Nassau-Suffolk Animal Hospital

William Haagenson, DVM, Associate Veterinarian

DVM, Ohio State University


Dr. William R. Haagenson, a graduate of the Ohio State University College of Veterinary Medicine, has been associated with Nassau-Suffolk Animal Hospital since 1992, and was past Medical Director. Although he treats all breeds of animals, he is known particularly for his expertise in treating English Bulldogs and their unique medical conditions. Dr. Haagenson has been recognized by several bulldog organizations for his exceptional knowledge and treatment of this breed. He has received a number of awards, most recently from the Long Island Bulldog Rescue, and has been consulted on issues relating to this breed from Vancouver, Las Vegas, and throughout the United States. Dr. Haagenson has been invited to do veterinary relief work in Bermuda and to participate in a spay and neutering program for the Humane Society in Belize.

Dr. Haagenson is known as an especially concerned and diligent veterinarian, a skilled surgeon, and an expert diagnostician. Always available to his clients and patients, he is a strong advocate for the health and well-being of all animals. He is a firm believer in educating the public in proper animal care. In the past, he demonstrated a spay procedure at the New York State Fair in Syracuse.

He has served as Secretary-Treasurer of the Long Island Veterinary Medical Association, is a member of the New York State Veterinary Medical Society, and of the American Veterinary Medical Association. He attends numerous regional and national conferences and educational seminars throughout the year, most notably the North American Veterinary Conference, an international event.

For the past 10 years, Dr. Haagenson has been a board member of the Board of Zoning Appeals for the village in which he lives, also serving as a Village Trustee for 20 years before that. He is a board member of the Business Improvement District and a member of the Chamber Of Commerce. In addition, he presented the importance of veterinary medicine to students at Career Days at a state university and at a local high school. Dr, Haagenson actively serves the community in any way that he can. He is married, has 2 grown children, twin granddaughters, and Cavalier King Charles Spaniel.


Specialty Care

Sometimes sick or injured pets need the care of a veterinary medical specialist. When that happens, VCA specialty hospitals work closely with the general practitioner veterinarians who refer cases to us in order to provide seamless veterinary care to your pet. When your pet is facing any kind of serious illness or injury, our specialty referral hospitals will provide the compassionate and expert care your beloved pet needs.

Our goal is to make sure that when you and your pet are in need that you have access to board certified specialists who are up to date on the very latest developments in their field. In our state of the art hospitals, our specialists also have access to the most sophisticated diagnostic and treatment tools and techniques from ultrasonography and endoscopy to CAT scans and even MRI.

As part of the VCA family, we have over 83 specialty hospitals across the US and Canada which provide referral specialty care, so there may be one near you. Our specialized services include: behavior, cardiology, critical care, dentistry, dermatology, integrative medicine, internal medicine, neurology, oncology, ophthalmology, radiology, rehabilitation, reproduction, and surgery.

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Emergency Care

If your pet is experiencing a medical emergency when our hospital is closed, you may take your pet to either of following veterinary emergency hospitals in our vicinity:

New York Veterinary Specialty and Emergency Center
2233 Broadhollow Rd. (Route 110)
Farmingdale, NY  11735
Open 24/7/365

Veterinary Referral & Emergency Center of Westbury
609-5 Cantiague Rock Road
Westbury, NY 11590
Phone: 516-420-0000
Open 24/7/365