3 Killers among us
Aspergillus, Staphylococcus Aureus, E. Coli
They are among us every day, often without us even knowing it. They live on our skin, in the soil, and all around us. It's not until we get a small cut or have a compromised immune system that they can cause harm. I learned the hard way that these silent killers are far too common among our birds.
STAPHYLOCOCCUS AUREUS
Staphyloccosis
This bacteria plays a role in helping both birds and humans develop resistance to other diseases. It resides on the skin or mucus membranes. However, if it gains an entry point into the body—such as through a cut—it can cause devastating damage. Bumblefoot, one of the most common ailments in poultry, is a leading cause of staphylococcus infections.
A healthy individual is generally not affected by the Staph bacteria. In most cases, it's clear that the individual had a weakened immune system for one reason or another, which lowers the body's defense against the bacteria.
The bacteria can also spread from an infected individual during mating.
When the bacteria enter the bloodstream, it becomes deadly, leading to a condition known as sepsis.
The incubation period for the bacteria is typically 1–3 days, with progression to the acute form (sepsis) occurring within about one week. The chronic form, however, can take up to 5 weeks to develop.
The symptoms of a Staph infection can often be mistaken for Fowl Cholera, as they are quite similar. During necropsy, you may find digestive fluid in the digestive tract and a dark, swollen liver.
Dumptruck, Indian Runner duck
3 years old
It all went so fast. When he first started showing symptoms, it only took a few days before he passed. It began with him avoiding the flock, then lying down more and more. He stopped eating, and when I weighed him, I saw that he had lost 400 grams in less than a month. On the same day he passed, he lost the ability to walk. Later that evening, as I picked him up, he seemed to finally relax — and he passed away in my arms.
I had him sent for a necropsy, which revealed just how much havoc had been wreaked on his body. He had lesions everywhere. A bacterial culture confirmed the cause as Staphylococcus aureus, and most likely he had gone septic, since everything progressed so quickly.
Dumptruck had suffered an eye infection within his first year of life, caused by bacteria already present in his own system. This had suggested even back then that he likely had a weak immune system all along, making him especially vulnerable to a severe staph infection.
ASPERGILLUS
Aspergillosis
A fungus that lives on decaying organic matter surrounds us every day. It is so common in both our birds' environment and our own that it is nearly impossible to fully prevent or eliminate.
Aspergillosis is most commonly caused by Aspergillus fumigatus, but it can also be caused by other fungal species.
Both birds and humans can become sick if they inhale spores from decaying litter. However, it rarely affects healthy individuals with a strong immune system. It is when the immune system is weakened that this fungus becomes dangerous. It causes pneumonia which, without fast and correct treatment, can be deadly. The disease is difficult to diagnose because symptoms take a long time to appear — and by the time they do, the infection has often been present for a while.
In embryos, infection can sometimes be seen already inside the egg: when candling, the egg may show a greenish appearance if affected by aspergillus. Newly hatched chicks may display symptoms such as gasping, swollen eyes with yellow fluid, and discharge from the eyes and nose.
There are two forms of aspergillosis:
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Acute aspergillosis (also called brooder pneumonia) is the more common form. It has an incubation period of 2–5 days and carries a mortality rate of around 10%.
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Chronic aspergillosis (also called bronchomycosis) is less common. It develops over several months before symptoms appear and has a lower mortality rate, around 5%.
Aspergillosis does not spread directly from bird to bird.
Why does aspergillosis occur?
Spores of Aspergillus fumigatus and related fungi live naturally in the environment of birds and poultry. They thrive in damp conditions, especially around feeders, water stations, and even inside them.
How can I prevent it?
If you experience recurrent cases of aspergillosis, review your ventilation system. Maintaining a dry setup is key. Regularly disinfect water containers and feeding stations (a 1% Virkon solution is very effective).
Aspergillosis has no true cure, but it can sometimes be managed with antifungal medication. However, these drugs are often very harsh on the body, highly toxic, and come with many side effects. Deciding to treat should therefore involve weighing the pros and cons carefully. Unfortunately, the market lacks effective antifungal medications for birds.
A necropsy will typically reveal mold growth in the trachea, fluid in the abdominal cavity (water belly), and cheesy nodules in the lungs and air sacs. The lungs will appear greyish-yellow in color.
Panic, Silkie Chicken
6 months old
Panic was a cross-beak Silkie rooster. He had a rough start in life due to his cross beak, and later developed severe scoliosis. He was only half the size of a normal Silkie rooster, which showed that something in his system was not functioning properly.
It began with him losing weight and having a lot of air in his crop (at first, I suspected sour crop). He lost weight so quickly, and despite tube-feeding him, he was unable to gain anything from the food. Being so small to begin with, he simply didn't have much reserve to lose. His condition declined rapidly, and the weekend before he passed, he began gasping heavily.
Because he was so tiny, the vet could not even test him for aspergillosis — he didn't have enough blood. And even if the test had been positive, he would not have survived the medication, as his kidneys were already too weak to handle it.
I could see in his eyes that he could not go on. He was allowed to pass peacefully at the vet's office, next to me and one of his flock mates, knowing he was deeply loved.
Looking back and researching for this article, I am fairly certain that Panic had the chronic form of aspergillosis and was already infected when he arrived here.
E. COLI
Colibacillosis
Also called coliform infection, this disease is caused by the bacterium Escherichia coli.
The symptoms vary widely and are often complex. How susceptible a bird is depends on the bacterial strain as well as the age and condition of the bird.
Some possible symptoms include:
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Sepsis
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Airsacculitis
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Pericarditis
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Blindness in one eye while otherwise appearing healthy
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Swollen leg joints with yellow fluid
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Yellow, watery droppings
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Laying hens may stand with an upright posture and often die within six months (egg peritonitis)
In different age groups:
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Newly hatched chicks: death within 6 days, often with a swollen navel and foul odor.
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Growing birds: lameness, lethargy, fever, and swollen joints.
Just like Staphylococcus, E. coli needs an entry point before it can wreak havoc in the body. The most common entry points are:
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The respiratory tract
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Skin wounds
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The cloaca
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The mucous membranes of the digestive tract
The bacteria can cause a wide range of symptoms on their own but are also commonly seen in combination with other infections, such as respiratory diseases, infectious bronchitis, infectious synovitis, or Newcastle disease. The severity of colibacillosis can range from acute to mild to chronic.
Why does colibacillosis occur?
E. coli naturally exists in the bird's environment and typically only affects individuals with a weakened immune system, or it appears as a secondary infection. Most often, the bacteria are picked up from a reservoir such as fecal matter, contaminated soil, water, or food. Infection may come directly from a flock mate, but also from wild birds, mammals, beetles, or even common houseflies.
How can I prevent colibacillosis?
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Maintain good hygiene and proper ventilation.
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Regularly clean and disinfect water containers and feeders.
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Prevent rodents and pests from accessing feed and housing.
Treatment:
Colibacillosis can be difficult to treat. Infected birds should be kept in a clean, warm environment, given a high-protein diet, and supplemented with vitamin E. Antibiotics can be effective if given early in the course of the infection.
Professor Ratigan "Poppi", Silkie Chicken
3 years old
In the end, it was her own body that destoyed her. It started as a classic sour crop case, it was treated for a long time as sour crop with not ever getting better. She did first test negative for any infection, but later we found out that this was a false negative. Her body has created barriers around the infection, abcesses started to appear everywhere in her body and one of them was place right in her esphagous. Despite being on the right antibiotic the infection did not respond to it. Due to the barriers around the infections, the antibiotics could not do its work.
The infection spread fast in her last 7 days, making it hard for her to breathe. Despite all this she still free ranged and seemed healthy. In the end, when we saw the Xray, we know she would only get worse. We could wait until this time came, but in the end we decided to let her pass with dignity.
Poppi had never laid an egg normally. She was on the suprelorin implant for the most of her life. This makes me wonder if something was going on in her body from the start that did weakend her immunsystem, making her get this infection.