UV-B lighting is essential for vitamin D3 synthesis in most diurnal reptiles. Inadequate UV-B provision is one of the most common and preventable welfare failures in reptile keeping.
Metabolic bone disease from inadequate UV-B provision causes progressive suffering: soft, deformed bones that fracture spontaneously, difficulty walking, and in severe cases, spinal cord compression and paralysis. The condition develops slowly — often over months before clinical signs are apparent — meaning many reptiles suffer significant physiological damage before the problem is recognized. MBD is almost entirely preventable with appropriate lighting that matches species-specific UV-B requirements. The welfare failure is compounded by pet trade education that frequently provides inadequate guidance on UV-B requirements. Informed reptile keeping starts with species-appropriate UV-B provision as a non-negotiable welfare baseline.