Health and diseases

The breeder can do a lot to prevent diseases in birds. The most important preventive measures have already been discussed in detail in the chapter Aviary design. However, even if we have housed the birds under optimal conditions and the care is excellent, diseases can still arise. Sometimes a disease can affect an entire population in the aviary. It is therefore necessary to observe the birds on a daily basis. Any change in behavior, defecation or plumage can be an indication of a disease.
If this is noticed, do not hesitate and isolate the bird to prevent transmission of the disease to other birds and to allow the bird to recover in a quiet environment. Every bird keeper should have a so-called sick cage at hand. By providing heat in or above the cage, the bird must be placed at a temperature of about 30 ° C. The bottom of the cage should be changed every day. I use a piece of newspaper that can be easily removed. This daily refresh is necessary to break any infection cycle. The bird must continue to eat and drink. Sometimes it is necessary to offer some soft food if the bird is no longer able to peel the seed properly.
Never just start providing medication if the diagnosis is not conclusive. Bird keepers may have a lot of experience, but are no veterinarians. Therefore, consult a specialist of birds. Providing medication without knowing the cause, will only weaken the bird and minimize the chances of recovery. Be sure to consult a veterinarian if multiple birds are affected by the disease. Check the bird's condition regularly. When it goes downhill and the bird suffers, be brave and end it by breaking the neck
Most people don't have the right background to diagnose a bird. Therefore, the table below is intended as a guide only and NOT in lieu of professional medical advice and diagnosis.
Often investigation of dropping, provides a definite answer about the disease. To collect the material, a piece of aluminum foil is placed in the sick cage and removed if faeces have been deposited. The manure is best examined fresh. In any case, it is recommended to keep the sample in the refrigerator. Manure is usually examined by a veterinarian. There are also non-veterinarians who can make a reliable diagnosis based on the test. If you have a bird with urgent metabolic problems, I may examine the droppings for you, but membership of the SEC is then required.

Possible causeSymptoms

E. coli

This disease can occur in birds 1-8 days old. The nest feels wet and the female birds' feathers look sweaty. The nest can also smell foul. In most cases, the young birds die. Older birds can be treated with an anti-biotic such as colistin.


Atoxoplasmosis is a real disaster for cage birds. Infected birds die quickly. Examination shows an enlarged liver with an unnatural blue / purple color. A cure is not existing, but preventive medication is possible, especially just before and during the breeding season.


Mainly young birds are the victims. They stop eating (enough), the faeces are liquid and the intestines are red and swollen. Coccidiosis is less "deadly" than atoxoplasmosis and can be treated. Finicoc, Baycocx or Esb3 can be used for treatment as well as preventive.


The infectious disease incorrectly called "Megabacteria" is actually caused by a yeast (Macrorhabdus ornithogaster). When the faeces of sick birds were examined under a microscope, elongated organisms were seen. Because they looked somewhat like rod-shaped bacteria, but were much larger, they were called Megabacteria. When a bird is infected, the faeces are watery thin and often contain a brown, loose substance. The yeasts that cause this multiply in the stomach. Whether a bird suffers from Megabacteria can only be determined by microsopic examination. Treatment is best done by means of medication also used in the human medicine. Good results are achieved by using "Fungizone" a suspension with the active ingredient Amphotericin B (100mg / ml), which is administered for 14 days at a concentration of 0.6 ml / liter. Another indication for being infected with Megabacteria is the presence of undigested seeds in the stool. The gizzard is sometimes pushed backwards so that it can be felt as a kind of "egg" in the abdomen. This is because the glandular stomach is inflamed and thus enlarged, pushing the gizzard back.

canary smallpox

The name suggests that only canaries suffer from this. This is not true. Our European seed eaters are also sensitive to this. Smallpox comes in two forms for the external form and the internal form. With the external form, wart-like conditions appear around the beak, eyes or on unfeathered skin. In the internal form the disease is inside the throat, trachea and lungs. The bird is clearly gasping for breath. The virus enters through the skin. Mosquitoes are the transmitters. No treatment is possible. Most birds die. Canaries and finches must be vaccinated preventively to avoid the disease. This is the only solution. A bird keeper who has had to deal with canary smallpox problem wiil definately vaccinate annually. Vaccination takes place in June / July.


Trichomonas is a respiratory infection. The bird has difficulty breathing and there may be mucus on the beak. When the bird shakes its head, you will see droplets flying around. Treatment with Tricho plus (Oropharma)


Campylobacter is a bacteria responsible for a large number of food poisoning incidents in humans. However, a campylobacter infection can also occur in birds. The yellowish droppings of the birds show undigested seeds. The disease can be treated with erythromycin (5%), which is dosed via the water. The medicine does have a different taste. It must be ensured that the birds continue to drink. Baytril is also a good medication


Dermatomycosis is an infection caused by the pathogenic fungus Trichophyton or microsporum. The symptoms are the presence of a white powder on the feathers. Later the feathers can even fall out. External treatment of the affected areas can be done with Nizoral or Dactarin. Nizoral can be used long-term without side effects. The infection can also be transferred to humans. Caution and strict hygiene is therefore essential. Other agents that help well are imaverol (active substance enilconazole) external and trisporal (intraconazole) internal


Aspergillus is a fungus that we classify among the opportunistic pathogens. Birds are only affected if the conditions for growth and infestation for the fungus are ideal. If birds are kept in a humid environment with little ventilation, the fungal spores will be inhaled and germinate in the trachea. The birds have very difficult breathing. Examination shows white spots on the membrane. External treatment with Itraconazole or Nizoral. Aspergillosis often arises as a result of vitamin A deficiency

Father mites

These parasites feed on the keratin causing feather shedding and messy plumage. Treatment with Finion or Bird spray (avoid contact with the nose entrance and the eyes). Feather mites can also be treated with anti-trachea mites solution from Bogena. (Once every 10 days on bald skin and repeat this 3 to 4 times). Also Oramaec (1 day via the drinking water once every 10 days and repeat this 3-4 times.)


These parasites (Dermanyssus avium) hide in dark places and attack at night. These invasions can be massive. Young birds in the nest can die from anemia. To prevent red mites, cracks and seams should be avoided in the aviary or cage. Wooden constructions are best sealed with a silicone sealant. White paint is better than dark paint. Nest boxes should not be hung rigidly against the wall, but kept at a distance with, for example, a few nails. If there are red mites in the cages, this can be recognized by restless birds, which are pecking and scratching the plumage all day long. Places where parasites reside should be treated with a spray. I always apply a fine layer of Finion powder under the sisal nest baskets. This is a natural insecticide. There are also mixtures of dried herbs for sale today that are said to have the same effect. I have not had any positive experiences with this so far.

The life cycle of Isospora canaria and Isospora serini

Coccidiosis and atoxoplasmosis are protozoan diseases. Coccidiosis is caused by the parasite Isospora canaria. The cause of atoxoplasmosis is the closely related parasite Isospora serini. The infection cycle of both parasites is almost identical. However, they differ from each other in one important aspect. Unlike isospora canaria, isospora serini is able to "penetrate" through the intestinal wall and settle into vital organs through the bloodstream. Liver, spleen, lungs and brain can be affected by this. This often leads to a rapid death of the bird. Infection with Isospora canaria is usually just as deadly for young birds, but is usually milder for adults. An outbreak of coccidiosis or atoxoplasmosis can spell disaster for bird keepers. During the breeding, everything is aimed at keeping these parasites out, or at least keeping the infection pressure within proportions.

A lot of scientific research has been done in the field of parasitic diseases. This is mainly because malaria, which is also caused by a protozoan, still causes millions of victims in tropical regions. Parasites are also a major threat to intensive chicken farming. Here, too, preventive action must be taken to avoid serious outbreaks. There are hundreds of different types of protozoa, most of which are very host specific. However you look at these parasites, one thing has to be said, nature has equipped these tiny single-celled organisms with a highly specialized and sophisticated mechanism to survive. Interesting enough to consider the life cycle of the two parasites that can cause so many problems in our hobby.

The infection cycle starts with a bird infected with a parasite. The oocysts, they carry are excreted with the droppings of infected birds. At that time these germs are not yet able to infect a new host. A ripening process outside the bird's body (in the droppings) must precede this. Sporulation (maturing) takes a number of days. The conditions must be favorable, moisture and heat are necessary to initiate and maintain sporulation. An immature oocyst usually contains a sporoblast (immature spore). First, a division takes place in the oocyst, creating two sporoblasts. The sporoblasts now form a cell wall. This sporoblast turns into a sporozoite. Subsequently, division takes place twice again, so that four sporozoites are formed. Only after going through this cycle has the parasite entered the virulent stage and is ready to infect a new host.
It will be clear that this is an opportunity for the bird lover to break the cycle. Keeping the cages clean and especially removing the manure is very important to stop the ripening process in the bird house and to remove any ripened spores with the manure before the parasite can be absorbed by a healthy bird. In dry, well-ventilated enclosures, the oocysts will be much more difficult to sporulate than in humid warm conditions.
When the matured oocysts are taken up by birds, they settle in the intestinal wall of the small intestine and invade an intestinal wall cell. Another change now takes place as they start to break down the intestinal wall cells. At this stage, the infected bird has become a sick bird, as the parasite will now start using the host to survive. The breakdown of the intestinal wall cells is now also visible when we ilook at the bird's belly, the intestinal loops then look red and irritated.

The next cycle takes place entirely within the bird. This is the asexual reproduction cycle, in which large quantities of merozoan cells are formed from the sporozoan cel, which then search for new cells to infect. This creates a process in which more and more cells are attacked. The bird's condition will now deteriorate visibly, because cell wall cells are now being broken down en masse and the bird's digestive process is completely disrupted. The bird has now also become particularly sensitive to other, usually bacterial, infections.
Over time (a few days to a week), the cycle of the parasite changes again. Some merozoic cells turn into gametes. Specific female and male cells are now being created. After a male and a female cell are fused (the sexual reproduction) a zygote is formed. In a subsequent phase, the zygote begins to turn into an oocyst. These oocysts now exit the small intestine and make their way out. This brings us back to the first step in the cycle.


The Mega Bacterium is an opportunistic pathogen. Opportunistic means that healthy birds can carry the infection without immediately leading to a clinical picture. Only when the bird has a weakened immune system, rapid multiplication can take place and the bird can start to show signs of illness.
The name megabacterium is actually incorrect. The organism that can cause problems in our birds is called Macrorhabdus ornithogaster in full and is not a bacteria, but a fungus. The fungi family includes molds, yeasts and fungi. When M. ornithogaster was isolated from sick and deceased birds, there was no means to cultivate the organism in the laboratory. Elongated cells were observed under the microscope, which were very similar in shape to rod-shaped bacteria, except that these cells were many times larger than a bacterial cell (about 20–80 micrometers in length). The term “mega bacterium” was therefore obvious. Because the organism also occurs as a pathogen in chickens, a lot of research has been done in the last 10 years. The organism can now be cultivated on a nutrient medium and a lot of work has been done to develop a suitable medicine.

When does M. ornithogaster cause a problem for our birds?
As mentioned, the yeast also occurs in small numbers in birds, which do not show symptoms. The onset of stress, which reduces the bird's resistance, can already cause the yeast to multiply in the stomach to high numbers and make the bird sick. We see this phenomenon with more infections. Often a megagabacteria infection is accompanied by another infection. Most microscopic specimens where I could observe M. ornithogaster also showed amounts of coccidia. It is then important to treat both.
Often M. ornithogaster flares up when a bird is moved and stress occurs. A bird's resistance can also be weakened by one-sided or incorrect feeding. Poor housing and inadequate hygiene can also be the cause of infection. M. ornithogaster causes inflammation in the glandular and gizzards. This causes the digestion of the food to fail and the food to accumulate. This is also the reason that the bird wants to keep eating. Despite the fact that a lot of food is absorbed, it is not digested further. With a full crop and stomach, a bird actually dies of starvation.

The diagnose
The external characteristics of a bird that has an M. ornithogaster infection are the following:

    The bird spends a large part of the day by the food bowl. It eats and seems insatiable, yet the bird is visibly losing weight.
    The bird looks unhealthy and has hanging wings. Most birds will only “bulge” when the disease is already at such an advanced stage that a cure is almost impossible.
    The manure is watery / slimy thin with a green core. Sometimes undigested seeds can be observed in this.

The above features can also be caused by other infections. A microscopic examination of the manure is therefore necessary and provides an immediate answer. If elongated rod-shaped cells are observed under a microscope at 400x magnification, this is always an infection of M. ornithogaster. Most cells are in the green core of the stool, so this should be examined. Staining of the preparation often gives a clearer picture, but is not really necessary. Do not forget to also look for secondary infections, for example the presence of coccidia. Because few bird keepers have a microscope, one will have to consult a specialist bird veterinarian for diagnosis. Collect some manure with a piece of cling film and send it in or bring it with you when you visit the vet with the bird.

Antibiotics such as Baytril have no effect on yeasts. Research in the poultry sector has shown that treatment with amphotericin B does produce the desired result. Aphotericin B is also used in human medicine for the treatment of yeast infections of the intestines or genitals under the trade name Fungizone. In sick birds, Fungizone is given in a concentration of 0.6 ml / liter of water for 3 weeks. It is better to apply the product 3 times a day directly into the crop with a crop needle. The treatment can then be shorter, but not everyone dares or can work with a crop needle. A bird can only be declared cured when no cells are visible in the microscopic image. Amphotericin B acts on the yeast cell wall, causing leakage and inactivating the cell.
If a bird has contracted the infection, it should be set aside. Not because an M. ornithogaster infection is very contagious, but the bird must be treated and preferably also warmed up in a sick cage. Many times, Baycox or EsB3 are used too quickly if a bird has a stomach / intestinal problem. Precious days are lost and the bird is getting sicker. An infection with M. ornithogaster can be cured well, but you can intervene quickly with the right medication.

This is a bacterial infection. The infectious organism causing the disease is Escherichia coli and the infection takes place in the intestines of the bird. This causes severe diarrhea, so that the faeces are no longer surrounded by a membrane and can no longer be removed from the nest by the female bird. This creates a wet nest where a mostly green or yellow colored faeces can be seen. The name colibacillosis raises questions. Bacilli are microorganisms capable of forming spores. Escherichia coli cannot do this and only occurs as a vegetative organism. However, both names are fully established and it doesn't really matter much. In the poultry sector, the organisms that cause disease are called APEC (Avian Pathogenic E. Coli). In addition to the colibacillosis discussed in this article, E. coli can cause a wide variety of other types of infections, including septicemia, ovarian inflammation and yolk residue inflammation. In the latter case, the embryo dies in the egg or very shortly after hatching. Escherichia coli occurs naturally in the intestinal tract of mammals and plays an important role in digestion.
Pathogenic (pathogenic) variants can also be isolated from apparently healthy animals. There are as many as 12,000 different E. coli types, which can only be distinguished from each other with advanced antigen techniques.
If one bird in the nest is infected and diarrhea occurs, the other chicks will become infected very quickly. Within a day or two days at the most, all chicks will die as a result of dehydration and the inability to digest the food. Often a foul odor can be observed at the nest, which is caused by decomposition products in the manure. As with many other infections, there must be several factors involved that actually make E. coli a pathogen. Hygiene plays a very important role in this. The infection pressure for the nestling should be kept as low as possible. Overcrowding must be avoided. An aviary floor, where feces have accumulated and contaminated drinking water are sources of infection. The infection is transferred to the nest via the parents or directly to the nest young through the food. Moisture is also an important factor determining whether the disease can manifest itself. Perhaps this is the reason why colibacillosis infections occur more often in wet years than in others. The bird's resistance also determines whether the disease develops. An improperly balanced (egg) nutrition can make the young extra sensitive. If a nest is infected, the young must be placed in a clean nest (e.g. a clean identical basket).This should preferably be checked daily and replaced again if desired. Rapid action is important. When the first symptoms appear, it is usually already too late. The disease can be cured at an early stage with a suitable antibiotic. In the past, tetracycline was often prescribed, but this agent has the side effect that it can promote goiter acidity. Nowadays colistin (polymyxin E) or TMPS (trimethoprim sulfadiazine) is usually used. If an outbreak occurs in your mixed aviary, consider starting treatment for the entire bird population, even if another nest still looks healthy. Probiotics are also tried as a preventative measure. But, with a few exceptions (chickens, waterfowl), birds have no intestinal flora and conditions in the intestines are such that probiotic bacteria will not colonise the gut. Providing probiotics will therefore not have any positive influence on the prevention of E. coli infections in the intestinal system.


A respiratory disease can have various causes. Sometimes different causes have the same clinical picture. The bird gasps, shakes its head and sometimes we see the bird shaking wisps of slime from its beak. In 2009 there was a small epidemic among wild finches of Trichomonas gallinae (the yellow). Greenfinch in particular were the victims of this. However, this has not led to any problems in aviculture. Trichomonas gallinae is a protozoan, from a large family, which mainly provided it on the mucous membranes. In humans, Trichomonas occurs as an STD, which is on the rise. If “the yellow” appears in your birds, treatment with Tricho plus.

Trachea worms can mainly occur in birds in the outdoor aviary. This is because they host snails, centipedes and worms. Birds that eat an infected host can become infected. Here too, the bird shakes its head frequently to get rid of the worm and it is difficult to breathe. There are various means available for killing windpipe worms. Ivomec is a product that is widely used in the treatment of various parasites. Trachea mites Here too, breathing is difficult and the bird often sneezes. Of the finches, the putter seems to be the most sensitive. Trachea mite can easily be treated with anti-trachea mite (Bogena) or Ivomec. Active ingredient Ivermectin 0.12%., Make sure that you apply the droplet in the neck carefully and the bird cannot absorb the agent through the beak.

Bacterial infections are probably the biggest cause of respiratory illness. Bullfinches and gross beaks in particular seem to be extra sensitive to this. The bird gasps and shakes its head continuously. Mucus can be seen flinging from the beak. The head is also wet and the walls of the cage become soiled with mucus residue. Often this has to do with insufficient ventilation when the birds are housed indoors. Usually a bird cannot overcome this condition on its own. To cure this persistent infection, the medication “anti-Respiratory tract mix with expectorant” of the Vet Clinic Hulst, in the Netherlands helps.

Great care must be taken in finding a vet knowledgeable of birds. Most vets are specialised in small pets, but often lack the knowledge to properly diagnose and treat birds. If you are struggling to find a good avian veterinarian you can consult the SEC for names and addresses. It would go too far to go into more detail about illness and healing in this paragraph. If you notice any abnormal behavior in your birds, we recommend that you buy the SEC booklet on "nutrition and health." This booklet has been written in collaboration with a number of veterinarians who are experts in the field of birds. For more information, please visit the SEC's website.