| A deadly fungus that wipes out honeybees
has arrived in Northern Ireland for the first time.
Belfast-based scientists have warned beekeepers in the province
to be vigilant against the disease that has killed huge numbers
of the insect in Spain.
Nosema ceranae infects adult bees when they ingest
its spores, which then germinate in the gut and impair the
bee’s ability to absorb nutrition, particularly protein. It
has caused serious losses of honeybees in Spain linked to
Marie Celeste Syndrome or Colony Collapse Disorder.
The disease was found in north Dublin in 2008 after it was
first detected in six colonies in England and three in Wales
in 2007.
Scientists at Belfast’s Agri-Food and Biosciences Institution
(AFBI)
laboratory confirmed fears that the parasite is here, although
they believe it may have been present for some time as it
was found in four colonies spread across Northern Ireland.
Another strain of the bee-killer - N. apis - was
already present in Northern Ireland’s hives, but N. ceranae
is more aggressive, according to AFBI higher scientific officer
Sam Clawson.
He said the scientists are monitoring the deadly fungus
to prevent it affecting colonies here as seriously as those
in Spain. “In Spain, the impact was very severe, but in other
countries it had no impact at all,” he said.
“It did cause problems there - it was seen as a cause of
Colony Collapse Disorder. However, it has probably
been here for some time. We are monitoring it and, as far
as beekeepers are concerned, it will just be another problem
to watch out for.
“Bees travel from their hives and may contaminate each other
- poor management of hives can play a part. It’s about making
sure they are clean and well-managed - good husbandry in beekeeping.
The message to beekeepers is to be vigilant and have good
husbandry.”
One of the four samples in which the spores were detected
came from attendant worker bees with a queen imported from
the Republic. The other three samples were taken from local
colonies with no evidence of importation. The apiaries are
in counties Antrim, Down and Londonderry.
The scientists examined the samples for the killer bug using
light microscopy and the presence of N. ceranae was
confirmed by molecular techniques to detect species-specific
DNA.
N. ceranae was originally described in 1996 as the
Asian variant of N. apis affecting the eastern honeybee.
An AFBI spokesman said - “Nosema ceranae is considered
to produce a more virulent disease than N. apis, probably
reflecting its more recent association with the western honeybee.
Nosema ceranae symptoms differ from those produced
by N. apis.
“The dysentery and crawling behaviour associated with the
latter infection may not be displayed by bees infected with
N. ceranae. Rather, the symptoms of an infection are
more nondescript and include colony dwindling and increased
overwintering mortality.”
He said that approximately 20% of beekeepers in Northern
Ireland use an antibiotic called fumagillin dicyclohexylammonium
to fight the bee-killing parasite.
“Experimental studies have shown that this treatment is
effective against N. ceranae, although work is ongoing.
Antibiotics, though, will not kill spores in the hive, so
comb changing and a hive scorch are recommended to clear an
infection.
“As with all bee diseases, hygiene, good nutrition and vigilance
are paramount,” he added.
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