|by Donna Muscarella Ph.D
I teach exotic avian husbandry at the Cornell Veterinary College
and talk about avocado toxicity in my course.
Avocados are definitely toxic to parrots. They contain a cardiac glycoside ("persin") that leads to rapid cardiac arrest and death. There are studies that show that some species, including African Greys and cockatiels, are very susceptible to the toxin. I'm sure there are other species that are also susceptible
Even though many animal species are sensitive to the toxin, people are not. In fact, avocados are quite nutritious and contain a good dose of "healthy" monosaturated fats. So, I do enjoy eating them..but am very careful to clean the kitchen area and utensils etc. so that my birds are not accidentally exposed.
I too have heard of parrots eating avocado with no ill effects. (In particular, Amazon parrots who frequent someone's
backyard in Florida.) It is possible that some species are more resistant than others. If this was the case, there would be genetically based differences in metabolism of the toxin. This is possible and does explain differences in sensitivity to some toxins in animals an in people. Whether this is true for parrots and avocados is not certain. It is also possible that some avocados or parts of avocados are more toxic than others. Toxicity may vary with ripeness or with the part of the avocado eaten. Perhaps in the wild, parrots learn from others which ones to eat - or what parts are safe. It is known that macaws in the wild learn what to eat from other macaws - they even eat clay which is believed to neutralize toxins found in the diet. Again, this is a possibility, but nobody knows for sure.
However, because avocados are so highly toxic to at least some species - and because there is no way to know this for a
particular bird ahead of time- it is best to avoid feeding them.
Donna Muscarella Ph.D
Laboratory of Molecular Toxicology
College of Veterinary Medicine
Ithaca, NY 14853