Our Animal Doctor

meet our veterinarians

Natasha Ungerer, DVM –  Dr. Ungerer is a native of western New York. Growing up she always knew she wanted to be a veterinarian. Now, nearly ten years later she still thinks it's the best job. Dr. Ungerer obtained her BS degree from Sweet Briar College in southwest Virginia and her DVM degree from North Carolina University College of Veterinary Medicine. She then completed a one-year internship at a large referral/emergency hospital in Gaithersburg, MD. She has since worked in Richmond, VA and Frederick, MD before settling in Northern Virginia. Her professional interests include internal medicine, pain management and wellness and preventive care.

Dr. Ungerer and her amazing husband have two adorable daughters, as well as their two crazy dogs: Dewey - and English Pointer and Kirby - a hound mix. In her spare time she enjoys hiking, biking, skiing and occasionally cooking.


Kayleen Gloor, DVM, MS - Dr. Gloor is a true local. She grew up in Springfield, VA nd worked as kennel help/veterinary assistant at her neighborhood veterinary clinic while in high school. She graduated high school a bit young, so stayed close to home and attended NVCC while working in customer service for her father's furniture company. It was there she learned about the value of good client communication and service as well as got some great insight into small business ownership. She transferred to Virginia Tech for her undergraduate studies and stayed there for veterinary school. Upon obtaining her DVM in 2006 she came back to the DC area for a surgical/medical rotating internship at a large emergency/referral hospital in Gaithersburg, MD. It was there she met and befriended Dr. Ungerer. She has practiced in both general practice and emergency hospital settings in the DC area since 2006. Additionally, in 2009 she went back to school for a Masters in Public Health Microbiology & Emerging Infectious Diseases (nerd) at GWU. She completed this degree in 2011 - something she did while continuing to practice as well as working in a research lab at GWU. Her professional interests include infectious diseases, pain management, soft tissue surgery, emergency medicine and internal medicine.

Dr. Gloor is married and has a very opinionated daughter, two cats and a big, goofy English Mastiff named Gozer (the Gozerian - aptly named after the god of destruction from Ghostbusters). In her spare time she enjoys travelling, hiking, yoga, snowboarding and spending time with her family.


Sarah Tew, DVM - joining CAC May, 2017 - Dr. Tew is a native of the Midwest with roots in Iowa and Missouri. She grew up with many family dogs and cats, and while working for her family veterinarian during college she was quickly set on her career choice. Dr. Tew earned a BS in Biology from Park University in Kansas City, and then went to the University of Missouri  (Go Tigers!!) where she graduated with her DVM degree in 2006. During her first year as a veterinarian, she completed an internship in equine ambulatory practice at The Ohio State University.  Although she loved it, continuing with equine practice was not in the cards so she turned to small animal medicine and hasn’t looked back.  Dr. Tew’s professional interests include preventive care, dentistry, feline medicine (especially senior kitties), pain management, and internal medicine. Beyond medicine, she loves building relationships with her clients and patients and educating clients how to best care for their furry family members.

Dr. Tew lives in Leesburg with her Pointer mix, Stewart, and her former tabby farm cat, Emmitt. In her spare time, you will most often find her in her kitchen or backyard garden, at yoga, reading in or near a body of water, and most importantly, spending as much time as possible with her two adorable nieces, family, and friends.


Clare Rathjens, DVM - Dr. Rathjens jointed CAC July, 2016! Dr. Rathjens grew up in Columbus, Ohio. She always loved animals as a child and decided to become a veterinarian after discovering a love of biology in college. Dr. Rathjens obtained her BA from Oberlin College and her DVM degree from the Ohio State University College of Veterinary Medicine in 2014. During her clinical year at Ohio State, Dr. Rathjens was the recipient of the Excellence in Community Practice Award. She practiced general medicine in Maryland before coming to Clarendon Animal Care in 2016. Her professional interests include dentistry, behavior, and internal medicine.

Dr. Rathjens lives in DC with her husband, daughter, and energetic beagle-pitbull mix, Reece. In her free time she enjoys walking, knitting, spending time with family, and traveling.


Brittani Nickens, DVM - joining CAC June, 2017 - Dr. Brittani J. Nickens was born and raised in Philadelphia, PA. As a young child, she was always outside playing with caterpillars, earth worms and rescuing injured birds; it was at age 5 when she decided her career choice to be a veterinarian. She attended Penn State University (State College) where she earned a B.S. degree in Animal BioScience and then went on to graduate Magna Cum Laude with her D.V.M. from Tuskegee University School of Veterinary Medicine in 2014. She then continued her training at Garden State Veterinary Specialists in New Jersey and completed a small animal medicine/surgery rotating internship. Dr. Nickens worked as a relief veterinarian in Philadelphia, PA for a few months before moving to Las Vegas to work general/emergency medicine. While in Vegas, and in the midst of working and caring for her four-legged children, Dr. Nickens met and married her wonderful and supportive husband. Her professional interests include: Ophthalmology, Soft Tissue Surgery and Dentistry. She really has a love for providing individualized and compassionate care for her patients and establishing relationships with her clients.

Dr. Nickens and her husband decided to move to Northern Virginia/D.C. area for better job opportunities and to be closer to family. They share a home with a Rottweiler/Doberman mix named Coco, a pitbull mix named Keno and a cat named Brie. In her free time, Dr. Nickens enjoys dining, shopping, traveling and spending time with loved ones. She also enjoys playing basketball, tennis and bike riding.


Darleen Nath, DVM, CVA - Dr. Nath has, unfortunately, moved to Houston, TX. Her last day with us was May 10, 2017 . We are terribly sad to lose her, but wish her and her growing family (she's due with baby #2 in July!) all the best. She will be doing relief work at the clinic featured in "The Vet Life" on Animal Planet - perhaps we can catch her on TV in the future!!