Director of Small Animal Clinical Services UC Davis, Professor Dr Sykes received a diploma of veterinary doctor and defended her doctorate at the Univesity of Melbourne in the field of veterinary microbiology. She focused on the infections of the upper respiratory tract of cats. Then she completed a residency at the University of Minnesota and received a diploma in Small Animal Internal Medicine in the field of infectious diseases, the immune system and hematologic diseases. She is a co-founder and former president of the International Society Companion Animal Infectious Diseases and president ACVIM.
Her scientific interests include infectious diseases of dogs and cats, especially immunosuppressed animals, as well as fungal diseases and ticks. She is the author of numerous publications and co-author of many books including recently released Canine and Feline Infectious Diseases.