The subject of bacterial contamination of food and water for caged birds is rather controversial.
Many apparently healthy caged birds harbor potentially harmful bacteria within their intestinal tracts. These organisms can create illness during periods of stress (short- or long-standing) for your bird. Many veterinarians agree that Gram-negative bacteria (coliform type) can contaminate seeds, seed mixes, unwashed fruits and vegetables, and even tap water. Consequently, it may be advisable to bake or microwave seeds and seed mixes (spread seeds to a depth of 1 inch in a Pyrex dish and bake at 350 F for 10 minutes, stirring once, or microwave on high setting for 5 minutes). This seems to eliminate these potentially harmful bacteria and other food related diseases without compromising the nutritional value of the seed.
The skins of all fruits and vegetables should be thoroughly washed before being offered to your bird. One study clearly demonstrated that colony counts of potentially harmful bacteria in tap water samples could be greatly reduced by allowing the tap to run for at least 3 minutes before the water cup was filled. Offering bottled water is probably an acceptable alternative, though bottled water dispensers occasionally harbor disease-carrying bacteria. The spigot should be opened a few seconds and water allowed to run before filling the water container.
The recommendations mentioned above should help you to offer the correct foods, but there is no guarantee that your pet bird will accept and consume any or all of them.
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