The avocado – once considered exotic – is now a diet staple in Australia. Like many human foods, avocados often sneak into the food bowls of pets. For most animals, including dogs and cats, small amounts of avocado have little impact. For birds, it’s a different story.
Avocados (Persea americana) contain a toxin called persin and fed to birds, even a small amount can be fatal. Canaries, parakeets, cockatiels and other parrots are known to be susceptible to the toxin. Other animal species highly susceptible to persin include rabbits, horses and ruminants.
All parts of the avocado – leaves, fruit, seeds and bark – are poisonous. Prognosis for affected birds and other susceptible species is poor and it’s safest to avoid feeding any part of the avocado tree and its fruits to pets and domestic animals.
Persin affects most organs and the toxicity can cause sudden death. Affected birds are unable to perch and respiratory distress develops, with accumulation of fluid around the heart and lungs. Liver and kidney failure precede death. Similar respiratory symptoms are seen in other species vulnerable to the effects of the toxin.
Signs of illness in dogs and cats can include a mild stomach upset, with vomiting and diarrhoea. In dogs, an inadvertent risk is oesophageal or intestinal obstruction if the large avocado seed is swallowed.