Dunlin (Calidris alpina) - A medium-sized shorebird with a drooping bill, adult dunlin can be easily recognized while in breeding plumage by the large black patch on their otherwise white bellies. Familiar around the world, dunlin spend their winters up and down coastlines across the entire Northern Hemisphere.
Preformed vitamin A is found in animal products such as meat, fish, poultry and dairy foods. The other type, pro-vitamin A is found in plant-based foods such as fruits and vegetables. The most common type of pro-vitamin A is beta-carotene.
Two forms of vitamin A are available in the human diet: preformed vitamin A (retinol and its esterified form, retinyl ester) and provitamin A carotenoids [ 1-5 ]. Preformed vitamin A is found in foods from animal sources, including dairy products, fish, and meat (especially liver).By far the most important provitamin A carotenoid is beta-carotene; other provitamin A carotenoids are alpha-carotene and beta-cryptoxanthin.reformed vitamin A is found in foods from animal sources, including dairy products, fish, and meat (especially liver). By far the most important provitamin A carotenoid is beta-carotene; other provitamin A carotenoids are alpha-carotene and beta-cryptoxanthin.