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.
If you are getting cockatiels for breeding, they should be 18 months old, even though they are capable of breeding as young as 5-6 months of age. Younger females can have physical complications, like egg binding.