Specialist helps Gloria to see again
Published: 22nd Aug 2016A last-ditch attempt to save the eye-sight of a rare primate has been successful.
A last-ditch attempt to save the eye-sight of a rare primate has been hailed a success.
Gloria the Paignton Zoo pygmy slow loris had double cataract surgery thanks to veterinary ophthalmologist Jim Carter, from nearby Abbotskerswell Veterinary Centre.
Ghislaine Sayers, Head of Veterinary Services at Paignton Zoo Environmental Park, explained: “Gloria arrived at Paignton Zoo in July 2014 and already had cataracts in both eyes. Over the last two years these cataracts have become more severe - the lenses have become more opaque and the cataracts have filled more of the lenses.
“Over the last six months it has become progressively more difficult for her to find live insect food in her enclosure, while introductions between herself and male lorises for possible breeding have been fraught with problems because she can’t see.
“The only option was to carry out surgery to remove the opaque lenses, allowing light to get to the retina – it was the only way to restore her sight.”
The International Union for Conservation of Nature (IUCN) classifies the species as Vulnerable. Paignton Zoo has a larger than average collection of pygmy slow loris, with a total of 7 animals at present. This includes one pair with one youngster, plus four single animals that could form breeding pairs.
Ghislaine again: “Slow lorises have large eyes because they are nocturnal and they have a very big light-reflecting area at the back of the eye to maximise the available light at night, but as far as I know they are not prone to eye problems.”
The surgery was carried out at South Devon Referrals by Jim Carter. First he performed an ultrasound check of the eyes to make sure there were no other problems which would prevent the cataract surgery from being effective.
Ghislaine: “She had a general anaesthetic followed by a procedure called phacoemulsification, during which the lens of the eye is emulsified with ultrasound and removed from the eye by irrigation and aspiration, to be replaced with a balanced salt solution.”
The anaesthetic, pain relief, intravenous fluids and antibiotics were provided by Ghislaine and Paignton Zoo vet nurse Kelly Elford.
“As she came round from the anaesthetic we had to keep her warm and give her glucose because small animals with a large surface area to body volume often lose body heat during anaesthetics. Small animals also have a high metabolic rate, and if they don’t have food for a period of time, their blood glucose can drop.”
Gloria will have antibiotic and anti-inflammatory eye drops for two weeks, pain relief and oral anti-inflammatories for a month and oral antibiotics for a couple of weeks. “This should prevent her from rubbing her eyes too much where the tiny sutures are and stop the hole in the cornea from becoming infected until it heals.”
She had a check-up by Jim after one week and is being seen daily by the Zoo’s vets or vet nurses. Ghislaine: “Focussing on objects very close to her may be difficult now she has no lenses, but she should have good sight otherwise.”
There is a European Endangered species Programme for pygmy slow loris. This small nocturnal primate comes from the forests of South East Asia, where it lives on a diet of insects, fruit, slugs and snails.
The animals have a comical and endearing appearance which has led to them becoming victims of the illegal pet trade, though their toxic bite and strong odour make them very bad to have around the house.
The Vietnam War nearly wiped out this species of loris as forests were burned or
defoliated. The destruction of forests continues today due to agriculture and development. The pet trade is another serious threat.