A maximum of 2,000 international units (IE) may be contained per kilogram of feed with a moisture content of 12%. For adult dogs, 10IE vitamin D per kilogram of body mass per day is sufficient. If the dog is oversupplied with the vitamin, this can lead to high levels of calcium and phosphorus in the blood, vascular calcification, polyuria, bloody diarrhoea and, in the long term, kidney calcification.
Our Berlin laboratory bilacon routinely tests dog food and feed in general for numerous nutrients – thus also vitamin D.