Lead poisoning impacts cattle in Saskatchewan every year, potentially killing multiple animals in a herd. Not only is there the concern associated with losing cattle, but there is also potential for lead to enter the food chain – because of this, testing is required in lead poisoning cases to protect public health.
Dr. Vanessa Cowan, toxicologist at Prairie Diagnostic Services, has seen several confirmed cases of lead poisoning this year, with five being in the past month. She says the most well-known source of lead poisoning is automotive batteries. These batteries are likely remnants from old vehicles or machinery and may have been in the pasture for years unnoticed. However, these are not the only source of lead. Dr. Cowan says that other sources like old buildings with lead paint, old bullets, or old oil and gasoline products may be consumed by cattle and could cause lead poisoning.
Lead poisoning is often associated with cattle being out on pasture. Dr. Cowan said the first case of 2025 was identified in March, with most cases being seen May through July, when cows are grazing. Once the cattle are on pasture, they will find a lead source if it is there. Although commonly seen in cattle on pasture, Dr. Cowan advises that lead poisoning can occur year-round, especially as more producers move towards extensive wintering practices.
If you are concerned about the potential of lead poisoning in your herd, there are a few signs to watch for. These include blindness, abnormal behaviour, walking in circles, pressing their heads into fences, bellowing excessively and muscle twitches or full body seizures. Or you may just find a few dead cattle that were otherwise healthy last time you checked them. Some of the signs of lead poisoning mimic Sulphur toxicity or polio. It is important to contact a veterinarian and have them perform a necropsy and histopathology to determine cause of death.
Dr. Cowan said that the first thing to do if you suspect lead poisoning is to identify the source and remove it from the pasture, so more cattle do not get into it. If the source is from paint on a building, you may need to fence the building out. Cowan says that it is also essential to get your veterinarian out on the farm to help with diagnosing the lead poisoning. She said that there are few treatments available for lead poisoning, so animals with severe cases may need to be euthanized. However, some animals could stay on farm and undergo follow-up testing to see if the lead decreases in their body over time.
Overall, prevention is the best treatment when it comes to lead poisoning. Before turning your cattle out onto a new pasture, take a couple minutes to scout the pasture and look for anything that could be a source of lead. Remove those sources if possible, or fence them out, to prevent cattle from licking or consuming them.
For more information, call the Agriculture Knowledge Centre at 1-866-457-2377.