I have two large dogs, and I let them in the house a lot. When I began sampling the dust in my house, I found a lot of dog dander, which is tiny flakes of their skin. This picture shows two flakes and two dog hairs. Cats and other pet shed skin flakes, and we do, too.
Some people are allergic to different kinds of dander.
What they are really allergic to are oils and other chemicals on the skin and hair of these furry animals. This material may not be reproduced in any form without express written permission.