-store and online.

Information for this article was taken from The Biology, Husbandry and Health Care of Reptiles by Lowell Ackerman available at Reptile Trader and Murdoch University’s Reptiles; Take A Walk On the Wild Side (a veterinary handbook).