The three harmless letters "AGY" (= Avian Gastric Yeast) symbolise a malicious, incurable and in the progressed stadium deadly disease. This disease is comparatively frequent among budgies, but also several other bird species can be affected. AGY is highly contagious; if one bird feeds another the pathogen can be spread. In many birds, the diesease appears in a cronic course without any symptoms interrupted by acute episodes from time to time. Therefore an ill bird can be misjudged and considered to be healthy during the period without any symptoms. A bird who seems to be healthy and who had just become a new flock member can introduce and spread the disease. In the worst case, the whole flock can become infected without showing any symptoms for several weeks or months. That's the reason why this disease is so malicious.
Typical symptoms of an AGY infection
During an acute episode of the disease, the bird seems to be weak, it's feeding excessively and despite of this it's loosing much weight within just a few days. This happens because the disease has a negative influence on the digestion and as a result of this, the nutriments cannot be absorbed properly by the bird's organism. A lot of affected birds regurgitate indigested seeds together with thick mucus (in some cases it smells very bad). Indigested seeds can as well be found in a sick bird's droppings. In spite of a seemingly adequate ingestion, the bird is starving slowly until the point of no return when its organism starts to digest itself.
That's the beginning of the end.
What is the course of this disease?
In accordance with the actual knowledge about AGY so called megabacteria are responsible for the above described symptoms. These pathogens settle in the digestive tract of a bird (on the mucous membranes).
But their name is confusing since megabacteria are no bacteria at all. They are fungus-like or more precisely yeast-like organisms as scientists have found out in 2004. During their research they have learned more about the pathogen and described it as a new species; it was renamed into Macrorhabdus ornithogaster.
Birds suffering from a megabacteria infection often show secondary infections caused by bacteria. Both types of pathogens, Macrorhabdus ornithogaster and bacteria like Streptococcus spp. and so on, can interact and make the health status become worse so that the bird's life is in danger.
If Macrorhabdus ornithogaster has spread in a bird's body and no symptoms can be seen so far, then we speak about a so called megabacteriosis or macrorhabdiosis which is the newly introduced medical term for this disease. Once a bird shows any symptoms like vomiting or loss of weight, we have to deal with a disease called going light (GL) or wasting disease. In fact this is the description for a progressed state of an infestation with Macrorhabdus ornithogaster combined with other pathogens.
So far, scientists and avian vets weren't able to find out whether the presence of megabacteria in a bird's organism can lead to an outbreak of GL or if it takes more factors to cause this appearance of the disease. Many experts claim the presence of bacteria that are responsible for secondary infections is a pre-condition for the outbreak of GL.
Infection with megabacteria = GL?
The basic fact is: If a bird was tested positive for megabacteria, this doesn't automatically mean that the animal already suffers from GL. If the infestation with megabacteria will be diagnosed in time, then in most cases the outbreak of GL can be prevented by an effective treatment. Here in Germany, birds have to be treated with Amphotericin B (Ampho-Moronal), a fungicide drug. Avian vets also examine smears to find out whether there are bacteria or not. Regrettably even the experts don't seem to be at one with each other concerning the medication duration, the frequency and the dosage of the drug. In many forums one can read about different therapies, but it's not recommended to change the dosage or frequency without discussing it with the attending avian vet.
Special diet for megabacteriosis or GL patients
According to most of the experts, birds who suffer from megabacteriosis or even GL should not get any food that contains sugar such as dextrose, fructose or glucose. The pathogens benefit from sugar and a higher reproduction rate will be the effect. Therefore fruit, bakery products, or even some food supplements (most liquid vitamins contain sugar!)
should not be served to a megabacteria or GL patient, many avian vets say. But there are some doctors who say that during the treatment with a fungicide drug, birds are allowed to have some fruit. Please discuss this topic with your vet in each individual case to make sure your bird's therapy will not be ineffective due to a wrong diet.
Supporting therapies and treatments for megabacteriosis/GL patients
The budgie owner Bettina Buckermann from Germany received the diagnosis GL in autumn 2001. Her male budgie Pierrot became sick and the vet found out that megabacteria caused his severe health problems. From this day on, Mrs. Buckermann tried to support Pierrot's organism by the aid of some additional treatments. She wanted to share her knowledge and experiences with other bird owners:
"The first treatment in the avian clinic was successfully, but 9 weeks later Pierrot suffered a relapse. The second treatment followed, and 5 weeks later another relapse weakened my bird. We could not take the responsibility for another treatment because of side effects of the drugs we used to cure the bird. Pierrot looked very agile and active despite he was suffering from the infection with megabacteria. I was wondering what I could do for him and therefore I read a book about the medical use of herbs.
In this book I found the information that thyme has fungicide effects. From this day on I served thyme tea to Pierrot every day (2 small teaspoons of the herb for 250ml of water). Regularly the vet examined the droppings and he found out that the number of the pathogens decreased and finally disappeared till the 9th and 12th week. Because of a possible latent megabacteria infestation in the glandular stomach, I added 1/2 teaspoon of ground anise to the thyme tea."
Certainly you have to make sure your bird accepts the tea. If so, you can try to prepare a mash from the herbs and serve it to your bird. Mrs. Buckermann's budgie Pierrot accepted this mash and she noted: "You should not serve too much mash to your bird. Otherwise problems with kidney (due to proteins) and liver (due to fat) can result from this special diet. As Pierrot has been regularly weighted and checked (the values were listed each time) I have been able to learn quickly from the thyme therapy."
Certainly thyme and anise don't replace any kind of (preceding) treatment with antifungal drugs, but it seems as if these herbs really have a remarkably positive effect on a bird's health.
Mrs. Buckermann continued: "The mash I prepared for Pierrot consisted of a small quantity (like a pea) of low fat curd cheese (most probably to many proteins in the long run) and cereal baby food (without sugar and milk) and a pinch of thyme and anise tea. For feeding I have invented a special procedure. I put the mash on the tip of my finger and put it into Pierrot's beak. Well, a lot of patience was needed! Even after he had recovered, I was still feeding Pierrot with this thyme-mash from time to time (not daily)."
Mrs. Buckermann wanted to point out that this herb mash is not the one and only treatment for GL patients. And furthermore she said:
"A correct dosage is of high importance, because other health problems can appear in case of an overdose. You should start the therapy with just a small quantity and a light thyme tea. I primarily watched the consistency of Pierrot's droppings, weight and health conditions every day and documented it. You should not feed your bird just on this mash, this would be far too one-sided. I served a lot of fresh food like fruit, vegetables, and occasionally a little bit boiled yolk and sprouted seeds as well. Do not feed a bird too much in spite of you mean well. My budgie gained weight and suddenly he was overweighed!"
Similar diseases
If your bird throws up all his food again and again, not in each case megabacteriosis or GL is the reason for this repetitive regurgitation. There are a lot of similar diseases which can evoke symptoms as regurgitating or weight loss despite eating much, among them Candidiasis. If there are some indigested seeds in the bird's droppings, then for example the bird possibly could be suffering from enteritis or something similar. Therefore it is recommended to visit an avian vet immediately if you observe vomiting or indigested seeds in the droppings; your bird should be examined thoroughly.
In any case it is very dangerous for a bird if indigested seeds are egested because any malfunction of the digestive tract can lead to deficiency symptoms or even to starvation within just a few days.
German version of this text: Gaby Schulemann-Maier,
translation of this chapter: Ales Tronícek.
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