Vet warns of hemlock threat to cattle
© Adobe Stock South-West veterinary practice Tyndale Vets is warning farmers to be aware of hemlock poisoning, as the prolonged dry weather is leaving the plants’ roots exposed and easier for livestock to access.
Vet Kirby Dobson recently attended a farm near Bristol, which lost eight cattle to hemlock poisoning, and said this was the second case in a week, sparking concern.
“When I got to the farm, seven out of 42 cattle were already dead and another was having seizures as a result of hemlock poising and needed shooting,” she told Farmers Weekly.
See also: 4 plants poisonous to livestock: How to spot and deal with
Cattle poisoned by Hemlock © Kirby Dobson
Dr Dobson added that because of the prolonged dry weather, cattle are going deeper into ditches for water, bringing them into contact with exposed hemlock roots.
“The farmer in this case had done everything right, and the cattle had silage and water troughs.
“Cattle are just naturally inquisitive animals and the roots are particularly tasty for them,” she added.
She advises farmers to be mindful of possible hemlock poisoning as it can also occur after ditch dredging and removal of the plants, which livestock can consume.
The plant, she adds, has characteristic tuber roots and the flower itself can look similar to cow parsley, though the stem is firmer and woody.
Clinical signs
Early clinical signs of hemlock poisoning include:
- Nervousness
- Trembling
- Muscle weakness
- Respiratory distress
- Drooling
- Dilated pupils
- Paralysis.
Hemlock poisoning can affect both cattle and sheep. Death can occur within hours of ingestion due to respiratory failure.
Hemlock can rapidly spread in pastures and fields and along waterways, making it difficult to control once established. It thrives in moist, disturbed soils.
“Please be vigilant and check any ditches for hemlock prior to putting livestock in the field,” said Dr Dobson.
Those handling and removing the plant are advised to wear gloves and farmers are reminded that it is also still toxic if bailed into hay.
AHDB advice on prevention
The AHDB advice to prevent hemlock from growing is to maintain healthy, dense pastures to outcompete hemlock and other weeds.
Farmers should also monitor ditches and field margins for signs of hemlock and remove them before seed formation.
Removed plants should be disposed of safely to prevent seeds from spreading.
This includes burning or bagging, and disposing the plants in a landfill site.