The Department of Agriculture, Food and the Marine (DAFM) has said that lead poisoning cases diagnosed by its veterinary laboratory service tends to peak in late Spring and into early summer.
In 2023, there were 20 herd outbreaks of lead poisoning in cattle that were investigated by DAFM’s veterinary laboratory service.
An update published on the DAFM’s animal health surveillance page on Thursday, March 21, noted that cases of lead poisoning tend to spike when animals are turned out to pasture.
While weather conditions remain challenging for grazing, most farmers will be hoping to ramp up spring grazing in the coming weeks.
The update reminded farmers that prevention is the best policy and warned that lead is “highly toxic” to animals.
Lead poisoning mainly affects cattle and sheep, but calves are particularly at risk due to their increased susceptibility and curious nature.
To reduce the risk of lead poisoning, farmers are urged to carefully check their fields and hedgerows for sources of lead such as old car batteries before turning cattle out to pasture and before silage making.
“Hedgerows bounding public roads should be checked carefully for fly-tipping of risk materials. Where identified, sources of lead should be removed and disposed of safely.”
According to DAFM: “Catastrophic losses have occurred on occasion, where discarded batteries have been accidentally incorporated into silage and this silage then fed to cattle.
“From a public health perspective, lead exposure in milking cattle or beef cattle being readied for slaughter has potential risks for the food chain.
“In order to protect the human food chain, cases of lead poisoning are investigated thoroughly, and certain restrictions may be applied.”
Losses due to lead poisoning, not only of animals but also financially, can be substantial for the farmer.
Common sources of lead on farms:
- Lead batteries, including electric fencing batteries;
- Discarded Lead flashing and lead piping;
- Bonfire ash;
- Old lead paint tins and flaking lead paint.
Toxicity can occur within 24 hours of exposure and the clinical signs range from sudden death to blindness, ataxia, head pressing and convulsions.
Lead poisoning can often be diagnosed on clinical signs and finding a source of lead to which the animals had access.
Measurement of lead concentrations in tissue or blood by the local DAFM regional veterinary laboratory, on referral by your vet, will confirm the diagnosis.
Prevention is a matter of not allowing cattle access to sources of lead.
Before cattle are turned out to grass in the spring and at regular intervals during the grazing season, farmers should search the fields for discarded batteries, lead shot, old painted items or other possible sources of lead.
This is especially important in fields bounded by a public road where fly-tipped material may be a potential risk to grazing animals.
Lead batteries should be disposed of carefully in accordance with local authority guidelines. Prior to disposal, ensure that batteries are kept where cattle cannot access them or where they or their leaked contents cannot end up in silage or in a diet feeder.
Other tips to help prevent lead poisoning include:
- Ensuring cattle do not have access to old cars or tractors or leakage from their batteries or sump oil;
- Do not use timber painted with old toxic lead paints, like an old painted door to block a gap or doorway or leave them in areas that are accessible to cattle, especially calves, which have a tendency to lick such items.
- Do not use lead pipes for plumbing, or red lead paint for preserving metalwork.
If a farmer suspects lead poisoning in an animal, they should contact their vet who will be able to advise regarding the diagnosis, and can arrange to have clinical samples tested or a post-mortem conducted on your animal at a DAFM veterinary laboratory to confirm the diagnosis.