The following books are recommended for all behavior consultants regardless of which species worked with. While some books have "dog" in the title, the material covered is excellent and applies to all species.

Physiology of Behavior by Neil Carlson,

Don't Shoot the Dog: The New Art of Teaching and Training by Karen Pryor

Veterinary Psychopharmacology by Sharon Crowell-Davis

Animal Behavior: an evolutionary approach - 8th edition by John Alcock

How Dogs Learn by Mary Burch and Jon Bailey

Measuring Behaviour: An Introductory Guide by Martin and Bateson