The Department of Agriculture has said that "only a handful" of cattle have died from botulism and humans are not at risk from that strain of the toxin. A department spokesman was speaking after confirmation of the latest outbreak of the disease which has killed a number of animals in west Waterford over the past month.
Last year, an infant in Britain became ill when it was infected with botulism which was thought to have originated in baby food manufactured in Ireland.
Yesterday, the department issued advice to farmers on bovine botulism saying it had noted an increase in the number of suspect cases from different areas reported to its laboratories. The disease is not notifiable.
"It is believed the organism proliferates in decaying organic material, producing toxins that are then taken up by animals," the statement said. "These recent cases have been associated with cattle coming into contact, directly or indirectly, with poultry litter that has been contaminated with decaying poultry carcases."
"While humans may be affected by botulism, it should be noted there are eight known types of the botulinum toxin and that the specific toxins implicated in the conditions in humans are not those normally associated with the condition in cattle.
"It is also generally accepted that humans are resistant to the types of toxin that affect cattle. Furthermore, these toxin types are poorly absorbed from the gastro-intestinal tract and the toxins themselves are inactivated by heat treatment," it added. "The risk to human health from consumption of milk or meat from cattle on farms with cases of botulism, therefore appear to be remote."
Asked about the potential risk to humans from bovine botulism, a spokesman for the Food Safety Authority of Ireland, said human illness could be caused by types A, B, E and F botulism.
He said cattle became ill when exposed to type C botulism and many cases were associated with exposure to poultry litter.
The Department of Agriculture spokesman said there was no indication of any infected cattle getting into the food chain.
There were reports last night that at least one Munster-based meat-processing plant had refused to accept animals which it suspected had come from a farm where animals had become ill from botulism.
The Department also confirmed that a number of cattle had been destroyed but there had been no need to isolate any farm.
In its advice to farmers last night, the Department said farmers were advised to wear gloves, to wash their hands thoroughly after handling poultry litter and to avoid unnecessary contact with the material.
In the context of addressing the animal health issue associated with the identified risk to cattle of using poultry litter, it advised farmers to accept litter only from poultry farmers who had adequate systems in place to ensure all dead carcases were removed from houses on an on-going basis and were stored and disposed of in the correct manner.
It also advised them not to chop litter and to check lands after spreading to ensure the pasture was free of poultry carcases, to use litter on tillage lands if possible and not to allow grazing for at least six weeks after spreading.
It also warned against stockpiling and spreading litter in warm weather, to avoid spreading near waterways and to follow local authority advice on recommended levels of animal manure for land spreading.