Poisoning

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POISONS

that affect horses

RAGWORT

The most common of the poisonous plants is the Ragwort which is commonplace throughout the countryside. The toxin is an alkaloid and causes damage to the liver.

If a horse has eaten Ragwort some of the common symptoms are colic, the look of depression and listlessness.

A chronic form of the poisoning is a result of sustained ingestion of the ragwort over the period of months, where the horse will show odd behavioural patterns such as persistent yawning, sleepiness and wandering about aimlessly.

The more extreme cases there will be signs of a neurological disturbance, such as pushing the head against objects circling the head similarly to weaving, in extreme cases the horse may die within days.

The diagnosis of Ragwort poisoning can be established by the use of a blood test , However all the tests such as liver biopsy liver function tests as well as ultrasound can be used and may show of the diseases of the liver and pathology.

There is not at the moment a viable treatment for ragwort poisoning and the prospects are extremely poor.

TREES and SHRUBS

All parts of the Yew tree are highly toxic to horses. The horse is also extremely sensitive to Laburnum especially the flowers and seeds.

T he leave s of the Privet are also toxic. T he Rhododendron also presents a risk to horses.

Cherry tree and Laurel ingestion will cause the release of cyanide, veterinary advice must be sought.

The seeds and bark of the false Acacia tree and the Box, contain toxins that will cause colic and diarrhoea .

Unripe Acorns from the Oak tree and Beechmast are also poisonous to horses. Acorns can cause colic, diarrhoea or constipation. Some horses develop a liking for Acorns and such horses should be kept away from Oak trees. Beech nuts will cause colic, tremors, staggering and excitability. The same toxins can also be found in bracken.

FOXGLOVES

The Foxglove contains a toxin that has an adverse affect on the horse's heart and will cause severe depression and colic. This is a fast acting poison and the horse may well be found dead.

FUNGAL

Fungal toxins are normally associated with poor quality or mouldy hay which causes respiratory and gut related problems.

SNAKES

The main venomous snake in Britain is the Adder and although horses are susceptible to the venom, a death is very rare. An anti venom serum as well as a broad spectrum antibiotic and tetanus anti serum should be administered.

FOOD POISONING

Botulism is a known contagious disease which is caused by the release of toxins from the botulinum bacteria which is commonly ingested from contaminated feeds. Symptoms normally start as gut related but then rapidly progress to neurological.

MEDICATION POISONING

It has been found that some antibiotics can cause toxicity by altering the normal growth of gut bacteria , hence allowing the proliferation of pathogens.

Phenylbutazone given correctly will be unlikely to cause problems however overdosing will cause toxicity . Dosage rates should be discussed with your vet prior to administration.

If your own confidence level is not at its best then an alternative is to seek further help.

Best Wishes.

Bob Howarth

Be Safe

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Author of Poisoning  Bob Howarth, resides in the United Kingdom. He is a horse owner, trainer and writer.  For more information go to www.horserealm.com or e-mail postmaster@horserealm.com