What never to feed: toxic plants and contaminants

Some plants kill a horse within hours; some feeds that look wholesome make him ill because they are mouldy or soiled. Recognising them is part of your job as a rider.

In the exam programme

Recognise the main things never to feed: poisonous plants and feed contaminants.Common module B

Left to himself, a horse avoids most toxic plants, which are often bitter. He gets caught out when he is hungry — an overgrazed field, drought, late autumn — when the plant is dried and mixed into the hay, or when someone throws him hedge clippings. The rule is simple: he eats only what you know is safe.

Yew

Flat needles in two rows, red berries.

Oleander

Long narrow leaves in threes, five-petalled flowers.

Thuja

Flattened, fan-shaped sprays covered in scales.

Box

Small, glossy oval leaves in pairs.

False acacia

Leaves of oval leaflets, paired thorns, flat pods.

Sycamore

Five-lobed leaf, winged seeds in pairs.

Ragwort

Ragged, deeply cut leaves; flat heads of yellow flowers.

Meadow saffron

Mauve flowers without leaves, in autumn, in damp meadows.

Fig. 4.6Some common toxic plants

Plant	Where it grows	Why it is dangerous
Yew	Hedges, parks, churchyards	Deadly in tiny amounts, often within hours, by stopping the heart
Oleander	Gardens, roadsides, especially in the south of France	Toxic to the heart, fresh or dried
Thuja, box, cherry laurel	Garden hedges	Dangerous above all when clippings are fed
False acacia (robinia)	Tracksides, woodland edges, hedges	Bark, seeds and leaves are toxic: serious digestive trouble
Sycamore	Trees along field boundaries	Its winged seeds, in autumn, and its seedlings, in spring, cause atypical myopathy, a muscle disease that is often fatal
Ragwort	Overgrazed fields, roadsides	Slowly destroys the liver; stays toxic when dried in hay
Autumn crocus	Damp meadows, mauve flowers in autumn	Highly toxic, in hay too
Bracken, horsetail	Woodland edges, damp fields	Toxic above all when mixed into hay and eaten over weeks

Toxic plants to know

Feed contaminants

A feed can become dangerous without being so to begin with: it has been contaminated. These are called feed contaminants.

Mould: hay or grain that smells musty, feels warm, gives off a white dust or shows patches. Fungi produce toxins and spores in it that attack the gut and the lungs.
Dust and soil: very dusty hay irritates the airways; feeding straight off sandy ground makes the horse swallow sand.
Dead small animals: a rodent or bird caught up in a bale of hay or haylage can pass on botulism, a poisoning that is often fatal.
Feed for other species: some poultry or rabbit feeds contain additives that are deadly to horses.
Chemicals: rat poison, fertiliser, weedkiller, old lead paint, treated timber that the horse licks or chews.

Good ideas that are not

Grass clippings: piled up, they ferment within hours and cause serious colic.
Fresh or soft bread and leftovers: they form a ball that can block the gullet (choke).
Too many treats or too much grain, and any sudden change of diet: the gut bacteria do not have time to adapt.

Safety

If you see a horse eating a plant you do not know, or you find yew or laurel branches in a field, take him out and tell someone in charge at once, even if he looks fine. The signs of poisoning may only show several hours later.

Common mistake

Giving the horses the hedge clippings “because it’s green”. Thuja, yew, box and laurels are precisely the most toxic hedge plants.

Ekidemy

The Galops^®, from the first step to Galop 7