Great uncertainty still surrounds the origins of the outbreak of H5N1 avian flu at the Bernard Matthews turkey farm at Holton, Suffolk.
Contamination by an infected wild bird is still the most widely accepted explanation, though it remains a mystery as to how it breeched the bio-security at the site.
The Times newspaper reports that large gatherings of seagulls had been spotted at the farm in recent days. It suggests that infected droppings may have landed on wood shavings used for bedding that is stored outside.
Another possibility is that a smaller bird, such as a sparrow, may have become infected and got into the shed through a ventilation shaft.
But the Royal Society for the Protection of Birds is far from convinced.
“We’re not saying wild birds are not responsible, but it’s a little surprising under the current weather conditions,” said RSPB director of conservation Mark Avery.
He said it was too early and too mild to point the finger decisively at migrating birds.
“This time last year cold weather in Russia pushed the birds further west and you could almost see it (avian flu) spreading across Europe,” he told FWi. “This year it has not been cold enough.”
The other big risk came from birds migrating north again from winter feeding grounds in North Africa, but that would not start until March or April.
Mr Avery said it was possible that there was avian flu in UK domestic birds, though that too was unlikely. Ongoing monitoring had revealed nothing suspicious – no sudden increase in die-offs and no positive results from routine testing.
“It is a genuine mystery. If it is wild birds that have brought the disease, it’s pretty unlucky that it arrived at this farm. One would have thought outdoor flocks in the area would have been much more susceptible.”
The other possible source of contamination is from lorries or people returning from an infected area.
Much has been made in the media about the fact that Bernard Matthews also has poultry units in Hungary, which is where the last case of H5N1 was reported in mid-January.
The company denies this is possible.
One report also suggests that the Bernard Matthews site may have been the victim of industrial sabotage. Others believe a worker may have accidentally brought infected food or faeces in on clothing.
DEFRA deputy chief vet Fred Landeg insists that all avenues of investigation are still open.
“It is possible that it is wild birds,” he told Radio Four’s Farming Today programme on Monday (5 January). “But we have an open mind and are considering all potential routes of introduction.”
A DEFRA spokeswoman said scientists were currently investigating the precise make-up of the H5N1 virus found at Holton and seeing if it is directly linked to the strain found in Hungary
For more information see:
FWi Avian Flu special reportRichard Allison, Poultry World editor, blogs on impact on Bernard Matthews brand
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