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.
Suitable feeds for cockatiels are seeds such as millet, canary seeds, nyjer seeds, wheat, kardi seeds or oats. Seeds containing fats such as sunflower seeds and nuts should only be given to the birds in moderation. Foxtail millet is a special tasty titbit. Seed mixtures are also available to buy.