Our caring and compassionate veterinary care team!

Meet the Veterinarians & Team of Riverside Pet Hospital in Ajax! We’re pleased to provide exceptional vet care for your pets!

Please call us at 905-683-8080 to speak to one of our caring veterinary staff members!

Dr. Mike Korosi D.V.M.

Dr. Mike Korosi received his Doctor of Veterinary Medicine degree in 1991 from the Ontario Veterinary College at the University of Guelph.

After graduation, he practiced in Mississauga, where he met his future wife, Patti, a veterinary technician student at the time. They both dreamed of owning their own practice that celebrated the human-animal bond, offered the best pet healthcare, and focused on exceptional customer service.

In 1996, the dream of starting their own clinic came to fruition. Mike and Patti married that July and then opened Riverside Pet Hospital in October. Over the years, he has watched it grow from a husband-and-wife team to the successful practice it is today that employs veterinarians, veterinary technicians and receptionists.

Dr, Korosi was born in Fort Erie and raised in the small town of Simcoe, ON. He always adored animals and had decided that he was going to be a veterinarian by the time he was 10. He and Patti have one daughter who wants to follow in her father’s footsteps and be a veterinarian when she grows up. He also shares his home with 4 Bengal cats, 2 rabbits, 3 fish, and 2 extremely friendly pet rats that he recently adopted from the Toronto Humane Society.

Dr. Korosi enjoys spending time with his family. His hobbies include swimming, gaming, playing Risk, and anything to do with science fiction. He also enjoys furthering his medical knowledge by reading veterinary journals and textbooks and attending yearly conferences to ensure he has the most up-to-date information. His special interests include preventative healthcare, surgery, behaviour, and dentistry.

Dr. Korosi looks forward to meeting you and providing the best possible care for your 4-legged family member.

Dr. Paul Johnston, D.V.M.

Dr. Paul Johnston is a 4th-generation veterinarian, following in the footsteps of his father, grandfather, and great grandfather as a Doctor of Veterinary Medicine. He obtained his Honours Bachelor of Science from Trent University in 1994, his Bachelor of Education from Queens in 1995, and culminated his educational experience by graduating from the Ontario Veterinary College at the University of Guelph in 2000.

Upon graduation, Dr. Johnston practiced 1 year at Mohawk Raceway in Campbellville, ON on standard-bred racehorses, followed by 1 year at a rural practice in Norwood, ON on small animals and horses. Since, May 2002, Dr. Johnston has proudly worked at Riverside Pet Hospital, and he maintains a small horse-only practice in Peterborough.

Dr. Johnston was born and raised in Peterborough, and still proudly calls it his home. Here, he lives with his wonderful wife, Teresa, and 2 very spoiled, yet fabulous children. His 10-year-old daughter plans to be a sarcasm teacher when she grows up, while his 9-year-old son intends to become a video-game specialist. Along with the people in his life, Dr. Paul is surrounded by 3 household pets: Mumford the cat, Barkley the three-legged cat, and the love of his life, Zora, the 6-year-old Chihuahua/Pomeranian rescue dog. Dr. Johnston also owns many standard-bred racehorses that are kept on the family farm just outside Peterborough.

Dr. Johnston enjoys working with the staff at Riverside Pet Hospital very much. His interests at work include surgery, and he has a strong affinity for small dogs/puppies and kittens. Outside of work, his hobbies include racing horses, playing hockey, and coaching his son’s hockey teams. He enjoys spending as much time with his family and friends as possible, and he enjoys the board game Risk.

Dr. Johnston looks forward to working with you and your pet and welcomes you to Riverside Pet Hospital.

Patti Terzian-Korosi R.V.T.
Registered Veterinary Technician

Patti is a registered veterinary technician and established Riverside Pet Hospital with her husband, Dr. Mike Korosi, in 1996.

Patti started her educational career in nursing school, but then transferred to the veterinary technology program at Seneca College. In 1995, she graduated and went on to write her provincial board examinations.

Patti has loved animals since she got her first hamster as a child. She grew up in Mississauga where, as a teenager, she worked at various animal hospitals and pet stores.

Her special interests include pharmacology, exotic medicine, and hospital management.

Patti has a love of learning and continuing her education thorough attending conferences, seminars, and courses. She holds certificates in a variety of veterinary healthcare topics. She also enjoys spending time with her family and pets, reading, volunteering at church, and anything to do with science fiction. She has given talks on pet care at her local school and Scout group. She has also participated in career day seminars for children living at a Toronto women’s shelter.

Patti shares her home with her husband and one daughter. She also lives with a menagerie of pets that includes 4 Bengal cats, 2 rabbits, 3 fish, and 2 recently-adopted outgoing pet rats.

Patti is now a stay-at-home mom but can be found behind the scenes in the area of management and filling in as needed.
She feels privileged in getting to know Riverside Pet Hospital clients and their pets over the past 15 years. She looks forward
to new, future relationships and invites you to “check us out!”

Katie Beatty R.V.T.
Registered Veterinary Technician

Melissa Reinke R.V.T.
Registered Veterinary Technician

Melissa Reinke is a recent honours graduate from the University of Guelph Ridgetown campus. She became a registered veterinary technician in 2011, although she has worked at Riverside since 2007. She has worked in the veterinary field in various capacities for 8 years, including as a receptionist, veterinary assistant, kennel staff, and lab technician. Melissa values education and would like to further specialize as her career progresses. Veterinary dentistry, rehabilitation, and wildlife medicine are avenues of specialization that interest her, and she may pursue some of these in the not-too-distant future.

Melissa is a pleasure to work with. Her easy-going manner and light-hearted nature make working with her enjoyable, and as such she is well-liked by both staff and clients. She is quick to smile and quicker to laugh, and is a valuable member of our team. Like most veterinary technicians, she genuinely has your pets’ well-being first and foremost in her mind.

Melissa has several pets in her life. She has 2 cats, Sam, a 1-year-old male she adopted while at school, and Shakespeare, a 4-year-old rescue kitty with a brain disability. She also has a dog, Little Orphan Annie, an approximately 8-year-old Jack Russell/Beagle cross. She also takes care of her boyfriend’s cat, Loki, and her parent’s cat, Mr. Bean.

In her personal time, Melissa enjoys family and friends, movies, reading, and cuddling with her furry 4-legged family members.

Melissa welcomes you to Riverside Pet Hospital.

Amanda Vail

Amanda Vail is from Ajax, Ontario. She began working at Riverside Pet Hospital as a teenager in the fall of 2007. At Riverside, Amanda is a valued part of our client/pet care team where she does reception and kennel staff duties and assists the veterinarians and technicians with their duties. Amanda finds working in a veterinary practice very rewarding and enjoys the one-on-one relationship that develops between the staff and the pets that come here. She enjoys and takes pride in driving down the street and recognizing the pets out for their walks with their people.

Besides working at Riverside Pet Hospital, Amanda is a student. She graduated from Durham College with a diploma in early childhood education. She is enrolled at Trent University where she is majoring in psychology. Her career goal is one day to become an elementary school teacher.

While work and school take up a majority of her time, Amanda still finds time to enjoy her family and friends, loves listening to country music, eating her favourite cookie – ginger buttons – and enjoying her guilty pleasure of watching reality TV.

Amanda and her smiling face look forward to inviting you to Riverside Pet Hospital and she looks forward to working with your pet.

Jamie Wood

Sandra Whitehouse

Sandra began working as our receptionist at Riverside Pet Hospital in 2003. In 2005, she moved away to Mississauga, where she was a veterinary assistant to a cardiologist and an ophthalmologist at an animal referral hospital. However, we were blessed to keep her as part-time staff here at Riverside on her days off. We were even more blessed to have Sandra return in 2010 to become our full-time receptionist, front office manager, and animal care assistant. The clinic is a better place when Sandra is here.

Sandra is our front line and the first impression clients get when they phone or visit our clinic. Clients see that she is genuine, courteous, and friendly. She truly enjoys her role with the clinic. She has a wonderful sense of humour and an innocence (that staff members will often exploit for a laugh), as well a gentleness about her that shows she really cares about your pet. Sandra is a favourite among all staff here at Riverside.

Sandra has 2 pets in her life: 2 male cats, Victor and Chupa. Victor is her white 6-year-old “little love bug,” and Chupa is a 9-year-old orange tabby who Sandra describes as “CRAZY and very intelligent.” In her spare time, Sandra enjoys cuddling with her boys, travelling to exotic locales, eating pepperoni pizza, cookies and, of course, spending time with family and friends.

Sandra welcomes you to Riverside Pet Hospital with a smile and looks forward to talking with you.

Sarah Fortune