Veterinarians play significant role in medical field, especially in drug discovery and basic science research. There is a specialized field called laboratory animal veterinarian whose primary responsibilities are care and welfare of animals that are used in research.
In response to your math interest, there are multiple areas you could use your math skills with veterinary medicine background. For example - epidemiology, public health, pharmacokinetics etc. That being said, mathematics is a integral part of every science field. Good luck with your studies.