When walking through the woods with your dog you may come across a scattering of acorns underneath an oak tree, but are acorns bad for dogs, can they be poisonous and what should you do if your dog eats them?
What is an acorn?
Did you know that an acorn is actually a fruit? Its hard and woody outer shell protects a single seed inside it that can grow into an oak tree. Acorns are green when they first grow, but become brown as they ripen. Towards the end of summer, or around early autumn, these hard fruits fully mature and fall to the ground, ready to grow into a new tree…or be eaten by your dog!
Are acorns harmful to dogs?
Yes, they can be. Acorns contain tannins, which can be poisonous to dogs. These toxins can cause your dog to be sick or may upset their stomach. If enough tannins are eaten it can produce more serious effects, such as kidney or liver damage.
How poisonous are acorns to dogs?
The tannins in acorns have a nasty bitter taste, which may put many dogs off. Eating small amounts of tannins may give your dog a stomach upset, but consuming larger amounts can make them very unwell.
How much does my dog need to eat to make them ill?
The amount of tannins in each acorn is different, so it’s impossible to know the number of acorns your dog would need to eat to make them unwell. The concentration of tannins in an acorn changes as it ripens. Unripe green acorns contain higher amounts of tannins, whereas brown acorns contain less, making them less poisonous. The concentration of tannins varies from tree to tree and year to year and is dependent on a number of different factors. How your dog is affected by tannins will also depend on how big your dog is, how much they’ve eaten, when they last ate, how much they chew up the acorn and if they have any other health issues.
What happens if my dog eats an acorn?
After eating an acorn, your dog might become unwell quite quickly, or it may take a day for effects to show.
Symptoms of acorn poisoning include:
Poisoning is not the only risk from acorns. Your dog could choke on them or they could block their stomach or gut.
If your dog eats acorns then contact your vet for advice.
Symptoms of acorn poisoning include:
- Being sick – may contain blood
- An upset stomach – may contain blood
- Stomach pain
- Being tired
- Shaking
- Red itchy skin
- Kidney damage (signs of this can include a change in how much your dog drinks or how often they wee)
- Liver damage (signs of this can include similar effects to those listed above, as well as confusion, not walking in a straight line or a yellowing of the skin, gums or eyes)
Poisoning is not the only risk from acorns. Your dog could choke on them or they could block their stomach or gut.
If your dog eats acorns then contact your vet for advice.
Did you know that dogs don’t have ‘symptoms’?
Technically, the definition of a symptom is a clinical effect that’s been described by the patient. Since dogs can’t describe how they're feeling they actually have ‘clinical effects’ rather than ‘symptoms’. In some of our articles we use ‘symptoms’ because it’s a well understood term and is commonly used by dog owners. It may not be the correct use of the word, but we aim to produce information that’s accessible to all and can be easily found by owners.
What other parts of an oak tree are poisonous to dogs?
All parts of an oak tree are poisonous and could make your dog ill. Tannins are found in the bark, wood, leaves, buds and fruits (acorns).
How do I stop my dog from eating acorns?
If your dog likes to eat acorns you could keep them on a lead or use a basket muzzle when going for autumn walks, especially in areas where you know there are oak trees. When walking near oak trees, bring along a ball or a chew toy to help keep their mouths occupied.
When should I contact my vet?
If your dog has eaten acorns then you should contact your vet for advice. Your vet will be able to advise you if your dog needs to be seen by them and what treatment will be needed. Never try to make your dog sick as this can be dangerous and can cause other problems.
Think your dog may be affected?
If you're worried about your dog's health, always contact your vet immediately!
We are not a veterinary organisation and so we can't give veterinary advice, but if you're worried about any of the issues raised in this article, please contact your local vet practice for further information
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If you're looking for a vet practice near you, why not visit the Royal College of Veterinary Surgeons' Find a vet page.