Photos: Vasectomy conducted on Nairobi lion

The lion that underwent the surgical procedure was 3 years old. [Courtesy of KWS]

In Africa, there were more than 200,000 lions many years ago. Today, there are about 20,000 lions on the continent, a report by Ewaso Lions, a Kenyan organisation dedicated to lion conservation, says.

The procedure was carried out at the KWS veterinary clinic.

"The orphanage acts as a refuge site for stray or orphaned animals in the parks. In one cage, we had one lion and three lionesses. The animals had reached the mating stage, and the male one had begun showing signs of desire to mate. To prevent inbreeding, we decided to conduct vasectomy on the lion," a Communication officer at KWS said.

"That would ensure the population in the cage is controlled."

KWS said the surgical procedure on the lion took three hours, from 9am to around noon on Thursday.

"The lion was darted with an anaesthetic drug to immobilise and make it insensitive to pain. The surgical procedure to sterilise it was conducted by qualified veterinaries," KWS said, estimating that it would take one week for the animal to heal.

"As part of post-operative care, we'll be monitoring the lion daily to ensure it heals properly," KWS said.

"During the three-hour surgery, the anaesthetic drug wore out and the veterinaries had to act fast to immobilise the lion. They administered more anaesthetic drug to allow them complete the procedure," KWS said.

KWS says the surgical procedure lasted three hours. [Courtesy of KWS]

For consent to be given for a wild animal to be sterilised, officers in charge of an orphanage write to the leadership of the veterinary department, who visit the animal cage, and upon examination of the site and the said-animal, issue or reject the request.

Reasons for seeking to sterilise an animal must also be clearly stated.

If a surgery request is approved, the animal is taken to the veterinary services clinic, where the procedure is conducted.

Veterinaries say castrated lions lose their puffy hair because, upon the removal of their testicles, they lose the testosterone that gives them their mane. The more testosterone they have, the bigger and darker their hair.

This not only signals that the lions are fertile, but also makes them look bigger and more ferocious. This is an attractive feature to lionesses.