- Distinguishing features
- Trees or shrubs with thick twigs and opposite, palmately compound leaves with 5-7 leaflets; flowers in clusters, in some species conspicuous with white or colored petals; fruit a globular spine-covered capsule containing 1-3 large, glossy, chocolate-colored nuts, each with a tan or whitish scar.
- Horse chestnut are trees and shrubs with palmately compound leaves with five to seven serrated leaflets. The inflorescence is a panicle with large, erect flowers which are yellow, whitish yellow, or red in color. The fruit-like capsule contains one to three seeds.
- Geographic range
- Found in eastern and western parts of North America, horse chestnut generally does best in rich, moist woodland soils. However, some species have adapted to drier conditions.
- Toxic principle
- Young growing sprouts, leaves, and seeds contain the glycosides aesculin and fraxin. Five bioactive triterpene oligoglycosides, the escins, are found in the seeds of Aesculus but their toxicity has not yet been determined.
- A dose of 0.5% body weight produces severe poisoning in calves. Disease is typically self-limiting because most species will decrease consumption at the onset of clinical signs.
- Clinical signs
Signs of poisoning are seen approximately 16 hours after ingestion of a toxic dose of horse chestnut. In simple stomached animals, poisoning causes vomiting and gastrointestinal irritation. In ruminants, glycosides are converted to soluble aglycone in the rumen. This causes neurological signs.
Initially, muscle twitching, weakness, vomiting, and abdominal pain occur. In severe cases, muscle spasms are seen. Signs are usually self-limiting, but animals that progress into a coma rarely recover.
- Laboratory Diagnosis
- Hyperglycemia, glucosurea, and proteinurea are seen with severe poisoning.
- There are no specific pathologic lesions.
- No specific treatment. Laxatives may be given to facilitate the removal of ingested plant material from the intestines. Intravenous fluid therapy with calcium gluconate and dextrose may also be helpful.
Read more in the Poisonous Plants of Pennsylvania Publication