Aspergilla In Canaries

Contributing author Enrique Moreno

Aspergillum is also known as Mitotic Pneumonia as well as Breeders Pneumonia. The fungus known as Aspergullusfumigatus though its cousin Aspergillum Niger on occasion causes it causes it.

Aspergilla is a very huge economic devastator of chicken farms and is frequently also found as the culprit in respiratory sickness in flock birds as in wild and aviary bred birds too.

In the early 1800s mold was discovered growing in the air sacs of waterfowl. The first time it was described as the cause of lesions in the air sacs was in 1842 in a Royal Chaffinch (Fringilla montifringilla). Not until 1912 was the aspergilla was written about by De Jong in canaries in which he noticed these manifested as tiny whitish yellow crusted bumps on the tongue, upper and lower mouth membranes and on the upper syrinx, larynx, trachea, bronchi and in the lungs.

Aspergillum spores are found growing throughout the entire world in great quantities on days that the weather is favorable and there is an ample food and oxygen supply. They are very hardy and resist even the most weather conditions, and as so, they are extremely hard to get rid of.

Transmission

These attack your birds in relation to the following criteria:

  • There are an increased number of spores in the air:
  • Your birds are exposed to the infected air for enough time:
  • Depending on the age of your birds, the youngest and oldest are most affected:
  • You over use antibiotics, especially the tetracycline based ones and/or you are providing anti-inflam-matory drugs to your birds:
  • Malnutrition:
  • Your aviary or cage has poor ventilation and/or conditions favorable to the inhalation of already formed spores:
  • Presence in the air of respiratory irritators (ammonias, tobacco smoke, gases caused by disinfectants and others):
  • Communicable diseases.

An example of the effects of stress as related to the susceptibility to the Aspergillum in birds is as follows: regular sea gulls that seem to be healthy, when caught in areas of a low density of Aspergillum spores and kept captive tested positive for sickness after a while though chickens kept on the same premises did not get sick at all. The most frequent method of contact is by breathing spores in the air. The one other way these spores can begin to grow in the birds is when transferred in an injury, especially to the air sacs.

Aspergillum is a strictly an environmental transferred sickness and cannot pass form one bird, person to another. The infections or other sickness that the birds get during this time that kill them are because of the depressed immune system. Healthy birds exposed to high concentrations of these spores are resistant. Penguins (as are other water fowl and reptiles) are very susceptible to falling pray to Aspergillum, especially those that live in captivity. Perching birds and psittacines are very much less susceptible. For these many years now of our avian clinic the most common birds with Aspergillum that have been brought to us are the African Grays, Blue Fronted Amazons and "mainates."

Birds have a rather efficient system to keep their respiratory systems clean; it consist of mucus covering of the entire system that acts like a mop that eliminates them from the system (out the mouth and nose) before they can germinate. The abundance of dust with a low humidity provokes the paralyzation of this form of defense.

Aspergillum and other fungi grow rapidly in decomposing organic mater. A damp type material used in building nest will favor its growth, contaminating the eggs and in turn the youngsters born in said nest. Dusty or wormy feed will also encourage the growth of fungi spores.

Symptoms

Symptoms can appear in from almost unnoticeable forms to chronic illness.

Acute Aspergillum is fatal. This occurs when the bird inhales a large quantity of the fungi and it grows very rapidly. The symptoms are: loss of appetite, difficulty breathing and finally death, usually with no prior notice of sickness.

Chronic Aspergillum is much more the common form of the sickness, presenting itself typically in small nodules or spread out in the lungs or air sacs. The nodules you see will be of white, yellow or green usually on the syrinx, larynx, trachea and bronquials are mostly the areas involved. The symptoms are variable: difficulty breathing, listlessness, depression, and going light. The fact it, this sickness attacks the respiratory system right at the beginning and these are the very first signs of this illness. Some birds even seem well but in the autopsy, the lesions are present.

Weakness brought on by bacterial or viral infection, or some parasite give the Aspergillum fungi a very comfortable and opportune dwelling place and many times cover the actual cause of death.

Not all Aspergillum are fatal.

Lesions affecting the upper respiratory tact (trachea, syrinx [pl. syringes] and bronchi) are usually frequently associated with:

  • Voice changes (less volume, change of tonal quality when talking or vocalizing.
  • Audible breathing sounds.
  • Respiratory difficulty: frequently this symptom is first noticed after a prolonged or moderate period of activity or exercise.
  • On occasion the Aspergillum affect the Nervous System, producing lack of coordination in movements or even paralysis.

Diagnostics

Confirming the sickness in the bird is rather difficult when it is still alive. Once dead, the findings of lesions in the respiratory tract would be proof to you. The clinical history, laboratory analysis, x-rays, endoscopes and so forth are that can help us in the diagnosis.

A couple of other sicknesses can manifest themselves with some of the same symptoms, such as are Ornitosis and Megabactosis.

In general, there is little hope, with or without treatment.

Treatment

Application of treatment is rather insidious, many times being of intravenous method. There are several medications that are helpful but all of them have drastic side effects. Thus, it stands only reasonable to find a specialized avicultural veterinarian in order that the bird is properly treated according to the type it is.

Control

The best form of control against this sickness is its prevention. A dirty cage, bed or housing is the culprit. Reducing the amount of dust by providing better ventilation helps a lot in preventing contamination. Of course, natural ventilation is better than forced air.

Another way to prevent Aspergillum is to reduce the stress in your birds by minimizing such as: malnutrition, fecal buildup, use of antibiotics, and unnecessary amounts of food….

© Enrique Moreno