Friday, April 27, 2018

Metabolic Bone Disease- a quick refresher

Today's Lesson--

Here is a side by side comparison of two monitor lizard x-rays. The one of the left is the Nile monitor that the vet & I chose to euthanize yesterday; the one of the right is a random x-ray off the internet. Notice the difference in the bones?



Solid, dense, calcium-stable bones almost glow on x-rays. You can see their distinct edges and patterns. MBD bones are hollow, pitted, and almost invisible because of the lack of calcium.

There are parts of the Nile's x-ray where you cannot see his spine through because of the shadows of internal organs. But the sad thing is that the organs are *under* the spine. Under! And you still can't see it. You can also see multiple fractures and curves in the spine and legs that never would have healed.

Here's the hellish part about MBD-- a lizard's body MUST have calcium in its blood supply to survive. If there is not enough calcium being metabolized (coming into the body through the food and then converted into usable calcium through sunlight or adequately powerful UVB), the body will steal calcium from the bones. The bones start becoming weaker and weaker until they are rubbery like Jell-O. When they are that weakened, simple touching and holding will snap jaw bones; a small fall will shatter joints; a leg that is caught and then pulled loose will disintegrate.

A reptile must have enough digested calcium through high calcium foods (whole rat/mouse bodies, high calcium greens, or gut loaded & dusted insects). But all the calcium in the world will NOT prevent MBD if there is no way to absorb it. In the absence of direct sun, a UVB light is a necessity. It must be 18 inches or less above the area where the lizard is the most. It also needs to cover the majority of the area of the basking spot. The problem with coil UVB bulbs is that their radius is very small and often in a different place than where the lizard is. You can combine heat & UVB with a mercury vapor bulb or you can buy a long UVB tube to run the length of the tank.

MBD is a hellish way for a lizard to die. Some pet stores will call it "Cage paralysis" because a reptile loses the ability to control its limbs. It is painful because of frequent breaks and fractures.

PLEASE DO YOUR RESEARCH! Preventing MBD is FAR easier than trying to correct it. All the reptiles I have ever rescued with MBD who actually survived it had a significantly shorter lifespan.