HAMILTON & DISTRICT BUDGERIGAR SOCIETY INC.



ASPERGILLOSIS:

Fungal Infections in general:
--------------------------------
Fungi belong to a group of primitive plants, The vast majority live independently but some are parasites on other plants, and relatively few mammals and birds. Most are in the form of filaments one cell thick, which grow into tbe material or tissue that nourishes and protects them. Because of their delicate structure, fungi are vulnerable to drying and most require moisture, warmth, and protection from light. These requirements are admirably provided for in the bodies of warmblooded animals; oxygen and nutrients are also readily available. When the environment dries out, the filaments produce spores which are easily carried in air currents. Luckily only a few fungi have so far adapted themselves to become parasites of birds.

Aspergillosis (Aspergillus fumigatus infection):
This is a disease of the respiratory organs of many birds. The fungus grows in the lungs, air sacs, and syrinx (sound box) causing lumps and nodules. Occasionally the skin and organs are attacked. In Canaries the cream-colored nodules have been found to be mainly about the tongue and air passages. Syptoms are usually signs of bronchitis and/or pneumonia. Gasping, hard breathing with an open beak as in asthma is typical. Ratttling or wheezing may be present. The birds may also become thin, have diarrhea and is fatal to most birds.
Aspergillus fumigatus is one of the common "green moulds" frequently seen in partly used jars of jam, on stale bread, decaying food and other organic matter. It is widely distributed throuhgout the world and together with related species is mainly found as a parasite of birds. In young chickens it causes "brooder pneumonia". It affects many species of birds as well as mammals and man, all becoming infected by inhaling or ingesting the fungus spores. The disease is particularly common in penguins, waterfowl and recently captured wild birds, especially if they have been subjected to adverse conditions of management and transport. Seeds, chaff, musty hay, straw and other dusty materials are rich sources. Small numbers of spores are tolerated by the body, but large numbers can cause disease. When established, the fungus can produce poisonous substances or toxins which damage various tissues in the same way as do some bacteria.

CLINICAL SIGNS:
Usually only debilitated birds suffer from the disease. Weak, overcrowded birds and those kept in unhygienic conditions are most prone, especially nestlings and old birds. The respiratory system is the favourite site for Aspergillus. The filaments multiply, branch, and mat with the tissue exudates. Then they tend to block the air passages and fill the airsacs. The internal nares or nostrils, sinuses, and other cavities of the head, including those under the eyelids become filled with cheesy, yellow masses. More frequently, the lungs and air sacs, especially those in the thorax and abdomen are affected. Occasionally the fungus may resemble gouty deposits at post-mortem examination, unless microscopical examination is carried out. The main signs in an affected bird are gasping, laboured and rapid breathing. Occasionally wheezing may be heard from a distance or when holding the chest to the ear. At times it is possible to hear clicking sounds indicating pieces of loose fungus or exudate flicking to and fro in the larger air passages. Although the disease can kill in a few days, in psittacines and some other species it tends to progress for weeks or even longer, especially in adults. Frequently death may occur with little previous outward sign except for loss of weight and progressive depression. In young stock, depression and sometimes convulsions are the main signs.

TREATMENT AND PREVENTION:
Prevention is almost entirely a matter of maintaining a high standard of nutrition, hygiene and housing, and having luck with weather conditions and in the purchase of clean seed. Dust is the main enemy, and birds living in a planted aviary free from loose litter are least likely to contract the disease. Untidy food stores with old grain sacks, bags, papers and other oddments strewn about, or dark, makeshift sheds are all ideal for the production of fungus spores, particularly when the weather is warm and humidity high. Continuous use of antibiotics, for as little as two or three weeks, favours the establishment of fungal infections such as aspergillosis. Treatment is unsatisfactory, especially as the disease is sometimes impossible to diagnose during life. There appears to be no effective substance which can be used internally without eventually killing the bird. Some success has been claimed using potassium iodine in the drinking water as a preventive, but it is of doubtful value. Exposing birds to nystatin aerosol by the use of a nebulisor has also been suggested, but laboratory tests have shown that Aspergillosis is resistant to this antibiotic. More recently, intra-venous amphotericin has been suggested, but it may well be toxic. The drug griseofulvin, which is effective in ringworm and other fungus infections of the skin has little effect on Aspergillosis. Some antibiotics will lessen the symptoms of the disease along with vitamins high in A, and calcium. Some relief has been shown by misting with Miconade Flourocycine or Amphoteracine-B. If you suspect fungus growth you can use a 1 percent solution of copper sulphate as a fungicide disinfectant to clean items in your aviary or cages. Rinse with warm water and let dry before placing birds back in. Never use any treatment or antibiotic without the advise of a vet. Some other results have been successful using 'keto-conazal per on' over one month. For lung and air sac aspergillosis, ultrasonore misting with miconade flourocycine or amphoteracine-B might be helpful. Just remember the main cure for this disease is a preventive. Never give old or moldy seeds, clean the avairy regularly, do not give spilled seed a chance to become moldy by sweeping it up regularly.

E-Mail: berniehansen@sympatico.ca

[ GO BACK ]

GO [HOME PAGE]


Hamilton & District Budgerigar Society Inc.