Dog Dander

Transmitted Off Crossed Polarized Light Illumination

Dog skin flakes tend to be about three times or more as long as they are wide. In indoor
tapelift samples they can be confussed with very fine wood sawdust particles but the wood
sawdust particles almost always contain cell structure of distictive fibril structure at
the edges that distinguish the sawdust from the dog dander. Sawdust has a much higher
birefringence than dog dander and so can easily be distinguished when viewed with crossed
polarized light. The stress birefringence evident in the dog dander is typically irregular
in terms of its expression within the particle and from particle to particle.