Fearless Nicki Grint placed a series of needles around the hind paw of 11-year-old Asiatic lion Lucifer at Paignton Zoo.
Lucifer, who weighs almost 30 stone (190kg), previously had a tumour removed from the foot, with wound failing to heal properly.
Zoo animals are not commonly treated with acupuncture and Lucifer is the first at Paignton Zoo to undergo the procedure.
This is because animals must remain completely still throughout – meaning they need to be under general anaesthetic.
Ms Grint, a specialist in veterinary anaesthesia and analgesia, has previously only used acupuncture on dogs, with Lucifer her first cat patient.
“We are using acupuncture to decrease pain and improve blood flow to the site, helping the healing process,” she said.
She inserted needles at 1in (2.5cm) intervals around Lucifer’s wound in a technique called “ringing the dragon”.
The needles remained in Lucifer’s foot for around 15 minutes, while other experts examined the wound.
Jo Reynard, veterinary associate at Paignton Zoo, said: “We’re using gas anaesthesia and all the usual medical painkillers. The acupuncture is simply being used opportunistically, as an adjunct to conventional therapy in the hope that it might help the wound heal.”
Lucifer was given his name because his number in the computerised Animal Record Keeping System is 666.
He recently arrived in Devon to join two females, mother and daughter Indu and Maliya, at the zoo.
Asiatic lions are classed as endangered by the International Union for the Conservation of Nature.