Can dogs eat avocado?
Risky. Mostly not for the reason you have heard. Merck describes dogs as relatively resistant to persin; the real hazard is the pit.
How much is dangerous?
Merck publishes dose thresholds for goats and budgerigars but none for dogs, because dogs are not the susceptible species. Anyone quoting a canine toxic dose for avocado is quoting a number that does not exist.
Why it does harm
Persin is the toxic principle in avocado and it seriously affects birds, rabbits, horses and ruminants. Merck states that dogs seem relatively resistant by comparison, citing a single case report of two dogs with myocardial damage. The documented canine risk is foreign body obstruction from swallowing an intact pit, plus digestive upset from the fat.
What to look for
- Vomiting or diarrhea from the fat content
- If a pit is swallowed: repeated vomiting, loss of appetite, straining, and abdominal pain
What to do
- If the pit was swallowed, call your vet. That is an obstruction risk, not a poisoning, and it is the part that needs attention.
- A lick of guacamole is a different question — the onion and garlic in it matter more than the avocado.