Ask any horsey person what plant is most dangerous to horses and we bet 9/10 will reply “Ragwort”. But is it so bad that it can kill a horse? There are a lot of myths about this poisonous plant – let’s bust a few here!
What is ragwort?
From May to October, you will see ragwort flowering in tall bunches. It’s a really common weed that grows in the UK around waste ground, roadsides and often, in poorly managed horse pasture. It flourishes when other plant growth is sparse, so if there’s not a lot of grass around, there’s a chance it will get eaten by horses despite its bitter taste when it’s alive.
What is the problem with ragwort?
When it’s cut or wilted (during hay or haylage making) ragwort loses its bitter taste but none of its toxicity. In fact. it becomes far more palatable and harder for the horse owner to spot, thus posing more of a danger.
Here’s the scientific bit…
Ragwort contains the toxic compounds pyrrolizidine alkaloids. If any part of the ragwort plant (either growing or in its dried form) is consumed by the horse these alkaloids will be absorbed through the gut wall into the bloodstream and then passed through the liver. Unfortunately, the liver is incapable of removing the alkaloids, or rendering them harmless, and as a result the liver cells (hepatocytes) are damaged. Once these cells are damaged, it’s very difficult for them to regenerate and slowly they die, replaced with fibrous tissue. Once there are not enough healthy liver cells left to enable the liver to function properly – the liver fails.
Liver failure = death
The effects of ragwort poisoning are cumulative – consuming small amounts over a long period of time is just as dangerous as consuming a large amount in a single session, and often horses and ponies who have eaten ragwort may not show signs until significant liver damage has been done.
What are the signs of ragwort poisoning?
- colic or abdominal pain
- weight loss
- and, some rather strange behaviours caused by the effect of chemicals on the brain including pressing the head against the wall, continuous circling or aimless walking and loss of coordination.
Is there any good news?
Well, yes – and it’s down to you and some hard work to sort it out! The key to success is prevention. In other words, get rid of all ragwort on your grazing land. You must pull out the roots from the ground to prevent it from re-growing, and you are advised to wear gloves and even a face mask to prevent you absorbing the toxins through your own skin or inhaling the pollen. Ragwort must also be disposed of carefully – the best way is to let it wilt and burn it, keeping it in sealed plastic bags during the wilting process to prevent the seeds spreading.
So, in summary – sadly, yes ragwort really can kill your horse but it’s not all doom and gloom – look out for the flowers now whilst they are blooming, tog up and get rid of the plants for good.
If you’d like more info on dealing with ragwort, check out the BHS website www.bhs.org where they have some excellent advice on a toolkit to help you deal with this pesky plant!