Meet the Veterinarians & Staff of ZimmVet


Maria R. Krenz, DVM, Owner

Maria R. Krenz, DVM, Owner

Dr. Krenz has been practicing veterinary medicine in the Zimmerman area since 2007. She purchased ZimmVet in December 2008 after longtime owner and founder, Dr. Tony Damer, retired. She is passionate about providing the highest standard of care to companion pets in the form of new technology and updates to the clinic to better serve pets and clients.

Dr. Krenz holds a Doctorate of Veterinary Medicine from the University of Wisconsin-Madison and a bachelor of science degree in animal science from the University of Wisconsin-River Falls. She also regularly attends national and regional seminars, conferences, and workshops in order to stay up-to-date on the latest protocols and veterinary medical techniques.

Dr. Krenz lives on a hobby farm outside of Princeton with her husband, Josh and daughter where they raise horses, cats, chickens, sheep, and cattle. In her spare time, she enjoys gardening and working on their farm and house.

Hillary McCulloh, DVM

Hillary McCulloh, DVM

Dr. McCulloh is a native of St. Cloud, Minn., and grew up on hobby farm where her family raised sheep and horses. Being a veterinarian was a lifelong dream, and a goal that began at the young age of 3. Dr. McCulloh graduated from the University of Minnesota College of Veterinary Medicine in 2006. After graduation, she traveled across the country and worked at several veterinary clinics, where she provided care for a number of different species in addition to dogs and cats. Dr. McCulloh also spent some time in the Western part of the United States, working for an animal shelter. She continues to be involved with various shelters and rescues presently.

Dr. McCulloh enjoys the diverse challenge of all aspects of general practice, but has a special interest in surgery with an emphasis on dentistry. Dr. McCulloh is constantly working to stay up-to-date on the latest veterinary medical information, and she frequently attends local and national continuing education workshops on various veterinary topics. Her favorite continuing education involves learning more about dentistry, especially hands-on dentistry wet labs where she practices the latest techniques and masters her dentistry skills.

When not at work, Dr. McCulloh continues to help her family with their sheep hobby farm. She also enjoys spending time outdoors hiking with her dogs, biking, cross country skiing, and riding her horses.

Stacy York, DVM

Stacy York, DVM

Dr. York holds a Doctorate of Veterinary Medicine from the University of Minnesota. After graduation, Dr. York has practiced small animal veterinary medicine in the Twin Cities area. Prior to becoming a veterinarian, Dr. York spent time learning about veterinary medicine by working as a kennel attendant, receptionist, technician assistant and veterinary technician. Dr. York enjoys being a general practitioner, and she has a very strong interest in surgical procedures.

Continuous education and learning is important to Dr. York and her ability to serve the individual needs of each patient. She accomplishes this by being an active member of the Minnesota Veterinary Medical Association, the American Veterinary Medical Association, the American Animal Hospital Association, and the Minnesota Veterinary Response team. In the past, she has also been a veterinary volunteer for RAGOM. She has also served as a foster home for Human Society's Orphaned kitten project. Dr. York is also a former member and foster parent for Second Chance St. Bernard Rescue and past member of Northstar Newfoundland Club.

Having been born and raised on a small beef cattle farm in Iowa, Dr. York enjoyed the opportunities to work with a wide range of animals growing up. Today, Dr. York lives in the Twin Cities with her husband, Mike and their two children. She also has two domestic long-haired cats, and three dogs (Chewy - Newfoundland, Dozer - English bulldog, and Lulu Belle - French bulldog). In her spare time, Dr. York aspires to enjoy photography, scrap booking, hiking, biking, boating, cooking, reading, and working on home improvement projects with her husband.

Technician Staff

Kristin Rinkel, CVT

Kristin Rinkel, CVT

With over 11 years of experience, Kristin chose to be a professional veterinary technician because of her compassion for helping pet owners understand the health needs of their loved ones. This compassion can be seen in how she approaches every individual pet.

Kristin began her career by fulfilling a variety of veterinary clinic roles, including working as a veterinary assistant, receptionist and kennel worker. In 2009, Kristin graduated from the Minnesota School of Business with an Associates of Science Degree in Veterinary Technology. Today, Kristin is a Certified Veterinary Technician.

Having a father in the U.S. Army, Kristin was born in Germany and spent many of her younger years overseas and in other parts of the U.S. She spent the remaining parts of her childhood and young adult life in Minnesota. Kristin currently lives in Princeton with her husband Jake, and their infant daughter, Autumn, as well as her furry friend Pumpkin (cat).

Ashley Middendorf, CVT

Ashley Middendorf, CVT

Growing up as a child, Ashley's passion for veterinary medicine was greatly influenced by close family and friends with careers in the veterinary field. She would spend the summers while growing up in Wisconsin at her Aunt's veterinary clinic, which allowed her to observe the veterinary field in action. These experiences encouraged her to pursue a career in veterinary medicine.

After high school, Ashley pursued her passion for animals by attending the University of Minnesota for animal science. During this time, she decided to pursue the veterinary technician career path. She transferred to Minnesota School of Business and graduated with her Associates of Science Degree in Veterinary Technology in 2010. As a Certified Veterinary Technician, one of her first jobs was as a veterinary technician at a humane society. She enjoys continuing her education with conferences, and being an active member of Minnesota Association of Veterinary Technicians.

Ashley resides in Big Lake Township with her husband, Chris and daughter. They share their home with four dogs & 2 cats. Besides working as a Certified Veterinary Technician Ashley manages the Technician Internship program at ZimmVet.

Wanda Becker, CVT

Wanda Becker, CVT

After many years of taking her own pets to her local veterinarian, Wanda began exploring her own career in Veterinary Medicine by shadowing veterinary technicians at the veterinary clinic where she took her animals.  In 2002, Wanda earned an associate of applied sciences degree in veterinary technology from Argosy University.  She worked at the Monticello Pet Hospital for 11 years before joining the technician staff at ZimmVet. 

Wanda is a certified veterinary technician and enjoys advancing her knowledge of veterinary medicine by earning continuing education credits at conferences such as the Minnesota Association of Veterinary Technicians conference.  She is especially passionate about dental care, but Wanda also uses her enthusiasm for high quality veterinary care to assist patients in all of their medical needs.

A Minnesota native and life-long animal enthusiast, Wanda currently has one dog, a black lab named Lucy.  In the past, Wanda has also had Chesapeake Bay Retrievers and orange cats.  She has one grown son, who attends college and is a member of the Minnesota Army National Guard.

Rebecca Hell, CVT

Rebecca Hell, CVT

A native of Zimmerman, Minn., Rebecca started her career in the veterinary field in 2012 by working at ZimmVet as a Veterinary assistant.  During that time, she worked alongside our Veterinarians & Technicians, studying the skills of the ZimmVet staff and learning along the way. Rebecca graduated Argosy University in 2015 with an Associate’s Degree and soon later became certified as a Veterinary Technician.

As a child, Rebecca always knew she wanted to become a Veterinary Technician.  Through hard work, dedication and a lot of time spent with pets, she is happy to be living her childhood dream. When not mastering her Veterinary Technician skills, Rebecca volunteers as a foster home for a local dog Rescue.  She also loves spending time with her own, very spoiled dog, Bambi.  Rebecca looks forward to growing in her career as a Veterinary Technician by continuing to help ZimmVet clients.

Support Staff

Amy Johnson, CVT, Lead Customer Service Representative and Pet Hotel Reservation Manager

Amy Johnson, CVT, Lead Customer Service Representative and Pet Hotel Reservation Manager

Amy started her career in veterinary medicine in 1993, and now serves as the lead receptionist for ZimmVet. She holds an Associate of Science Degree from the Medical Institute of MN, Veterinary Technology Program. Amy enjoys veterinary medicine because it is an ever-changing and challenging profession. Her career choice also fuels her passion for animals by providing pets with a positive medical experience every day.

A certified veterinary technician, Amy uses her 20 years of experience to help customers understand the services offered by the clinic. This firsthand veterinary technician experience gives her an in-depth perspective when discussing services performed on our client's pets.

Amy resides in Milaca, Minn., with her husband and their many animals. She enjoys spending time with her many varied animals and working on outdoor projects.

Amy spends her time taking care of customer's needs at the reception desk, managing the reception staff and keeping the clinic book keeping up to date. Amy also manages all of the reservations for the Pet Hotel.

Stephanie Mistretta-Murschel

Stephanie Mistretta-Murschel

Stephanie has been an avid animal lover her entire life. She grew up with many canines around her house, including Alaskan Malumutes, American Eskimos and Golden Retrievers. In addition, she expressed her love for dogs by volunteering for a local Golden Retriever rescue for ten years, during her youth.

With more than 10 years of customer service support, Stephanie works with customers to listen to their needs and to help them in each unique situation. Her pet care career began in 2007 and includes past experiences at a boarding and grooming facility as well as a 24-hour animal hospital. Combining her customer service experience and pet care experience, helps Stephanie provide personalized pet care to every patient.

A St. Louis, Mo., native, Stephanie now resides in Foreston, Minn., with her husband Randy and their two cats (Mila and Lola) as well as their Golden Retriever (Seger). In her spare time, she plays softball and enjoys attending St. Louis Cardinals and St. Louis Blues games as well as traveling to NASCAR races.

Pet Hotel, Dog Daycare and Technician Assistant Staff

Kari Buse, Dog Daycare Manager

Kari Buse, Dog Daycare Manager

Kari's love of animals started at a very young age growing up on a horse farm in southern Minnesota. After graduation from High School Kari earned her Bachelor of Science degree in Equine Science from the University of Minnesota. Kari then went on to  train horses professionally and give horsemanship lessons. Kari also holds a certification in Equine Sports Massage.

Kari uses her extensive knowlege of animal behavior and background in horse training when working with the daycare dogs. Kari enjoys getting to know each individual dog and their needs.

Kari lives with her husband, Danny and their dog Bella in Isanti. She enjoys spending time on the lake, hunting, fishing, horseback riding, reading and riding motorcycles. Kari is also active with the local 4-H groups and volunteers to help other young horse enthusiasts.

Elena Cain

Elena Cain

Client Testimonials

Last Saturday was our first time there and our experience was a 5! Everyone was very informative and welcoming! Thank you!

— Carole Lefebvre

Bringing both of our dogs to be cared for, we are extremely pleased with the care they are receiving. Sadie, Willow and I thank you all.

— Sue Lenz

I really appreciated the way the doctors at the clinic cared for Diamond. Over fifteen years of love with my wonderful dog and the quality of regular care she received at the clinic made it possible. I was especially touched by the sympathy card I receive after sadly having to put her to sleep, it shows they really care.

— Darryl Anton

After recently moving to Minnesota we researched many veterinarian options and we chose the Zimmerman Veterinary Clinic. The staff was honest, thorough and genuinely caring. Their follow-up on our pets care was outstanding. Itís worth the trip for your petís care.

— The Connorsí Family - Rich & Amy Maximus, Petie, Buster, Bandit, Shadow, Kodibear & Sammy

We have taken our pets to the Zimmerman Vet Clinic for 20 years. Even when our visit was a sad one, we were treated with kindness and courtesy. The staff has always been professional and friendly. We highly recommend Zimmerman Vet Clinic to anyone who loves their pet.

— Bratsch

The staff at Zimmerman Veterinary Clinic has taken care of my dogs since 1979. I am especially pleased with the care of my last companion/friend, Ruby Mae. She received the best care I could have expected. The staff gave her loving care and attention during her whole lifetime. I canít thank them enough for being there for support. I will continue to use them with my new friend, Baily Sue.

— Sincerely, Dale Cannon

We love Zimmerman Vet! They give the best care & have a wonderful staff!

— Laurie Gansen Cramer

Thank you all for being such amazing people & taking such great care of my little man Bentlee! You will never know how much I appreciate all your information, fast actions & the care you put forth to all animals that come to your office! Thanks Again!

— Dani George

Iíve had dogs all my life and this is by far the best place to take your pet for their veterinary needs!!! Great service from the entire staff, they really care about the wellness of your pet, and my Gauge gets a little extra TLC (he is a senior now).

— Bonni Placek Cook