If you’re looking for cutting edge veterinary medicine with compassionate staff, visit the Mansfield Animal Clinic!

At Mansfield Animal Clinic, our mission is to treat you and your pet with the utmost respect and love. We will treat both you and your pet the same way we would want to be treated ourselves, taking into consideration your needs and wishes. We will strive to educate you about your pet’s condition so that you can make informed decisions. Recognizing that new information and techniques are becoming available at a very rapid pace, we will through continuing education regularly upgrade and improve our skills.


Mack T McClister, DVM – Medical Director

Dr. McClister was born in Tupelo, Mississippi and raised in San Antonio, Texas. He graduated from Texas A&M College of Veterinary Medicine in 1970. He became a partner at Mansfield Animal Clinic in 1971. Dr. McClister was a mixed animal practitioner until 1990, when he limited his practice to small animals only. He is active in the Shepherd’s Valley Cowboy Church, a member of the Johnson County Sheriff’s Posse, and an active team roper. Dr. McClister is married with 2 children, 2 step-children and 8 grandchildren.

  • Years in Practice: 44
  • Education:Texas A&M

Jason Ferrell, DVM

Dr. Ferrell graduated from Texas A&M College of Veterinary Medicine in 2011. Dr. Ferrell has practiced in Chicago, IL and other parts of northeast Texas before coming to Mansfield Animal Clinic.

Dr. Ferrell has strong interests and a background in emergency medicine, general practice medicine, and soft tissue surgery. Dr. Ferrell’s family includes his wife, 3 daughters, and a goofy housecat.

Kara Lewton, DVM

Vet School / Grad Date:
Texas A&M Class of 2015, Bachelor’s in Biochemistry with a minor in German from Baylor University Class of 2009

Why you became a vet?
I have had a lifelong love of animals and there was never any question in my mind that I wanted to spend my life helping them. I originally planned on being an equine veterinarian, but quickly discovered a deep passion for feline medicine once I started veterinary school and decided that small animal medicine is definitely where I belong.

A lynx point Siamese cat named Meow Ming (like Yao Ming, the former Houston basketball player), but his nickname is Mingles, and a red eared slider turtle named Donatello.

I have 2 older brothers, Chris, who works for PepsiCo in Frisco as a computer programmer, and Aaron, who is a pilot in the Air Force flying C-5s, which are the planes large enough to transport armored tanks, and also flies for Delta. My mother lives in Houston and works at a Catholic church as a director of faith formation.

Interests outside of work?
My biggest interest and passion is music. I have never been very good at playing any instruments because I was very focused on becoming a veterinarian, so I ended up getting involved in the concert scene supporting musicians instead. When I was at Baylor I even volunteered for several music labels to promote bands, some of which have become rather famous now, such as Panic! At the Disco and Twenty One Pilots. My absolute favorite band is The Academy Is… who unfortunately broke up in 2011, but I still keep up with the individual members of the band and have become close friends with the lead singer, who has a solo career now. I try to go to at least one concert a week, even if it is just a small show at a tiny club with less than 50 people. I also enjoy reading, hiking, traveling as much as I can, and horseback riding (though I haven’t been on a horse in several years).

Cool things people should know about you?
Definitely a Ravenclaw, as Sam said, lol! I am a giant nerd when it comes to Harry Potter and a lot of other sci-fi/fantasy fandoms. I am also planning on completing an ABVP specialty in feline medicine once I have 5 years of experience as a practicing veterinarian.

Contact Us Today!

Contact Us Today!

Contact Us Today!

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