Vitamin D Toxicity

Etiology:  High vitamin D levels from consumption of misformulated laboratory diets result in excessive calcium absorption and mobilization (dystrophic mineralization).

Incidence: Incidence of vitamin D toxicity is low in laboratory rabbits.

Incidence:  Hypervitaminosis D is the most commonly seen toxicity.

Clinical signs: Clinical signs include anorexia, teeth grinding, and weight loss.

Pathology:  Mineralization of the endothelium and media of muscular arteries (especially the aorta), gastrointestinal smooth muscle, glomerular capsule, tubules, and renal vasculature is seen.

Diagnosis:  Diagnosis can be made by detection of high serum calcium levels, and by observation of gross and histologic lesions.  Levels of D3 in the feed can also be measured.  Vitamin D levels above 2000 IU/kg are suggestive of toxicity.