Poisonous Plants
Acorn
Acorn poisoning is rare.
Acorns contain tannic acid, which when eaten in sufficient quantities causes liver and kidney damage.
Symptoms can include colic, diarrhoea and blood in toppings.
other symptoms include, acorn husks in droppings, mouth ulcers, depression, dehydration, lethargy, constipation.
Black nightshade
Most horses will not eat Black nightshade, unless no other food source is present.
Symptoms include: diarrhoea, loss of appetite, loss of muscular coordination, sudden depression and dilated pupils.
Often consumed as dried matter found with in baled hay.
Estimated 1-10lbs ingested can be fatal to horses.
yew
Common in gardens, the fallen leaves and berries are lethal to your horses as a fresh horse.
0.5 KG can be fatal
ragwort (flower)
Takes 2 years to fully grow and flower, from rosette of leaves in 1st year, to bright flower on a woody stem 30-100cm in its second year.
Each plant produces thousands of seeds, easy and widely dispersed by the wind.
ragwort
Rarely eaten whilst growing, however when wilting or dead becomes more palatable for horses.
Contains toxins resulting in liver failure or even death.
Eating 1-5 KG during a horses lifetime could be fatal.
golden rod
All parts are poisonous. A horse needs to only eat 1-1.5% of their body weight to become poisoned.
Symptoms can include: hind leg weakness, posterior paralysis, knocking at fetlocks, respiratory paralysis, severe muscle tremors and even death.
horse tail
None flowering, fern like, spore producing pant.
Toxiticity produced by an enzyme Thaiminase.
Thiaminase destroys Thiamine,, an important B vitamin required for correct brain function.
Poisoning symptoms develop slowly in horses. Symptoms begin with weight loss, a dull/ scruffy appearance without a loss of appetite.
Without treatment symptoms will worsen to balance issues, loss of control of muscle movements and death in 1-2 weeks.
woody nightshade (berry)
Toxicity is highest in green berries, followed by red and black berries, leaves, stems and root.
hemlock
Toxins found in hemlock directly affect the horses nervous system, neuromuscular junction and brain.
Toxicity levels vary depending upon the stage of growth.
Signs of poisoning will develop 1-2 hour post ingestion.
A lethal dose of poison hemlock rabies from 0.2-0.8% of the horses body weight.
A few of the symptoms include: paralysis, colic like symptoms, nervousness, seizures, rapid heart rate
deadly nightshade
Despite its name, not usually fatal to horses, can cause unconsciousness, convulsions and dilation of the pupils
Flowers are often 5 lobed, white or purple flowers, forming fleshly green berries that turn yellow or black once matured.
woody nightshade
Flowers are often 5 lobed, white or purple in colour. Forming fleshy green berries that turn yellow upon maturity.
Not normally eaten by horses, but if ingested same symptoms as described for Black nightshade.
privet
Green leathery leaves, small funnel shaped white flowers (June - July) which ripen into dropping clusters of blue/ black wax coated berries, ripening in September and usually lasting the winter.
Privet disrupts the horses gastrointestinal system and can cause colic and renal damage.
Some symptoms include: colic, diarrhoea, renal damage and convulsions.