The principal physiological role of vitamin D in all vertebrates is in calcium and phosphorus homeostasis. The classic clinical deficiency syndrome is rickets. The FEEDAP Panel notes that for turkeys for fattening, equines, bovines, ovines and pigs the maximum content for vitamin D3 in feed does not provide any margin of safety, and that, except for pigs, the maximum content is above the upper safe level, according to National Research Council data when animals were fed a supplemented diet for more than 60 days. No safety concern was identified for the use of vitamin D3 in chickens for fattening and fish. Not withstanding the long history of supplementing compound feed with vitamin D and the absence of publicly reported intolerances, the FEEDAP Panel is not in a position to draw final conclusions on the safety of vitamin D and considers the current maximum contents as temporarily acceptable. Any additional administration of vitamin D3 via water for drinking represents a safety concern. Current nutritional surveys in 14 European countries showed that vitamin D intake is sufficiently below the upper safe limit. The FEEDAP Panel assumes that foodstuffs of animal origin were produced following current production practices, including vitamin D3 supplementation of feed and concludes that the use of vitamin D in animal nutrition at the currently authorised maximum dietary content has not and will not cause the tolerable upper intake level to be exceeded. Vitamin D3 is not an irritant to skin and eyes and is not a skin sensitiser. Inhaled vitamin D3 is highly toxic; exposure to dust is harmful to persons handling the additive. No risk to the environment resulting from the use of vitamin D3 in animal nutrition is expected. The vitamin D3 under application is regarded as an effective dietary source of the vitamin in animal nutrition.