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Autumn Hazards – Why conkers are bad

Conkers and Autumn go together. They conjure up the essence of that ‘back to school’ feeling, perhaps because their gorgeous glossy mahogany colour echoes the shiny leather of new shoes.

When we see an abundant scattering of conkers under a horse chestnut tree, it’s hard to resist the temptation to pick a few up and put them in our pocket for later. Quite what we’ll use them for is another thing.

But although humans may be irresistibly drawn to conkers, you might be surprised to hear that they can be toxic for our four-pawed friends.

What is a conker, exactly?

Conkers are the seeds of the horse chestnut tree. They’re contained in a bright green prickly covering that has to be broken open to reveal the seed inside.

Conker facts

  • There’s no proof that conkers repel spiders.
  • However, the triterpenoid saponin in conkers could deter moths.
  • Horse chestnut extract is said to improve circulation.
  • Deer and wild boar can safely eat conkers.
  • Despite the name of the tree, the seed of the horse chestnut is toxic to horses.

When do conkers appear?

Conkers usually start to fall from the trees in late September. The fact that the World Conker Championships take place on 11 October in Northamptonshire this year suggests that conker aficionados expect to be able to collect some prize specimens in early October.

This means that September to early October is the key time to expect to see conkers spreading out under horse chestnut trees this Autumn.

Toxic to eat for dogs

Eating conkers can be hazardous for dogs. This is due to a chemical component in the seed called aesculin, which is also present in the leaves and bark of horse chestnut trees. Conkers are extremely bitter, which generally deters dogs from eating them. However, every Autumn, sadly, some dogs are poisoned after eating conkers.

If your dog has eaten conkers, you might see the signs within an hour to six hours. Symptoms of horse chestnut poisoning include:

  • Vomiting
  • Diarrhoea
  • Drooling
  • Abdominal pain
  • Disorientation
  • Excessive thirst
  • Loss of appetite
  • Seizures
  • Muscle tremors

A high dose of aesculin – caused by eating several conkers – could affect the central nervous system and might even be fatal for your dog.

How to treat conker poisoning

If you suspect that your dog has eaten conkers, you should take them to a vet straight away.

Your vet is likely to give your dog a treatment that will induce vomiting and might wash out your dog’s stomach too. Your pup might also need an intravenous drip.

If there’s an internal blockage caused by conkers, surgery may be necessary.

Stay alert

Luckily, with the right treatment, most dogs recover from horse chestnut poisoning.

In the meantime, while you’re out and about this Autumn, steer clear of the spreading chestnut tree, tell your kids that conkers are poisonous for dogs, and carry a toy to distract your pup from those beguiling mahogany brown seeds.