Horse Chestnut
Aesculus hippocastanum
Horse
Moderate
Get veterinary advice the same day and remove access. Significant consumption of conkers or young buds/leaves in spring.
Equio informs, it does not diagnose. When in doubt, call your vet.
What to do now
- Antidote
- No specific antidote. Symptomatic and supportive treatment.
- Time to signs
- A few hours to 24 hours.
- Prognosis
- Good if treated promptly, rarely fatal unless digestive complications (obstruction) occur.
- Call the veterinarian if massive ingestion is suspected.
- Monitor for signs of colic.
- Administer activated charcoal if recommended by the veterinarian.
Its ID card
- Height
- 15 m – 30 m
- Flowering
- April to May.
- Toxic parts
- Conkers (seeds), buds, young leaves, bark.
- Toxin
- Saponins (Aescin) and glucosides (Aesculin).
- Habitat
- Public parks, avenues, gardens, large farmyards.
- Soil indicator
- Deep, moist soils.
- Regions
- Europe, North America
- In hay
- Not reported
- Palatability
- Moderate. Some horses are attracted to conkers, while others ignore them completely due to bitterness.
When the risk rises
September-November (conkers), March-April (buds).
Spotting it in the field
Sweet Chestnut (whose fruits are edible in small quantities; has a very prickly, hedgehog-like husk). — smell : odorless.
- Large, imposing tree.
- Large palmate leaves (5 to 7 leaflets) resembling fingers.
- Upright clusters of white or pink flowers.
- Non-edible fruits (conkers) enclosed in a spiny green husk.
Signs to watch for
Acute toxicity.
Dose : Difficult to determine precisely, but ingestion of several conkers or a significant amount of young leaves/buds can be problematic.
- Moderate to severe colic
- Diarrhea or constipation
- Muscle tremors
- Stiff and uncoordinated gait
- Pupil dilation
Who is affected
Other species : Toxic to dogs (conkers) and humans.
In pregnant mares : not specifically documented.
Getting rid of it
Method : Remove fallen fruits. If necessary, fence off the tree.
- Collect fallen conkers from paddocks and pastures.
- Avoid planting horse chestnuts in areas accessible to horses.
- Closely monitor horses during the conker-fall season.
Frequently asked questions
Can Equio identify Horse Chestnut from a photo?
It can help organize visual clues, but plant identification must remain cautious when horse health is at stake.
Is Horse Chestnut dangerous in hay?
Hay risk is not always reported for this entry, but suspicious forage should still be isolated until checked.
This page is informational. If ingestion is likely, if signs appear, or if the horse is fragile, contact a veterinarian immediately.