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.
â The vitamin A from animal sources is retinoids, also called retinol, while plant source vitamin A is carotenoids, such as beta carotene. Animal sources of retinol is bio-available, which means the body can utilize it.he most important fact about vitamin A is the difference between retinoids and cartenoids. The vitamin A from animal sources is retinoids, also called retinol, while plant source vitamin A is carotenoids, such as beta carotene. Animal sources of retinol is bio-available, which means the body can utilize it.