Related Experiment Video
Updated: Aug 6, 2026

Studying Chronic Exposure of Mice to Ultraviolet B Radiation
Published on: August 19, 2025
Effects of UVB radiation on calcium metabolism in psittacine birds
1Birch Heath Veterinary Clinic, Birch Heath Road, Tarporley, Cheshire CW6 9UU.
Abstract:
The effects of providing ultraviolet (uv) radiation (285 to 315 nm, ultraviolet B) on calcium metabolism in two groups of 20 healthy grey parrots (Psittacus e erithacus) fed either a seed or pellet-based diet were investigated. There was a significant increase in the concentration of ionised calcium in the plasma of both groups, independent of the calcium and vitamin D(3) content of the diets fed, and a significant increase in the plasma concentration of 25-hydroxycholecalciferol in only the seed-fed group. In a separate study there were no significant increases in plasma ionised calcium or 25-hydroxycholecalciferol between March and August in a group of 28 South American parrots (Pionus species) exposed to unfiltered natural sunlight.
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