Farmers are being urged to be vigilant for signs of listeriosis or 'circling disease' in animals when feeding silage this winter.
Teagasc animal health expert Riona Sayers and nutrition specialist Dr Siobhán Kavanagh have warned there was a higher risk of listeriosis this winter because of extremely difficult silage-making conditions during the summer.
"Farmers who made silage in wet conditions had a higher risk of contaminating their silage crop with clay," said Dr Kavanagh. "If clay got into the silage, there is a higher risk of listeriosis."
Analysis of more than 1,000 silage samples by FBA Laboratories has shown up a higher than normal number of silages with high ash content, which is an indicator of soil contamination.
"Soil contamination is not a widespread problem but it is something that farmers need to be aware of this winter," said Conor Butler of FBA Laboratories"
Around 1.5-2pc of tested samples have had an ash content of 9-12pc, when a normal ash content should be 7-8.5pc."
Listeriosis is an infection caused by the bacteria listeria monocytogenes, which is found in the digestive tracts of mammals. Cattle and sheep affected by listeriosis suffer from encephalitis or swelling of the brain.
The first signs of listeriosis are that the animals appear depressed and disoriented.
They can propel themselves into corners, lean against stationary objects, or circle in one direction. This circling has given rise to the name 'circling disease'.
Facial paralysis with a drooping ear, lip and eyelid can be seen and the animals will often drool continuously.
Eventually the animal will collapse and can appear to be trying to run while on the ground.
Sheep are more susceptible to the disease than cattle, with only a 30pc recovery rate likely.
However, around half of cattle affected recover after antibiotic treatment.
- Caitriona Murphy