Zane: The chimp who needed a hernia repair
How the Detroit Zoo and doctors helped a chimpanzee rejoin his community.
When Ann Duncan, D.V.M., director of animal health at the Detroit Zoo, noticed that one of the newborn chimps wasn’t being picked up by his mother, she started to worry.
“Although we encouraged Chiana to pick up Zane, the youngest of the 12 chimps, some female chimps have stronger maternal instincts than others,” said Duncan.
Duncan and other caretakers keep careful watch of all newborns, so when Zane, born in January 2020, wasn’t being carried by his mother, the team decided to examine him. They took his temperature, warmed him up and gave him a bottle. But when returned to the enclosure, Chiana remained disinterested in the baby.
“In the early weeks, we never set him down,” said Duncan. “We set up an incubator and took care of Zane in view of the other chimps.”
Then one day, when Zane was five weeks old, Duncan noticed he had an inguinal hernia, prompting a call to University of Michigan Health C.S. Mott Children’s Hospital for help.
Studying chimp anatomy
Inguinal hernias occur when tissue pushes through a weak spot in the groin muscle, causing a bulge.
The chimp looked healthy and didn’t show any signs of discomfort, but when Duncan examined the hernia with ultrasound, she noticed the bulge contained Zane’s bowel loops. Although Duncan’s veterinary team is able to perform surgery, they didn’t have all of the equipment and experience needed to carry out something this complex.
“I thought a pediatric surgeon would be the best person for the job,” said Duncan.
Marcus Jarboe, M.D., the director of minimally invasive surgery at C.S. Mott Children’s Hospital, said when he was approached about performing a hernia repair on the zoo’s chimp, he was excited.
“I thought it was such a cool opportunity. However, I had never performed a hernia repair on a non-human before,” said Jarboe. “So I wanted to recruit Dr. Hirschl because of his clinical experience. I knew between the two of us, we could figure this out.”
Ron Hirschl, M.D., a pediatric surgeon at C.S. Mott Children’s Hospital, would join Jarboe and two pediatric anesthesiologists, Ashlee Holman, M.D., and Anila Elliott, M.D., to see the surgery through after conducting a literature review of primate inguinal hernias.
“We only found one paper on the topic from a long time ago, but given Zane was also a primate, we figured the anatomy would be similar. So, we grabbed some of our own equipment that we use for training and got ready to perform the first-ever laparoscopic inguinal hernia repair on a chimp,” said Jarboe.
A laparoscopic procedure is one where the surgeon can operate on the abdomen or pelvis with only a small incision and a camera to aid their view. Jarboe, known for his innovative incision-less hernia repair method using just a needle, uses ultrasound as his camera.
Duncan’s team strapped their endoscopy tower into their van and transported it to the hospital the day before the surgery.
“As a zoo vet, we call on experts in human and animal medicine often to help us take the greatest care of our animals, from surgeons and enterologists to allergists and reproductive professionals,” said Duncan. “But working with Dr. Jarboe was a special treat. He was wonderful.”
When the big day arrived, Zane was initially sedated intra-nasally, then put on anesthetic gas. Via ultrasound, Jarboe’s team discovered an inguinal hernia on the other side of the chimp’s abdomen that hadn’t been protruding yet and was able to repair both. Thankfully, the two-hour repair was successful, and Zane was able to make a full recovery
Rejoining the community
“The next step was to help Zane rejoin the chimp troop-- we needed to choose a surrogate mother, and train him to bottle feed since a surrogate mother wouldn’t have milk,” said Duncan. “Having a surrogate mother and re-acclimating to the chimp family would be essential for him, since chimps need to know they’re chimps and be living with each other.”
The team talked with several chimp experts to make this process successful for Zane.
Eventually, not to the zoo team’s surprise, a chimp named Trixi began showing strong interest in the infant chimp.
“Fifty one year old Trixi is the matriarch of the troop; she’s the most respected and the decision-marker,” said Duncan.
When they were introduced, the zoo’s oldest chimp reached through a shift door for Zane and that was all it took to bring the baby back into their family. She helped care for Zane and other chimps followed, like Bubbles, the second oldest chimp in the community at 50 years old. Both Trixi and Bubbles would take turns carrying and playing with Zane, and eventually he made a friend. Jane, the second youngest chimp, notably born on Jane Goodall’s birthday, likes to hold Zane’s hand and show him around the enclosure.
“She’s a great older sister to Zane, and it’s because of the chimps that stepped up like her and working with C.S. Mott Children’s Hospital that Zane has been able to live the life he’s meant to as part of his troop,” said Duncan.