About Ellie Diagnostics

Putting wellness at the forefront of animal health

Ellie Diagnostics is a full-service veterinary wellness and diagnostics laboratory dedicated to transforming animal health by making wellness testing more accessible.

At Ellie, we believe wellness bloodwork is essential, and should be standard and attainable for every pet, every year.  With Ellie, veterinarians can enjoy great quality and prices with no contracts, minimums or unexpected price increases. 

The result? Healthier pets, and healthier profits.

Our Commitment

A better wellness experience.

Plus, all the perks of our full-service diagnostics:

Our Leadership

Experienced management team

Mark Decourcy

Founder & CEO

Mark DeCourcy is the founder and CEO of Ellie Diagnostics. Mark has deep experience in healthcare diagnostics but was inspired to shift into animal health by his dog, Ellie, after a bad experience with diagnostics at the vet consisting of a high price tag and nothing to show for it. He has assembled a team of animal health experts to develop a suite of innovative services to improve that experience and to help animals live longer, healthier lives.

Prior to founding Ellie, Mark served as Vice President of Strategy at True Health Diagnostics where he played a critical role in driving strategic growth and oversaw mergers & acquisitions.

Mark holds an MBA and Masters of Science in Finance from The University of Texas at Dallas, and a BS from Texas Tech University with majors in Finance and Economics.


Chief Dog

Ellie is a 12 year old Cavachon who oversees general operations with a focus on treat distributions. She has 12 years of experience being alive and graduated with honors from having Mark take her on longer walks than necessary in 2015.

Medical Advisory Board

ANIMAL healthcare and veterinary Experts

Dr. Kent Julius


Dr. Julius is the Founder of Legacy Veterinary Hospital. He received his Doctor of Veterinary Medicine degree from the University of Illinois in 1999. During veterinary school he worked as a research assistant grant program that involved trapping and releasing wildlife near swine farms to determine the spread of viruses. He also served as a research assistant in the U of I Toxicology Lab for three years. After graduation he worked for the largest veterinary hospital in Carrollton. He then joined a three-doctor small animal hospital in Coppell for two years before opening Legacy Veterinary Hospital. He also served as a relief veterinarian at the Fort Worth Zoo for 3 years.

Dr. Derrick Nelson


Dr. Nelson earned a bachelors degree in Animal Science in 1998 and a doctorate degree in Veterinary Medicine in 2002; both from Texas A&M University. During Dr. Nelson’s fourth year of veterinary school, he completed an externship in Kentucky working multi-million dollar thoroughbreds, including Kentucky Derby winners.

Since graduating from veterinary school, Dr. Nelson has worked in various veterinary clinics in the DFW area. In April 2011, he bought Town and Country Veterinary Clinic from his friend and colleague, Dr. J. Mac Todd.


Ellie offers an entrepreneurial environment where our employees are our top priority. We are constantly looking to add to our team.