Perth Zoo’s female Ring-tailed Lemur, Tiana, was recently admitted to our vet hospital after her carers noticed some unusual behaviours.

Over the years, our primate and veterinary teams have been monitoring the 7-year-old for reproductive and fertility issues. 

Some of you may remember, a team of human gynecological oncology specialists assessed Tiana back in 2022 for health issues.

Perth Zoo Veterinary Services Manager, Dr Rebecca Vaughan-Higgins, said: “As a primate, there are many similarities between human and Ring-tailed Lemur’s anatomy."

“A few years ago, our wonderful ‘human doctor’ colleague Professor Yee Leung came to assist in investigating Tiana’s reproductive system. 

During the procedure in 2022, we investigated and removed a small polyp on her vaginal wall that appeared to be causing fertility issues.

Following this procedure, the team have been closely monitoring Tiana for any further changes.

Her latest clinical signs suggested something wasn’t quite right and further assessment of her reproductive system was needed. 

During a check-up under general anaesthetic, the team used a small telescope to take a look at Tiana’s reproductive system, while also drawing blood, and taking tissue samples for further testing.

“Unfortunately, we found another small polyp during her most recent procedure which may be compromising her fertility and not allowing the normal passage of sperm," Dr. Rebecca said.

Sperm plugs occur after mating in some primate species and serve as a physical barrier to prevent other males from mating with the same female, to increase the chances of the original male's sperm fertilizing the egg.  They are temporary barriers formed in the female's reproductive tract after mating and aren’t normally a cause for concern.  However, Tiana seems to have unusually large sperm plugs which she retains and then becomes quite uncomfortable.  It is thought the polyp may be obstructing the normal flow of the sperm, leading to the formation of the uncomfortable, large, sperm plug.

“We’ve removed the polyp and will await further test results to help determine the best treatment plan for her moving forward.”

Following the procedure, Tiana recovered in her warm bed and enjoyed plenty of cooked pumpkin once she woke up.

Tiana’s keepers will continue to keep an eye on her over the coming weeks as she returns to tip top condition!