Health – UVB and Supplementation
The option to provide or not provide UVB lighting to monitors in general has been a longstanding debate. We often hear many keepers swear by only providing whole foods and not needing UVB, and other keepers swear their monitor simply “does better” with UVB lighting. To stay out of the realm of opinion and even experience, we try to confine discussion to biological fact.
What is not debatable is that monitors, like many living things, require calcium. To metabolize and process ingested calcium, the monitor requires vitamin D3. Lack of absorbed calcium can result in Metabolic Bone Disease, often abbreviated to MBD.
Where and how the monitor receives calcium and D3 is the keeper’s choice, and from that choice stems the neverending debate as to which way is best.
Monitors can ingest calcium in several ways. One is through the skeletal systems of ingested vertebrate prey, such as rodents. Since the Savannah Monitor is an invertebrate feeder and therefore does not ingest skeletal systems, it will ingest calcium in prey items such as the shells of land snails, which are made up of calcium carbonate. For a Savannah Monitor in captivity whose diet is comprised mostly of insects, powdered calcium supplementation may be needed depending on which insect is chosen.
Monitors can receive vitamin D3 in two ways. Being diurnal lizards, monitors in the wild have their production of vitamin D3 triggered by natural UV lighting from the Sun. Many keepers provide UVB lighting in captivity to also trigger the production of D3. If no UVB lighting in captivity is provided, a powdered calcium supplement can be chosen that contains vitamin D3.
Again, it is the keeper’s choice. Monitors with no UVB lighting will receive D3 from supplementation, and monitors with UVB lighting will not need D3 in the powdered supplement.
Back to the realm of experience, for young monitors feeder insects can be lightly dusted with calcium powder for most feedings throughout the week and lightly dusted with calcium/D3 combination powder for 2 days per week. As the monitor gets older, supplementation can drop to several times per week, with one dusting of calcium/D3 combination powder per week 1.