Catherine Werners-Butler, PhD, DVM, MRCVS, Dipl. ECEIM, Dipl. RNVA

Associate Professor
Diplomate European College Equine Internal Medicine
Large Animal Medicine and Surgery Academic Program

Dr. Werners-Butler graduated with a degree in Veterinary Medicine from the University of Gent in 1998, followed by a Residency in Equine Internal Medicine with the Faculty of Veterinary Medicine at Utrecht University from 2001-2006. She is a specialist in Equine Internal Medicine with both the Royal Netherlands Veterinary Association and the European College of Equine Internal Medicine.

Her research has focused on the prevalence, incidence, persistence and significance of tick-related diseases in horses. Different laboratory techniques have been used (ELISA, IFAT, PRC-RLB, qPCR, cytology, in vitro culture and experimental infection) and compared. She has investigated the prevalence and incidence of Anaplasma phagocytophilumBorrelia burgdorferiBabesia caballi and Theileria equi in horses in the Netherlands. By doing so she has confirmed the first autochthonous clinical cases of Anaplasmosis and Babesiosis in Dutch horses. She has also evaluated the clinical relevance of B. burgdorferi infection in horses in a prospective study, given continuing controversy around this subject in horses, humans and other mammals. Furthermore, Dr. Werners-Butler has assessed the treatment efficacy against equine piroplasmata with imidocarb dipropionate, showing for the first time that Babesia caballi is not always eliminated in natural infected asymptomatic carrier horses. Using PCR-RLB in these carrier horses a potential new Theileria variant (provisionally named Theileria sp. Morito) was detected that seems to be more resistant to imidocarb treatment compared to Theileria equi. Experimental infection of T. equi and B. caballi in two ponies showed that, after complete clinical recovery, DNA from both pathogens is detectable in almost all organs at postmortem examination in different quantities, suggesting a tropism for, and persistence in specific organs.