Aspergillus is the fungus. Aspergillosis is the disease.
Quote From VeteranaryPartner.com:
Aspergillosis is considered one of, if not the most common, causes of respiratory disease in pet birds. It is caused by infection with a fungus of the genus Aspergillus. The species of this organism that most frequently causes respiratory disease in pet birds is Aspergillus fumigatus. This organism is found commonly in the natural environment and in fact may be found in the respiratory tract of many healthy wild and pet birds. Aspergillus makes its way into the lungs and air sacs of birds when fungal spores are inhaled from the environment. This does not normally cause a problem in fit, healthy birds, but several underlying problems and/or a massive exposure to these spores may predispose a bird to the development of aspergillosis.
http://www.veterinarypartner.com/Content.plx?P=A&C=189&A=3241&S=0
My information:
Unclean cages of nearby big birds, exposure to big birds seed waste and poop are the main causes of Aspergillosis in canaries. Keep the Canary cages away from the big birds' cages if you have big birds. Keep them 5 or 10 feet apart or across the room if you have space. The waste seeds and poop from the big birds can release spores of aspergillus fungus which can and will slowly kill your canaries. Clean all bird cages twice a week. Do not use wood chips, corn cob chips ect. Keep bulk organic material out of all cages. Again, this is because of the aspergillus risk. Don't worry about all the minute details. Mostly just get the waste out and do not use organic shredded material at the bottom. Keep your canary cage sitting up on a chest and away from windows and drafts. Up on a chest helps keep the air fresher. Drafts and pathogenic air usually travel low in the room. Keep the cage up against a wall. This makes the canary feel more secure and also helps keep away drafts. Put a mirror behind the cage. They love to see themselves in a mirror. Hang some canary toys, one with a little mirror. Go to Lowe's or Home Depot and get 2 mil thick plastic like they use for painting drop cloth and cut it to the size of the bottom of the cages. If you have big birds do not fly them in place. This will stir up the aspergillus spores. If your Canary quits singing, and fluffs up, watch out! It could be chronic Aspergillosis setting in! Without intervention, the Canary will go into acute Aspergillosis someday soon and be dead in 5 days. A shop vac is useful for cleaning the big birds' cages but keep the filter clean and empty the contents often.
Control of Aspergillus is my Golden Rule Number One of my Four Golden Rules of Canary Care.
Now let us explore some of the many Aspergillus links on the internet. Let's start with the tragic story of "Baby". Because of this story, it becomes clear not to feed peanuts in the shell to big birds.
The story of "Baby" and more great information on Aspergillosis are at this link from AvianWeb.
The main thing to look out for is a change in voice or the absence of sound. In canaries, look out for and absence of singing, an absence of sound, weight loss, diarrhea, and of course, the fluffing up signal of stress.
more content coming soon