There are things you could do with that degree in the government without being a veterinarian - analyst type work, for example.
At one of my internships was doing policy work with the Food Safety Inspection Service. There were a couple of DVMs in the department, but most of the people there were either lawyers, had something like a master's in public policy, or had worked their way up from non-vet field positions. My boss had a MA in philology though, so it's not like any of those degrees were strict requirements. A MPH, especially a veterinary focused one, certainly would have qualified you to work there. I've also known several people who did import / export related analysis work for APHIS that were not DVMs (don't remember what their degrees were in). I'm sure there are other departments where you could find positions too.
I'd have to think about how to search for those types of jobs, but honestly searching "analyst" or "staff officer" or "advisor" on usajobs and restricting your search to agencies that have vet med jobs might give you a start (usda, noaa, fish and wildlife service, military branches, bureau of land management, smithsonian, probably others that I'm forgetting). You can also try different search combos to try to find other generic jobs titles that are common to the field. If you see similar terms popping up in relevant jobs, you can refine your searches to be more targeted to positions you would be qualified for. (Maybe "veterinary," "animal," or "public health", etc).
You'd be overqualified for an animal health tech position with the federal government, but you would meet the requirements if you had enough clinical experience in vet med as an assistant or a tech. You would not need to be licensed - federal government employees are exempt from state licensing requirements. (The hiring official may prefer it though.)
You could also find work with corporations. There are probably positions with large agricultural producers (think Tysons or Smithfield, for example) that you would be qualified for. Infection prevention/control, HACCP planning, etc are all areas where I could see there being jobs for an MPH grad. Veterinary pharmaceutical companies would also be a good place to consider looking.
Also at the end of the day an MPH is an MPH, vet med concentrated or not. As long as the program is accredited, you'll have to learn core principles that apply broadly to public health. You can always find work in a public health department, hospital, or similar with that degree, it just may be focused on human health concerns.
Sorry this is a bit of a brain storm... If you have questions or specific areas you would want to work in, I can try to better focus my thoughts on potential jobs.
