1. Beta-carotene that is not converted into vit A serves a protective barrier against disease. 3. VITAMIN A DEFICIENCY Vitamin A utilized in the body is dependent on 1. Quantity stored in liver a. Deficiency symptoms appear in 1-2 years due to high amounts stored in liver 2.
Wild Lifespan. In their natural wild habitats, cockatiels, on average, live between 10 and 14 years, indicates Animal Diversity Web via the University of Michigan. Their average age for passing away is younger in the wild than it is in captivity. Captive Lifespan Cockatiels that are kept as pets -- or that live in other captive settings -- can stay alive for up to 25 years or so.
Small parrots - Budgies live from 17-18 years. A finches average lifespan is 5-10 yrs, while a canaries is 10-15. Cockatiels can live from 15-20, Lovebirds 10-15, and Parrotlets 10-15. Medium parrots - Conures live from 12-30 yrs, Caiques up to 30, and Lories/Lorikeets 13-25. Large parrots - African Greys live from 50-60+ yrs, Amazons 50-70+, Cockatoos 40-60+, Eclectus' 65-85, and Macaws 50-100+. These are just average estimates for parrot lifespans and won't always be accurate.