If you are a bird owner who has watched your bird have a seizure, then you know how terrifying it is. Not understanding what is going on is probably the scariest part of the entire ordeal. Let's demystify the seizure and then go over why they occur and what can be done about them.
What is a seizure? Plainly put, it is abnormal electrical activity in the brain. Normally the brain's cells, called neurons, have the job of receiving and transmitting nervous impulses from cell to cell in an orderly fashion. But when a seizure occurs, the electrical activity no longer follows the normal pathways, resulting in abnormal, random firing, which usually results in muscles twitching, which can be focal or generalized. This means either just one leg twitches, for example, or the entire body will rhythmically twitch for a short period of time.
Most often, a seizure will look frightening, but in reality, the only danger to the animal occurs if the creature falls at the beginning of the seizure, injuring itself in the fall. There is virtually no chance that a bird will swallow its tongue during a seizure, although there is a remote chance that might bite it its tongue.
That said, the other danger occurs if a seizure lasts longer than one minute, then there is a chance that the body temperature may rise to a dangerous level resulting in brain damage or possibly death.
There is a general rule that is followed by many veterinarians, the "one free seizure rule." Basically that means that we allow an animal or bird one free seizure before we begin recommending a work-up to determine the cause. However the only problem with that is that a bird may have a seizure when there is no one around to observe it, so we don't know for sure that it is the first seizure. But sometimes, there can be signs that a seizure has occurred with no one there to document it, such as many feathers out of place on the bird, too many feathers on the cage bottom or unexplained perches or toys being displaced. Sometimes, other birds may give you a clue that something has happened, as they may be acting frightened or unusually nervous.
There can be many things that can cause seizures. Seizures can be caused by a primary lesion in the brain or may be secondary (from extracranial causes). Certain infections may result in a bird developing a seizure disorder. Ear infections moving to the middle or inner ear can result in seizures. Infections from some bacteria can cause seizures, including the Chlamydophila organism, Clostridium, Salmonella, Mycobacterium, Pasteurella, Staphylococcus, Streptococcus and others. Several viral organisms can result in a bird developing seizures. The Aspergillus fungus or its toxins may result in seizures.
Metabolic causes of seizures are from low blood calcium levels, liver disease, low blood sugar or heat stress. There can be several causes of seizures from nutritional imbalances, including calcium/phosphorus/vitamin D3 issues, vitamin B1 or vitamin B6 deficiency or possibly from vitamin E/selenium imbalances. Certain toxins can result in seizures, including lead, zinc, mycotoxins (from fungus and mold), insecticides, non-stick cookware, toxic plants and salt toxicosis. Head trauma can result in seizures, as can strokes, heatstroke, emboli from yolk, parasites or clots or lastly from atherosclerosis. Certain tumors can result in seizures. Some medications can cause seizures, usually if overdosed, or if the bird is very sensitive to the medication.
Last but not least, seizures can be considered idiopathic, meaning that no other known cause can be determined for why seizures are occurring. In my experience, Red-lored Amazons and peach-faced lovebirds are the species most commonly diagnosed with idiopathic epilepsy.
Interestingly, African grey parrots, and other African parrots, can suffer from seizures related to low blood calcium. I would estimate that almost all seizuring African greys are having problems related to low blood calcium levels. This condition is usually only ever diagnosed in greys living indoors, or not exposed to any natural sunlight (not filtered through glass or plastic) or that do not have access to a full-spectrum light that emits UVB light.
When I am looking at an African grey with seizures, I always closely examine the uropygial gland as that gland produces vitamin D3 precursors that are spread on the feathers when it preens. Then the feathers and secretion must be activated by UVB light to convert the precursors to active vitamin D3. Then the bird must preen to ingest the now active vitamin D3, which is vital for normal calcium metabolism. So, if there is not enough calcium in the diet, or if the uropygial gland isn't functioning properly, or if the bird does not receive UVB light, then any one of those things can result in a bird with low blood calcium and seizures. Even if the blood calcium level tests within the normal range during veterinary evaluation, the only time the level may be low is during or right after an actual seizure.
I always recommend a beta-carotene supplement for any grey with seizures and this is why: any problems with vitamin A deficiency can result in what is called squamous metaplasia of the uropygial gland. Beta-carotene is converted to active vitamin A in the body and the rest is excreted unchanged, so unlike vitamin A, it is very safe and non-toxic. It can resolve any nutritional imbalances that might be causing the uropygial gland to not function properly.
In addition to beta-carotene, seizuring greys should also be supplemented with additional calcium. TumsTM are made from calcium carbonate and are fruit flavored so many greys will happily eat some when provided. Almonds are also a good source of calcium. Always ask your avian vet about supplements for all of your birds before instituting changes. Cuttlebone or a mineral block can also provide adequate calcium supplementation.
I think natural sunlight is beneficial to all birds but especially so for African greys and other African species. The last piece of the puzzle for seizures in greys can be corrected by allowing some outdoor time, supervised and providing shade and water and safety from predators. If that is not possible or practical, then these birds should be provided with a full-spectrum light that emits ultraviolet light in the UVB range. There are special fixtures that can be mounted safely at the correct distance from the cage to allow the birds to benefit from the ultraviolet light.
If seizures are diagnosed in any bird, a thorough physical exam, including examining the uropygial gland, should be performed. Any necessary tests should be performed and any problems diagnosed should be treated. In many cases once the cause has been identified, and treated, many seizures will cease.
In some cases, a scar in the brain may form and may cause seizures to occur even after treatment has been completed. If that happens or in cases of idiopathic epilepsy, it might be necessary to use a medication to control the seizures. While many anticonvulsants are commonly used in dog and cat medicine, we don't have solid information on dosages for birds or in some cases, what are acceptable blood levels.
Years ago, another avian vet told me about a nutritional supplement, an antioxidant called dimethylglycine or DMG that can be used to treat seizures in birds and other exotics. It works by increasing the threshold for seizures and is very safe. It is not a sedative so it doesn't make a bird sleepy or slow. If given at frequent intervals orally it may help prevent seizures from occurring or make them less severe. It is all that I use to treat seizure disorders in my avian patients.
If your bird ever suffers from a seizure lasting longer than one minute, it is a medical emergency. Find your closest veterinary clinic, call them and let them know you are coming and gently transport your bird for emergency treatment. Because overheating can be very dangerous, don't wrap your bird in a thick towel. If possible, safely cool your birds' feet with cool water or a cool wet towel.
Seizures are frightening to see, especially if you have no idea why they are happening. Once your bird has received a proper work-up from your avian vet and is being effectively treated, seizures may become a thing of the past, or if you have a bird with an on-going seizure disorder, there are safe and effective treatments that will allow your bird to experience an excellent quality of life.
Copyright © 2013 Margaret A. Wissman, D.V.M., D.A.B.V.P.
All Rights Reserved
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