Meet the Vets 

We are extremely fortunate to have three very talented veterinarians staffing our clinic and overseeing the care of the animals in the APA shelter. As the many pet-owners who are long-time clients here will tell you, they are also incredibly thoughtful and caring with the human as well as four-legged visitors they see each day.

Denise Dietsch, DVM
Director of Veterinary Services

Dr. Denise Dietsch DVMI'm a grad of the University of Missouri Veterinary College (Class of ’76) and a native St. Louisan who’s proud to have grown up on the South Side.

My first experience out of vet school was working in a private practice owned by one of the St. Louis Zoo veterinarians. Though I didn't work at the zoo, his expertise with “exotics” attracted an unusual variety of animal clients. While I treated mostly cats and dogs, my daily routine during those seven years often included mountain lions, monkeys, birds and reptiles.

From there, I was on staff at another local private veterinary hospital. About 8 years ago I joined the staff of the APA. Here I am in charge of our outpatient clinic that is open to the public. I also oversee the healthcare of the dogs and cats that are housed in our shelter.

Outside the APA, I'm the mother of one lovely daughter, Alexandra, and 3 dogs and 2 cats. My free time is spent on remodeling and decorating my house or crafting miniatures. (Ask me about the guitars I’ve built!)


Shannon L. McCollough, DVM

I graduated from Colorado State University Veterinary School in 1990.  After completing a one-year internship at the Sacramento Animal Medical Group in northern California, I began my career in Denver, CO at Alameda East Veterinary Hospital (of the Animal Planet Channel's "Emergency Vets" fame!).  My husband's job transferred us to Tulsa, OK for two years, and then brought us to St. Louis in 1995. 

After working in general small animal practice in West County for almost 13 years, I left the private sector in September of 2008, to work on a short-term project for St. Louis County helping to implement a Reduced Fee Spay/Neuter program.  Once I had a taste of working in animal welfare, working part-time for the APA is exactly where I want to be after almost 20 years in veterinary medicine!

I am president of the Greater St. Louis Veterinary Medical Association and a member of the Animal Welfare Committee for the Missouri Veterinary Medical Association.  When not immersed in Veterinary Medicine and Animal Welfare, I spend time with my husband, Mark (a partner in a road construction company) and our 8 year old son, Luke.  We have 3 pets: McLaren - a Golden Retriever, Tucker - a Maine Coon, and Murcielago - a DSH. (Note: All 3 pets are named for a McCollough family passion: CARS!)


William Bogash, DVM

 I grew up in South St. Louis, but after vet school (University of Missouri) I moved
to Franklin county and began my own veterinary practice.  Later, I sold that clinic so I could specialize in surgery.  I have always enjoyed working with shelter and rescue animals.   

I have been doing spay/neuter surgeries at the APA for 10 years, and I now help in the
clinic on Saturdays.  My hobbies are fishing, swimming, canoeing, hiking and gardening - I love being outdoors!  I share my home with two German Shepards and two cats.