Lead poisoning in grazing livestock
Lead poisoning is one of the听most commonly diagnosed听causes of fatal poisoning in cattle. With many herds听having newly听turned-out听stock or听currently turning stock out to grass, it is important to be aware of the risk of lead poisoning and inspect fields before cattle,听especially youngstock, are turned out.听听
By considering what you can do to mitigate the risks of lead poisoning, as well as spotting signs of toxicity,听you can help reduce impacts on your livestock and听the financial impacts to your business.听
Risks听post turn-out听
Data collected by SAC Consulting听has shown that 92.5% of lead poisoning cases are diagnosed during the grazing season.鈥疧f these almost three quarters occurred in听the months of May听and June.鈥疍iagnosis of lead poisoning is usually seen between May and August with highest cases seen听immediately听following turn out in spring months.听
While all ages can be affected by lead poisoning, it is听most commonly seen听in curious calves and younger cattle, as听young cattle tend to听be听most at risk of poisoning due to their inquisitive nature.听To reduce the risk of lead poisoning, farmers are urged to carefully check fields and hedgerows for sources of lead before turning out cattle to grass and throughout the grazing season, as incidences of fly-tipping听on farmland and in rural areas and听are now becoming more common. For anyone with seasonal grazing, it is also important to inspect fields before stock are turned out.听听
Common sources of lead on farm include:听
- Lead batteries from cars and machinery听听
- Electric fencing batteries听听
- Burnt-out cars and bonfire ash听听
- Lead flashing and piping听听
- Flaking lead paint and old tins听听
- Lead shot听听
- Natural lead in soils听听
- Lead mines and surrounding land听
Lead levels in Scottish soils are听generally low, therefore poisoning from grazing is uncommon. However,听in certain areas lead levels can be high, such as near old mine workings or on the site of a burnt-out car.听Foreign objects as listed above can find themselves within reach for livestock very easily, with fly-tipping being a major uncontrolled factor.听
The curious nature of cattle mean that they are highly likely to readily lick or chew on material containing levels of lead.听If there has been an old battery leftover from an electric fence, then a young inquisitive calf is sure to find it.听听
Lead is also palatable to cattle听due to it having a sweet taste with car batteries and batteries from old farm machinery often a higher risk as听electrolytes contained within them can also be palatable.听
Symptoms听of听lead听poisoning听听
Acute听symptoms of lead poisoning include:听
- Blindness听听
- Muscle tremors听听
- Abnormal behaviours (including teeth grinding,听bellowing听and circling)听听
- Seizures and convulsions听听
- Salivation听听
- Constipation/diarrhoea听
- Sudden death听听
Acute toxicity can occur within 24 hours, and clinical signs range from sudden death to blindness. Animals that survive for a few days are dull, blind, anorexic and may become recumbent.听
Lead poisoning听is not always听fatal;听however, it听often presents this way in the short term, with other acute symptoms seen in the rest of the group. Chronic symptoms听include anaemia, foetal deformities and infertility both of which can have a longer lasting effect on herd performance.听听听
The听cost of听lead听poisoning听听
Lead poisoning in cattle causes significant financial losses, driven primarily by high mortality rates. There is testing and veterinary costs as herds听affected require听blood tests and monitoring, adding to听initial听veterinary expenses听and diagnosis.听听
The minimum 16-week withdrawal period causes potential delays in sending animals to market, which could result in loss of market value.听听
There are also the longer-term production losses to consider including slower of stunted growth and increased birth defects and infertility.听听
In 2020,听听a case of lead poisoning where a farmer lost听eight听cattle from a group of 38 after two batteries were found to have been fly-tipped in his field, leaving听eight听calves orphaned. Symptoms displayed in affected animals included teeth grinding, head bobbing and muscle tremors, with animals continuing to be affected for several weeks later.听听
Prevention听
The best defence against lead poisoning is prevention so check fields now for potential sources and remove them.听It听can be as simple as removing old paint and ensuring听animals have no听access to lead flashing听or pipework.听听
Checking听your听grass听fields听prior to turnout听and听frequently听during the grazing period听for batteries or signs of fly tipping can reduce risk to stock.听This is听particularly important听where听pastures听haven鈥檛听been grazed recently or on seasonally rented听ground you are unfamiliar with.听听
Ensure that portable electric fence batteries are collected from grazing and or silage fields. If you are using an electric听fence,听ensure that the battery is not in reach of stock.听听
Where听an area of grassland has听a听high lead content, ensuring grass is not over grazed can minimise risks to stock as it reduces soil intake.听For areas where a bonfire or vehicle has burnt, ensure that the ash is removed along with a layer of the soil if you are unable to restrict access to this area.听听
If you suspect lead poisoning, consult your vet听immediately听and investigate the potential source of poisoning to prevent further cases.听听
5 top tips听
- Lead is a highly toxic. It is the most common cause of cattle poisoning.
- Highest incidences occur in Spring following stock turnout.
- Identify and remove source of lead and prevent access by livestock e.g., check fields for discarded vehicle batteries.
- In areas with naturally high soil lead content, don鈥檛 graze pasture too short.
- Stay vigilant for signs of fly tipping throughout the grazing season.
Useful links听
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Kirsten Craig, Agricultural Consultant,听Kirsten.Craig@sac.co.uk听
Posted by SAC Consulting on 18/05/2026
