FUNGOID INFECTIONS 


By F. Evers, veterinian in The Netherlands, Article taken from the Internationaal lori journaal.


Aspergillosis.


In Psittaciformes, fungoid infection is one of the most frequent causes of illness and death. Unfortunately, relatively little attention is given to these infections. One of the main reasons for this is the fact that the diagnosis cannot be made in a simple, clinical, investigation.


The most common symptom of a sick bird is its sitting in a ball. The bird is less lively than usual and the feathers are not held closely to the body, but wider. In combination with these symptoms one often sees signs of breathlessness.

The general indications may be caused by infections and abnormalities may not necessarily be caused by infections from germs. The germs can be divided into viruses, bacteriae, parasites and fungae. Diseases of the air tract may be caused by any of these.


A very common cause of air tract problems in birds is fungae, especially Aspergillus. The spores can be found anywhere and are brought into the respiratory system by simple breathing. The respiratory system of birds is rather different from that of humans and other mammals. The main difference is the presence of several large airchambers in the body. These are especially very prone to infections with fungae. Whether an infection develops depends on the condition and the resistance of the bird. Deficiencies in the food, e.g. lack of vitamin A, are important for the development of the disease, but an infection with fungae can also be secondary to another infection, major stress or prolonged use of medication like antibiotics. The quantity of infectious material is also important. Considering the fact that fungae grow very well on rotting material, it is important to remove faeces, old wood and damp food. With lories, who waste a lot of wet food, cleaning and disinfecting have to be especially thorough.


When a bird has a fungal infection of the air sacs, one may see symptoms like loss of liveliness, breathlessness, diarrhoea and loss of weight. These are the same symptoms that occur in other diseases. Often the disease has a chronic course, but very acute infections with sudden breath deficiencies and death within a few days also may occur. Sometimes one even sees death without any previous indications.

Another common location for fungal infections is the syrinx, where the voice of the psittacus is produced. We then notice oppression, combined with wheezing or rasping breath, coughing and change of vocal pitch. It is important to act quickly if one notices these symptoms, because the animal may suffocate.

It is also possible that a fungal infection is located in the small air sacks inside the head. This can be recognised as a local, whitish translucent swelling.


Especially the non-specificity of the symptoms makes it difficult to diagnose fungal infections correctly in a simple clinical investigation. This makes treatment risky. Although antibiotics are very helpful in bacterial infections, they are contra-indicated in case of fungae. Worse, they stimulate their growth. A sure diagnosis is of vital interest to the bird. This can be achieved by a combination of endoscopy and microscopy. In the case of an erroneous diagnosis it is possible that the wrong treatment is started and the condition of the bird deteriorates.


Next to infections of the air tract we also find infections in other parts of the body. Fungae have, in post-mortem examinations, been found in the liver, the kidneys and the intestines. Depending on the location of the infection, the symptoms are more or less specific for the affected organ. E.g. in case of infected intestines, one may find diarrhoea.

Another possibility is an infection of the skin, we then find distorted feathergrowth and -structure. In case of infected eyelids sometimes a caseous thickness of the eyelid can be seen.


For treatment of fungal infections there are several remedies, some of which are flucitosine and ketoconazole. Unfortunately, the results have often been disappointing. Of more recent date is itraconazole, but it has not been legalised for use in birds yet.


Candida


Candida is a yeast and belongs to the group of the fungae. Whereas Aspergillus mainly infects the airtract, Candida is usually found in the digestive tract. Very often Candida can be isolated from the stomach and intestines of healthy birds. It seems to be harmless for the birds, but under certain conditions the balance will be disturbed and the Candida does become infectious. Here also the condition and resistance of the bird are important. Deficiencies in the food, like vitamin A deficiency, lack of hygiene and prolonged use of antibiotics are predetermined factors. Even though mature birds may be infected, especially the young ones are sensitive. Deaths of psittacine babies in cases of blockage of the crop are quite often caused by Candida. In the crop Candida may cause local or multiple foci, and also the mouth, stomach and intestines can be affected. Symptoms may be: a crop which does not empty, vomiting, shaking of the head, lack of liveliness, weight loss, thin faeces and death. Especially in lories infections of the intestines are often caused by Candida. The most important signs are vomiting, diarrhoea and weight loss. The yeast may also infect the nasal cavity and the eyes. The result is nose-dripping, oppression and eye-infection. The beak of a psittacus is also liable to get an infection with Candida. This often happens after trauma, but infections without previous trauma have also been diagnosed. The symptoms are loss of horn and holes in the beak. To certify the diagnosis Candida the avian veterinarian uses microscopic investigation, cultures and endoscopy. As with Aspergillus, the symptoms of Candida are non-specific, and may lead to another diagnosis which requires a different treatment.

The most common medication for Candida is Nystatin (R).

In the case of focal infections of the beak local treatment with diluted enilconazole may have the required effect.

SiteLock

© Copyright. All Rights Reserved.