Vetchling (Lathyrus spp.)
Lathyrus spp.
Horse
Severe
Any suspected ingestion is an immediate veterinary emergency. Generally chronic intoxication, due to the ingestion of large quantities over several weeks/months (often via forage).
Equio informs, it does not diagnose. When in doubt, call your vet.
What to do now
- Antidote
- No specific antidote. Intensive symptomatic and supportive treatment.
- Time to signs
- Several weeks to several months of chronic ingestion
- Prognosis
- Grave. Once nerves are damaged (roaring, paralysis), lesions are often irreversible and the horse may remain permanently disabled.
- Immediately stop the source of intoxication.
- Contact a veterinarian without delay.
- Manage nervous symptoms.
Its ID card
- Height
- 0.3 m – 1.5 m
- Flowering
- June to September (depending on region and species).
- Toxic parts
- The seeds are the most toxic part, followed by the stems and leaves.
- Toxin
- Neurotoxic amino acids (ODAP: beta-N-oxalyl-L-alpha,beta-diaminopropionic acid)
- Habitat
- Pastures, wastelands, woodland edges, cultivated fields (sometimes as a replacement forage in the south).
- Soil indicator
- Dry, poor, arid soils.
- Regions
- Southern Europe, Mediterranean Basin, Central Europe
- In hay
- Yes — stays toxic once dried
- Palatability
- Quite palatable (protein-rich legume), often readily grazed with grass.
When the risk rises
Summer (pod formation) and year-round in hay.
Spotting it in the field
Vetch (which also has its own toxicity), Sweet pea. — smell : odorless or a mild herbaceous scent.
- Herbaceous plant, often climbing or trailing with tendrils.
- Flowers characteristic of legumes (like sweet peas), pink, red, or yellow.
- Flat pods containing seeds.
Signs to watch for
Chronic (cumulative) toxicity
Dose : Significant quantity of seeds or contaminated forage over a prolonged period.
- Progressive weakness and staggering of the hindquarters
- Motor paralysis (horse struggles to stand up)
- Roaring (harsh noise on inspiration due to laryngeal paralysis)
- Muscle stiffness
- Apathy and tremors
Who is affected
Other species : Toxic to humans (historical human lathyrism during famines) and ruminants.
In pregnant mares : neurotoxic risk to the fetus.
Getting rid of it
Method : Pull plants before seed formation, ideally wearing gloves. Burn uprooted parts to prevent dissemination.
- Inspect pastures and remove vetch plants before grazing or haymaking.
- Avoid sowing forage mixes containing vetches for horses.
- Never feed hay or concentrates potentially contaminated with vetch seeds.
Frequently asked questions
Can Equio identify Vetchling (Lathyrus spp.) from a photo?
It can help organize visual clues, but plant identification must remain cautious when horse health is at stake.
Is Vetchling (Lathyrus spp.) dangerous in hay?
This entry flags hay vigilance. Isolate suspicious forage and ask for professional advice if exposure is possible.
This page is informational. If ingestion is likely, if signs appear, or if the horse is fragile, contact a veterinarian immediately.