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Endoscopy helps Northwoods Animal Hospital patients

Mark Naniot, Dr. David Theuerkauf, Dr. Michael Franks, ; remove fish hooks ingested by a loon at Northwoods Animal Hospital

​​​​​​​​​​​​​​​​​Donated endoscopy equipment helps Northwoods Animal Hospital patients.​

The Marshfield Clinic Minocqua Center Ambulatory Surgery and Gastroenterology departments recently donated endoscopy equipment to Northwoods Animal Hospital in Minocqua to help veterinarians better treat their patients.

Endoscopy equipment allows doctors and veterinarians to visually examine internal organs and body parts without invasive exploratory surgery, said Dr. Michael Franks, Marshfield Clinic gastroenterologist.

“The advantage of endoscopy over other methods of evaluating the digestive system is that it’s nonsurgical,” Franks said. “The technique allows for visualization of the lining of the digestive system and for taking samples of the lining of these organs, including biopsies. Many foreign bodies in the esophagus and stomach, like the fish hooks we recently removed from a loon, may be identified via endoscopy.”

The Clinic was able to donate the equipment, because it recently upgraded to higher-definition equipment, which gives medical providers better images. The Minocqua Ambulatory Surgery Center now offers the newest technology for its colonoscopy service. “This allows the physicians to see and treat lesions that weren’t readily visible with older models – and to return to the location of lesions, much like the GPS in your car,” said Tom Meyers, manager, Marshfield Clinic Minocqua Center, Ambulatory Surgery Center.

Dr. David Theuerkauf, veterinarian at Northwoods Animal Hospital, is training with Franks on the use of the endoscopy equipment for other animals in his practice.

“We want to give a big thank you to Dr. Michael Franks for working with Marshfield Clinic to secure the donation of this equipment, the time he has taken to set it up and his expertise in training,” Theuerkauf said. “Once we’re finished training, the equipment will help greatly to identify foreign bodies and do biopsies when we suspect problems in the gastrointestinal tract.”

Theuerkauf said it’s beneficial for the animals when veterinarians can do nonsurgical procedures. For instance, loons don’t do well with surgery and likely would not survive a surgical procedure to remove ingested fish hooks. With the endoscopy equipment, Northwoods Animal Hospital was able to identify and remove the fish hooks without doing surgery and the loon was released within two days.

Mark Naniot, of Wild Instincts Wildlife Rehab Center in Rhinelander, brought the loon to Northwoods Animal Hospital and assisted in the endoscopy procedure.

“We can't even begin to tell you how much the endoscopy equipment means to wildlife,” Naniot said. “Animals, such as the loon, would have had to be euthanized in the past in this situation. Doing a very invasive surgery on a highly-stressed loon is not really an option.

Naniot said it’s common for Wild Instincts to receive bald eagles and loons that ingested hooks, jig heads and sinkers. Each year, 15 to 20 loons and 10 to 15 eagles are seen with some type of fishing tackle that has been ingested. Birds are highly sensitive to lead poisoning and will die very quickly if the source of the lead is not removed.

“As rehabilitators, we devote our lives to saving wildlife and have been so frustrated over the years not being able to help animals in this situation. We are so thrilled to now be able to help because of Marshfield Clinic’s generosity,” he said.

A video of the procedure is available at For more information, contact Northwood Animal Hospital, 715-356-3269, or Wild Instincts Wildlife Rehab Center, 715-362-9453.

​​The Marshfield Clinic system provides patient care, research and education in more than 50 locations in northern, central and western Wisconsin, making it one of the largest comprehensive medical systems in the United States.

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