Animal Dander All warm-blooded animals shed tiny flakes from their skin called dander. (It's like dandruff in humans but much harder to see.) It's this dander - along with proteins from saliva and other fluids that may be on an animal's skin - that causes allergies in humans. Back to Articles Related Articles Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.