A pediatric nutritionist is a registered dietitian (R.D.) that has specialized in nutrition for children, so you must first become a registered dietitian. You could enroll in a bachelor's degree program accredited by the Commission on Accreditation for Dietetics Education.
Here is part 1 of Cockatiel Types and Descriptions which covers 5 types of cockatiel types including whiteface, lutino, albino, normal greys, and pied. Each ... Here is part 1 of Cockatiel Types and Descriptions which covers 5 types of cockatiel types including whiteface, lutino, albino, normal greys, and pied. Each slide gives a bried description of what each type looks like, and includes a photo. Please watch part 2 for more types. Thanks for watching. :) I own none of the photos shown in the following video.
Cinnamon: The Cinnamon cockatiel is a mutation which causes the feathers which are normally grey to appear brown. The plumage color can range from a tannish-grey to a chocolate brown. Cinnamon-Pearl: A double mutation with the coloration of a Cinnamon and the feather pattern of Pearl. The female Cinnamon-Pearl often matures with a yellow face. The male will lose most or all of his pearling by the second molt.