Veterinarians



Dr. Jack Sinnigen

Dr. Jack Sinnigen

Co-Owner, Veterinarian

Growing up in Providence, Rhode Island, Dr. Sinnigen remembers returning bottles to the market down the street, using the cash he received to buy cans of cat food for the strays around the neighborhood. When it was time to apply for college, Jack had long ago decided to become a veterinarian!

Dr. Sinnigen attended the University of Pennsylvania to receive his Bachelor's in Biology. He met his wife, Betsy, in veterinary school with whom he now co-owns Sudbury Animal Hospital! The fall after graduating, Jack was accepted to the University of Pennsylvania's Veterinary School, graduating in 1984. He took a job at a small practice outside of Philadelphia while he waited for his wife to graduate-when she did, they worked at separate hospitals for a while before finding and purchasing Sudbury Animal Hospital.

Jack's professional interests include dermatology, ear disease, endocrinology, client education, and surgery. One of his most important practice philosophies is to give clients several options, so knowing a wide variety of techniques is very important to him.

Dr. Sinnigen and his wife have three children: Christine, who works at the New England Aquarium and also coaches lacrosse; John, who works for a consulting firm in Chicago; and Kyle, who attends the University of Maryland and is interested in becoming a veterinarian like his parents! At home, Jack and his wife have three pets-Batty is a cat adopted from Maine, Tori was found alone in the woods and given to the Sinnigens, and Lucas is a Labrador retriever.

In his free time, Dr. Sinnigen loves fishing, boating, golfing, being outdoors, and spending time with family and friends.




Dr. Betsy Allen Sinnigen

Dr. Betsy Allen Sinnigen "Dr. Allen"

Co-Owner, Veterinarian

Betsy's reasoning for becoming a veterinarian is simple-she loves animals, and she loves solving puzzles. What better way to combine the two than with a career in veterinary medicine!

Dr. Allen-Betsy's name around the clinic to avoid confusion with her co-owner husband, Dr. Jack Sinnigen-grew up in Westfield, New Jersey as the youngest of three daughters. She completed her undergraduate studies at Brown University, volunteering at a small animal practice in Eastham in the summers. She went to veterinary school at the University of Pennsylvania's School of Veterinary Medicine, where she met her future husband. On December 1, 1987, they purchased Sudbury Animal Hospital, which they've since built into a fully-staffed, state-of-the-art veterinary clinic.

As a veterinarian, Dr. Allen enjoys general medicine practice and surgery. To be considered a pet owner's “other family doctor” is a true thrill for her! She also likes caring for geriatric patients and educating clients on their older pets.

Betsy's family consists of her and Jack's three children, a dog named Lucas, and two cats, Batty and Tori. Outside of work, Dr. Allen enjoys reading a good book, walking her dog on the conservation land in town, and being out on the water with her husband. She's also been working on her golf game, although she says she'll never be a good golfer!




Dr. Donna Tizard

Dr. Donna Tizard

Associate Veterinarian

From a young age, Dr. Tizard had a strong interest in biology and chemistry. She was always fascinated by the human-animal bond, especially involving horses. It was these interests and inspirations that drove her to pursue a career in the field of her true passion: veterinary medicine!

Dr. Tizard grew up in a small town in northern Vermont. She attended the University of Vermont to receive a Bachelor's degree in Biochemistry. After graduation, she worked in cancer research at Tufts Medical School before working for biotechnology corporation Biogen for five years. She knew she didn't want to work in research forever, so she decided to pursue her lifelong passion of animal care. It was then that she applied to veterinary school, a decision that Dr. Tizard considers the best she's ever made!

Dr. Tizard lives with her husband, their daughter who is currently attending college, and their son, who is a senior in high school. The family has two Ragdoll cats, Morrissey and Rocky, as well as an Oldenburg dressage horse named Don Diego who likes to steal his pasture-mates' hay!

In her spare time, Dr. Tizard enjoys riding and taking care of her horse, skiing, tennis, biking, and knitting.




Dr. Joanna Alexander

Dr. Joanna Alexander

Associate Veterinarian

Jody always loved working with animals, and she also enjoyed the diagnostic and scientific challenges of medicine. A career in veterinary medicine was the perfect way to combine her interests and passions in a fulfilling way!

Born in Winchester, Massachusetts, Dr. Alexander originally attended college for research and Latin studies. While getting her doctorate, she gradually realized that she'd rather be a veterinarian! She completed her Master's degree, then took pre-vet courses before heading to vet school at Tufts University. She was attracted to Sudbury Animal Hospital's approach to veterinary medicine, and joined the team in 2008.

Dr. Alexander is married to her wonderful husband Kyle. Together, they have three amazing sons: Ethan, Tyler, and Drew. The family's pets include Rufus, a Golden Doodle with a talent for counter-surfing, Harry, a diabetic cat, and Louie, an orange cat who likes to hang out in the shower with Jody! Dr. Alexander's son also has a guinea pig named Pepsi who likes to call out asking for green veggies.

Outside of work, Joanna spends a lot of time attending her boys' soccer, basketball, and baseball games. She's also an avid bike rider, having biked around France, Spain, and most of New England with her husband.




Dr. Jennifer Probert

Dr. Jennifer Probert

Associate Veterinarian

Growing up in upstate New York, Dr. Probert was always surrounded by pets. She had a German shepherd named Katie and a sheltie named Mindy Mittens, and she also had plenty of fish and hamsters throughout her elementary school years. As she grew older, she became passionate about promoting and developing the human-animal bond, so she decided to become a full-time veterinarian!

Jen attended Quinnipiac University to receive her Bachelor's in Veterinary Technology, working as a Research Assistant at Yale University afterwards. She then moved to Colorado, earning a second Bachelor's degree in Equine Science. From there, she was accepted to the Western University of Health Sciences in California to receive her veterinary degree. She came to Sudbury Animal Hospital in January of 2012, after leaving her previous position at a large corporate practice.

Dr. Probert's professional interests include surgery, dentistry, and canine rehabilitation. She is a certified canine rehabilitation therapist and takes pride in helping pets to recover from injury and orthopedic surgery.

At home, Jen has three pets of her own: Bee Gee, a Chihuahua/terrier mix, Roxy, a German shepherd puppy, and Scarlett, a cat who was Jen's first spay in veterinary school. Dr. Probert enjoys snowboarding in her spare time, as well as cooking, photography, and taking her dogs out for hikes when the weather is nice.




Dr. Josh Gidlewski

Visiting Ultrasound Specialist

Dr. Gidlewski attended Pennsylvania State University for his undergraduate degree and earned his Doctor of Veterinary Medicine degree from the University of Georgia in 2000. After completing an internship at the University of Illinois and a three-year residency in Cardiology at the Animal Medical Center in New York, Josh became Board Certified in Cardiology in 2004. From 2004 to 2007, Dr. Gidlewski headed up the cardiology department at the Garden State Veterinary Specialists in Tinton Falls, New Jersey, and then brought his skills to the area when he joined the New England Veterinary Specialists.




Dr. Andy Abbo

Visiting Ultrasound Specialist

Dr. Abbo attended Colorado State University for his undergraduate degree and earned his Dr. of Veterinary Medicine degree from Kansas State University in 2004. After completing a rotating medicine and surgical internship at Purdue University, he remained at Purdue and completed a three- year comparative oncology residency becoming Board Certified in Oncology in 2009. Andy has practiced in the metro Boston area, Cape Cod and South Shore for the past 7 years, he joined the New England Veterinary Specialists in 2015.




Dr. Robert McCarthy

Visiting Surgeon

Dr. McCarthy is a board certified veterinary surgeon who specializes in both orthopedics and soft tissue surgery. He will visit the Sudbury Animal Hospital and bring his expertise to specialized surgeries and orthopedic consultations. When he is not visiting area practices, he is on the faculty at the Tufts University Cummings School of Veterinary Medicine, as a surgeon.

Dr McCarthy graduated from Tufts University School of Veterinary Medicine, in their inaugural class of 1983. He served on the faculty of Louisiana State University and the earned his masters degree at the University of Minnesota in 1992. He returned to Tufts as a faculty member in 1993 and started his traveling surgical practice shortly thereafter.