“A fish with a glass eye” sounds like the punchline to a
joke that starts with an angler and an optician walking into a bar.
But two rockfish at the Vancouver Aquarium in Canada are now
sporting bright yellow ocular prosthetics, thanks to a technique honed in
Seattle, USA, the
Bulletin reports.
The fish, who each lost an eye to disease, were restored to
their former good looks by the operation. The primary goal, however, was to
prevent them from being harassed by other fish, which seem to view an empty eye
socket as a sign of weakness, said Seattle Aquarium veterinarian Dr Lesanna
Lahner.
“There’s an aesthetic piece, but my main concern is fish health,” said Dr Lahner, who has been fine-tuning the procedure over the past few years.
A handful of fish at the Seattle Aquarium have received the
implants, and Dr Lahner assisted Vancouver vets with their one-eyed rockfish
last month.
The staff at the British Columbia aquarium was very worried
about a copper rockfish that had an eye surgically removed after a cataract
rupture. The 6-pound fish started avoiding its tank mates and hiding in nooks
and crannies, said Dr Martin Haulena, the aquarium’s head veterinarian.
“Fish were picking at it,” he said. “Its fins were tattered,
and it was really getting banged up.”
With life spans that can exceed a century in the wild,
quality of life is particularly important for captive rockfish.
During the 20-minute procedure, a technician bathed the
anaesthetised animal’s gills and skin with water, while Dr Lahner popped the
prosthetic into the socket and coached Dr Haulena on the best way to thread
fishing line through bone to hold it in place.
The glass eyes are the kind taxidermists use in trophy trout
and salmon mounted for display. Dr Lahner glues two of the flat-backed inserts
together to form a sphere.
Fake eyes for fish aren’t new, she pointed out.
The idea was pioneered in the 1990s by Drs Craig Harms and
Greg Lewbart, Dr Lahner’s mentors at North Carolina State University. They
developed a surgical procedure tailored for ornamental koi. Collectors will pay
tens of thousands of dollars for a single, exquisitely patterned specimen, and
there’s little tolerance for one-eyed fish in an industry built around beauty.
Dr Lahner adapted her mentors’ method to work in cold-water
species, eliminating an adhesive that can cause inflammation and devising a way
to anchor the prosthetic with fishing line and titanium clips.
“It’s still a work in progress,” she said. “I would not say
by any means this technique is perfected.”
Fish with a missing eye used to be routinely euthanised at
aquariums because they were considered unsightly, Dr Haulena said.
Read more HERE.
(IAF1501)
The Aquaculturists
This blog is maintained by The Aquaculturists staff and is supported by the
magazine International Aquafeed which is published by Perendale Publishers Ltd
For additional daily news from aquaculture around the world: aquaculture-news
No comments:
Post a Comment