Farmers in County Armagh have expressed concern that poultry litter may have been the source for the botulism which killed some of their cattle.
A few weeks ago, I took a call from a farmer who had seen five of his cows drop dead in their field in just three days.
The animals had died of botulism and the farmer, who didn't want to be named, was convinced the source was poultry litter spread nearby.
His call prompted me to investigate and it seems it is a growing problem throughout the countryside.
"First of all, they get unsteady on their front legs, then their back legs, then the animal goes down," said beef farmer Charlie Patton.
I am standing in his yard as he recalls losing several cattle to botulism. It is an uncomfortable memory for him.
"Eventually, it paralyses all their internal organs, their lungs and everything, so they can't breathe and they just pass away," he said.
"It's not nice now to watch because you're helpless; you can do nothing for them."
Charlie's story is far from unique. Last month, I took a call from another farmer. He told me how, just a few days before he phoned me, he had gone to check on his dairy cattle.
Arriving at the field where they were grazing, he found three animals, which had been perfectly healthy just hours earlier, dead. Two more were down. They also died within days.
What connects this farmer's loss with Charlie's, and an ever-growing number of others, is the farmers' belief that poultry litter spread as fertiliser close to their land was the source of the botulism.
DARD (Department of Agriculture and Rural Development) scientists agree that contaminated broiler litter does pose a significant risk to cattle and recognise that there's been a "major increase" in the number of cases in recent years.
Broilers are chickens raised intensively for their meat. Broiler litter is a mix of bedding material, feathers and manure. In its unadulterated form, it is an effective, economical and harmless fertiliser.
There is a problem though.
A modern broiler house will commonly contain more than 20,000 chicks. No matter how well the house is managed, some of them will die. Their deaths, and their carcasses, can easily go unnoticed.
When the litter is later gathered up, it then contains small bones and other parts of chicks which can be the source of a botulism outbreak. If the litter is not ploughed in as soon as it's spread, scavenging animals like foxes and crows can spread the disease over a surprisingly large area.
Brian Walker is a Portadown-based solicitor who has successfully represented many farmers who have lost animals in this way.
He says the current code of practice governing the use of litter as a fertiliser must be replaced with much more robust legislation.
"I am contacted at least once a month by a farmer somewhere in the province that has a problem about botulism," he said.
"It wouldn't be a major problem if the practice directions were fulfilled and the chicken litter was immediately ploughed in, but in many cases it's not."
"If you have chicken litter which is not immediately ploughed in, then you should be liable to prosecution because this is causing your friends and neighbours umpteen thousands of pounds."
Here in Northern Ireland, poultry production is dominated by one company - Moy Park. For them, litter is a massive headache - a 200,000-tonnes-a-year headache. For them, the ideal solution would see no poultry litter being used as fertiliser.
Tony O'Neill is the director of convenience foods at Moy Park.
He said: "We have been working on a solution now for nearly seven years. Our approach is to remove poultry litter from the land. You'll probably have heard of the Rose Energy Project which was to fuel a power station using this litter. That project, if delivered, would remove poultry litter from the land and, by default, remove the threat of botulism which does exist today.
"[The disposal of] poultry litter represents a limitation on our activities in Northern Ireland today. It prevents us growing as fast as we would like to and it is something that we need a long-term solution to to guarantee the future of this business."
Willie Irwin is a farmer - and an MLA. He's raised the issue at Stormont.
"I've had people contact me from all over," he said. "They're very concerned and annoyed that they lose valuable animals and there's no-one there to compensate them or to pay them and it's very hard to prove beyond all reasonable doubt where the disease came from exactly.
"Maybe 95 per cent of farmers abide by the guidelines, but there are those that maybe don't fully realise the dangers that are involved.
"Something has to happen because clearly the guidelines are not being adhered to or are not working. I raised this at the Agricultural Committee and we want to meet with officials to see what can be done."
Moy Park's power plant proposal has been dogged by controversy. It now sits on the desk of the environment minister Alex Attwood. His decision will be closely watched, not only by the poultry industry, but by the entire farming community.