Poisonous plants for horses in autumn

Numerous poisonous plants in the UK can be detrimental to our horse’s health in Autumn. As we focus on adding vitamins, minerals, and supplements into our horses’ diets to aid their health, it can be difficult to know what should be eliminated from their diets. What plants should be on our radar, and what do they look like? As the new season begins and we start preparing our paddocks for autumn, we have compiled a list of common autumn poisonous horse plants.

Take this list of poisonous plants with you as you complete your pasture management routine this autumn. Identify, be alert to symptoms, and implement prevention measures to prevent nasty surprises and protect horse health!

Sycamore

It was once though that sycamore was not toxic to horses. However, in recent years the plant has be found to trigger the often-fatal muscle condition, Atypical Myopathy (AM).

AM is caused by the ingested sycamore seeds, otherwise known as ‘helicopter seeds’. As the leaves and seeds of sycamore begin to drop in autumn, the spread of these tiny capsules of poison becomes more and more prevalent.

AM causes muscle damage, particularly affecting the muscles which the horse uses to stand up, breathe, and allow the heart muscle to beat. With a 10-25% chance of survival, it is important to keep an eye out for the presence of the seeds in paddocks, plus clinical signs as keeping control of the seeds is almost impossible.

Clinical signs your horse may be suffering from AM include;

• Lethargy
• High heart rate
• Stiffness
• Dark urine
• Difficulty standing/ keeping their head up
• Trembling

Prevention of sycamore seed and leaf ingestion is key to preventing the fatal condition, AM. As you prepare your paddocks for autumn, move away from sycamore trees to prevent ingestion and ensure horses have enough supplementary feed to minimise the risk of foraging for alternative feed. Additionally, ensure to remove any seeds and leaves that may blow into your paddocks the best that you can, and remove seedlings that will begin to grow in spring.

Bracken

Bracken is normally found on moors and meadows, so owners with a horse grazing on these types of terrain should be more aware of the plant. Although horse tend to avoid eating the plants, some horses do develop a taste for it or opt to eat it when grazing is poor.

The good news is that it is only poisonous in large quantities, so your horse would have to eat it over a sustained period of time to receive any ill effects. However, this does not mean the plant shouldn’t be something you can leave safely in your paddocks. Bracken poisoning affects the horse’s nervous system, affecting the brain and everything it controls. This can result in symptoms such as;

• Muscles spasms
• Lack of balance
• Blindness
• Disorientation

If caught early enough, a vet will be able to treat bracken poisoning with thiamine supplements, although owners should go the extra-mile to prevent ingestion of this deadly plant. Prepare for autumn by removing bracken and optimising your pasture management to maintain good grazing through wintershould reduce any consumption of bracken, by your horse.

Oak

Oak trees, although grand and majestic, are the cause of serve organ damage and even death when parts of the tree are ingested by horses.

Acorns, which fall from oak trees, have been known to become an addiction for some horses. Although, containing tannic and gallic acid, ingestion of acorns can cause severe damage and erosion to the gastrointestinal system and kidneys of the horse. However, it is not just acorns form the oak tree which are a threat to horse health. The leaves, stems, bark and twigs are also toxic.

Due to oak consumption affecting the digestive system and organs related to their urinary systems, it is important to keep an eye on anything related, from your horse’s appetite to the normality of their faeces and urine. Symptoms of oak poisoning may include;

• Constipation
• Weight loss
• Blood in urine
• Colic

Although, oak poising is difficult to diagnose. Prevention is better than cure for any poisonous plant disorder, so autumn paddock prep is essential! Fence off oak tree if you cannot move paddocks and make sure your pasture management is tip-top, ensuring there is optimal grazing for your horse to eat. Pick up any oak leaves and branches, as well as acorns that may blow into your field.