Although she needed extra calories, Mingo the malnourished stray could swallow only one piece of kibble at a time after being rescued from the streets of Philadelphia's Frankford section two summers ago.

Mingo would also hack after drinking, and her bark became raspy. On antibiotics for what seemed like a routine case of kennel cough, the wire-haired, brindle terrier was plucked from the city shelter by the Philadelphia Animal Welfare Society (PAWS), which finds homes for cats and dogs that appear particularly adoptable.

"She was a sweet, affectionate dog that seemed easy to place," recalled PAWS executive director Melissa Levy. "We never could have imagined how complicated her case was going to be."

Within days, the year-old dog was gasping for air and refusing food. She was brought to the Veterinary Specialty and Emergency Center in Philadelphia. Mingo had a fever, and her blood work showed high white blood cells - indicating infection - and mild anemia. X-rays revealed pneumonia and a pinched trachea.

Given a poor prognosis for survival, the little dog was hospitalized on oxygen, IV fluids, and antibiotics, with "do not resuscitate" orders.

The next day, an endoscopic examination of Mingo's narrowed trachea showed a band of scar tissue strangling her "windpipe" to about a quarter of its normal diameter. Her esophagus, which runs parallel, appeared normal.

Mingo was taken to surgery, where two constricted tracheal rings - cartilage encircling the trachea - were removed. She recovered well, and was discharged to a foster home after a few days.

Back at the Veterinary Specialty and Emergency Center a week later, Mingo was coughing more, regurgitating, and "reverse sneezing" (which produces inspiratory nasal spasms). X-rays showed resolving pneumonia. Doctors continued antibiotics, and added a medication that dilates the airways, and another that hastens GI motility to prevent regurgitation.

But within weeks, Mingo's hacking was more persistent, and she was now hypersalivating and gagging. She became sluggish. There was a pustule on the back of her neck, filled with fluid.

Endoscopy revealed mild tracheal collapse, which could explain her chronic cough. And it showed a dilated esophagus - or "megaesophagus" - which often leads to retching and regurgitation.

Megaesophagus can be congenital. Or it can be the result of neck trauma. It is sometimes associated with underlying disease: Perhaps Mingo suffered from hypothyroidism? Or lead toxicity? Or neuromuscular dysfunction?

A CT scan of Mingo's chest showed her chronic lung issues to be the possible result of scarring rather than pneumonia.

While Mingo recovered from anesthesia, a nurse noticed foreign material poking out of her neck lesion.

The solution:

Doctors surgically removed what turned out to be a rubbery band nestled deep within Mingo's neck. Perhaps the remnants of a puppy collar, it completely encircled her neck.

During her two months off the street, Mingo's problems had snowballed. Her chronic cough, her aspiration and gagging, even her slobbering, could likely be blamed on an embedded collar.

How does a collar embed? Puppy or kitten grows; collar does not. Unfortunately not rare, embedded collars are typically seen in younger, growing animals.

"Who knows how long Mingo had that there, where over time it just migrated right through?" said Cara Horowitz, a veterinarian at the Veterinary Specialty and Emergency Center.

Embedded collars cause infected neck wounds that tend to be severe and noticeable. In Mingo's case, the ligature was thin and taut enough to implant completely within the tissues and remain unseen. As Mingo grew, muscle and skin grew over it. It even cut right through Mingo's jugular veins. Responsible for draining blood from the head, Mingo's jugulars were replaced naturally by newer, smaller vessels.

Last December, shortly after Mingo's recovery from surgery, Mingo found a "forever home" with Erika Schoof of Lansdale, who had followed the pup's story online.

A year later and four pounds heavier, Mingo is now doing well there. But she is not out of the woods. After persistent coughing and regurgitation, Mingo was diagnosed over the summer with laryngeal paralysis, a malfunction of the nerves controlling the larynx.

The embedded collar had likely destroyed the nerves that open the cartilages to allow air flow through the trachea. Veterinarians performed surgery to pin back these cartilages so Mingo could breathe better. After surgery, Mingo was a new dog.

However, Horowitz cautioned, "she is a dog that likely has permanent nerve damage with continued risk of regurgitation and aspiration."

Sure enough, Mingo has been plagued lately by coughing, reverse sneezing, hard swallowing, and aspiration pneumonia. Endoscopy of her nasal passages and stomach are planned.

Still, despite her problems, Mingo is a happy dog. She plays with the Schoofs' other dog, Milo. When Mingo overdoes it, Schoof staves off fits of reverse sneezing by calming her. To minimize regurgitation, she spoon-feeds Mingo, and then holds her upright for 10 minutes afterward.

"There is nothing I wouldn't do for Mingo," Schoof said. "She is such a good dog and she deserves the best life."

Joan Capuzzi is a small-animal veterinarian at Dutton Road Veterinary Clinic in Philadelphia. jpcapuzzi@outlook.com