Giardia is a one-celled protozoal organism that is commonly found in pet and aviary birds. It lives in the small intestines (usually the duodenum) and is shed sporadically in the droppings. It may cause diarrhea, malnutrition and malabsorption in affected animals. In some birds, especially cockatiels, it may induce pruritis (itching), causing a bird to scream and pull feathers or dig at the skin with the beak. The skin of birds infested with giardia may appear dry and flaky. Most often, the underside of the wings, the insides of the thighs and perhaps the chest are plucked.
Giardia is quite common in cockatiels, lovebirds and budgies, however, it can be found in most species of birds, including Amazons, macaws, pionus, Eclectus, lories, parrotlets, parakeets, African grey parrots, Poicephalus and cockatoos. It is also found in canaries, finches, doves and pigeons. Groundbirds are commonly infested. In addition to causing diarrhea, malnutrition, itching, feather picking and weight loss, it may also cause mortality of baby birds in the nest. Often, the babies will be very thin, have poor feathering and will cry excessively to be fed. Many will die before fledging. The droppings may be malodorous. Adults and babies may show staining of fecal material around the vent.
The organism is difficult to diagnose for several reasons. Giardia is not shed in every dropping. It is a very fragile organism in one form, and may disintegrate before it can be diagnosed. Regular fecal parasite exams, performed in a vet's clinic or by a professional lab, may miss this organism because of its fragility. A new procedure has greatly increased the chance of diagnosing giardia in birds. This involves preserving the feces (and giardia cysts) in 5% formalin (NOT the usual 10% used to preserve normal tissues). The preserved feces are then sent to a special lab that only studies parasites, and a different type of microscope, called a phase contrast scope, is used to diagnose giardia. By your veterinarian going the extra distance, this elusive parasite has been diagnosed in your bird.
You may be surprised that your bird is being diagnosed now with giardia, as it may have been examined by a veterinarian previously, and it may even have had fecal parasite exams performed in the past. A solitary pet bird may harbor giardia for long periods of time before showing signs of illness. New methods of testing have greatly improved the chance of a positive diagnosis.
In the past, treatment was usually administered by using a drug called Flagyl (metronidazole.) This drug only comes in an injectable form, which is not good for birds, and in a tablet that is so bitter that no matter what it is mixed with, it is very unpalatable. Flagyl only is effective in about 40% of giardia-positive birds. Another drug, fenbendazole (Panacur) may work well to clear many birds, however, it can cause feather deformities and it may cause liver problems in some birds. Other drugs have been tried, with varying success. Another drug that may be somewhat effective is Humatin (paromomycin). This drug must be administered orally by syringe. Dr. Wissman usually chooses to use a drug that she imports from Germany, that is not available in the U.S. to treat giardia. It is called dimetridazole. It is a drug that can be easily administered in the drinking water. Properly administered, it is safe and effective in clearing a high percentage of birds harboring giardia.
It is probably a good idea to treat all birds directly exposed to an infested bird or its droppings. Testing prior to treatment will identify the degree of infestation of those birds. Retreatment may be necessary periodically. Retesting is an important part of managing giardia, and follow-up examinations are necessary. Be sure to follow your avian veterinarian's advice.
It must be noted that some birds will never be completely cured of giardia, and it may occasionally flare up. Providing your bird with a secure environment, feeding a balanced, nutritious diet and using a water bottle will help prevent reoccurrence of problems. Excellent sanitation and husbandry practices must be employed, as well. Exposure to droppings should be minimized. A grate at the bottom of the cage should be used. Spraying the grate with non-stick cooking spray (PAM) will allow droppings to slide off the grate and into the bottom of the cage.
Water bottles may be purchased at most pet stores and feed stores, and are useful in preventing contamination of drinking water with fecal material. Water bottles also prevent high levels of bacteria from growing in water bowls. One of the best preventative medical things that you can do for you bird is to buy it a water bottle today and begin using it. Birds are so smart that almost all birds will discover how to use a water bottle immediately after it is placed in the cage. Plastic bottles may be used for the smaller birds, but for large birds, a glass bottle with a stainless steel drinking tube, which is almost indestructible, should be purchased. The tube should be checked daily to ensure that the system is not plugged up and is delivering water. Some birds will stuff a seed, piece of toy or shell into the tube, effectively plugging it up. Other birds may learn how to stick a toenail into the tube to take a shower under it, thus emptying the whole bottle in short order. If your bird loves to take a bath, provide a large bowl of water several times per week for this activity, or try taking it in the shower with you.
Your bird's giardia should not be contagious to humans or other types of pets in the home. It is contagious between birds, however. It is not thought to be transmitted through tap water (unless it is contaminated with bird droppings!) The giardia that infests humans is a separate organism, according to latest research, and is not contagious to birds.
Giardiasis is a very frustrating disease, as it may be difficult to cure, but can be controlled, by following your avian veterinarian's advice, giving medication as directed and practicing excellent hygiene. Don't forget how important a water bottle is to prevent reinfestation. Feather picking associated with giardia may resolve after treatment, however, it may return from time to time. This can be very aggravating, and other methods may need to be employed to control feather picking, in addition to treating the giardia itself.
Copyright © 2006 Margaret A. Wissman, D.V.M., D.A.B.V.P.
All Rights Reserved
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