Quantity
A single raw green potato probably won't kill a full-sized horse, but it can cause significant gastrointestinal distress. Multiple potatoes, or regular access to potato waste, can cause serious toxicity. Green potatoes and sprouts are the most concentrated and dangerous.
Notes
The most common exposure scenario is garden waste. People clean out the pantry, find green or sprouted potatoes, and toss them into a compost heap near a paddock. Horses are curious and will eat almost anything offered or found. Green potatoes and potato sprouts have the highest solanine concentrations. Potato vines and leaves from the garden are equally toxic. Cooked potato in very small amounts is less dangerous because cooking reduces (but doesn't eliminate) solanine.
Negative Signs
* Colic signs — pawing, rolling, sweating, looking at flanks
* Diarrhea or constipation
* Loss of appetite and drooling
* Dilated pupils
* Muscle tremors and weakness
* Staggering and loss of coordination
* Slow heart rate in severe cases
FAQ
Q: My horse ate a potato that someone dropped. How worried should I be?
A: If it was a regular, non-green potato, your horse will probably be fine — monitor for colic signs over the next 12-24 hours. If it was green-skinned or sprouted, call your vet. Either way, make sure no one dumps potato scraps near the paddock again.
Alternatives
If you want to give your horse a root vegetable treat, carrots and turnips are safe and well-loved choices. Keep potato waste away from paddocks entirely.
Risks & Disclaimer
If your horse ate raw potatoes, especially green ones, call your vet. Solanine is not destroyed by the horse's digestive process, and because horses can't vomit, the toxin will be absorbed as it passes through the entire digestive tract. Monitor closely for colic signs.
