Hypervitaminosis D

Question 1

What point is important in cats regarding vitamin D

Answer 1

Cats are unable to convert the precursor of vitamin D in the skin via UV radiation
- this is due to high levels of an enzyme in an alternative pathway that converts the precursor of vitamin D to cholesterol rather than pre-vitamin D
- as carnivorous prey diet has adequate amount of vitamin D, pathways for synthesis would be unnecessary

Question 2

What are the main causes of hypervitaminosis D

Answer 2

Unnecessary supplementation with vitamin D of a complete diet

Manufacturing errors

Ingestion of vitamin D-containing rodenticides

Question 3

What are the clinical signs for hypervitaminosis A

Answer 3

Acute disease:
- hypercalcemia
- PUPD
- muscle fasciculations or seizures
- vomiting, diarrhea, anorexia
- acute renal failure

Chronic disease:
- musculoskeletal deformities (rare)