Case Study: Aspergillosis & Trichomonosis (Canker)

Eight years ago, Juliet’s community garden group decided to get chickens with each member responsible for an aspect of their care. They currently have 21 laying hens that are between 1-8 years old. “Taking care of those chickens gave me a false sense of how easy it would be to have my own. Those chickens rarely get sick.”

She built her first coop and got 3 one-week old and 2 four-week old chicks from a local breeder on May 16th.

Six days later, one of them, Pirate, was gaping (open mouthed breathing), but the symptoms went away only to return eight days later. On May 25th, a second chick (Jellybean) had died suddenly with no symptoms.

Gaping is a symptom of a variety of respiratory infections as well as gapeworm. Juliet treated them for the latter with Fenbendazole (Panacur, Safeguard) and holistic remedies like garlic, herbs, Colloidal Silver and Oil of Oregano. They intermittently got better, then worse.

The gaping improved and, thinking their illness was resolved, Juliet got three 4 week-old Black Copper Marans pullets from another breeder.

Then Popcorn, one of the original chicks and Bokeh, a new one subsequently became sick. Their most obvious symptom was gaping, followed by decreased appetite, not drinking and lethargy. At the end they had trouble standing and mucous discharge from their nares (nostrils).

By mid-June Pirate, a 4 week old Easter Egger had died and then a week later, Bokeh followed. Popcorn recovered and the two older chicks were never affected.

Juliet didn’t get a necropsy performed on Jellybean, the first chick, who died suddenly, but did for the following two and was kind enough to share the results of their diagnoses with me. Here is Pirate’s necropsy report:

A thick caseous material is present on the surface of the oral mucosa that extends into the esophagus and also involves the glottis.

Large numbers of flagellated protozoa are observed on wet mounts of scrapings of the oral mucosa consistent with Trichomonas gallinae.

The trachea contains excess mucus.

No gapeworms are present within the trachea. Numerous small white nodules are present in both lungs and the anterior air sacs consistent with granulomas caused by Aspergillus species.

A large white nodule is present the left caudal air sac at the opening of the recurrent bronchus. Moderate fibrinous airsacculitis is also present in the caudal air sacs.

The bird has severe breast muscle atrophy and weighs 108 grams.

Intestinal and cecal scrapings are negative for parasites and coccidia.
No lesions are noted in any other tissue or organ system.

Surprisingly, although Bokeh displayed similar symptoms as Pirate her necropsy revealed a different cause of death: mucoid sinusitis, bacterial polyserositis (inflammation of the membranes around the heart, lungs and abdomen) and pneumonia. There was no mention of aspergillosis or canker.

She had a chronic bacterial infection likely caused E. coli, a common secondary bacterial infection that can be lethal, particularly in young birds. The sinusitis could be due to Mycoplasmosis that could have been a mild primary infection that made the bird more susceptible to the secondary bacterial infection. – Dr Ficken, DVM

In speaking with her vet Juliet was advised that Aspergillosis is often caused by wet shavings which is a perfect environment for mold. She found out that other chicken keepers got sick chicks from the same breeder. I suspect that the breeder of Juliet’s chicks was the source of their illness.

What is Aspergillosis?

Aspergillosis, a fungal disease seen world-wide infecting both people and animals, is caused by inhaling Aspergillus fungi (mold).

The spores might be found in contaminated feed, moldy bedding, poop, soil or damp places within the coop. The fungi can penetrate eggs and infect the chicks, and if the eggs are broken they can release spores inside the incubator. If the hatchery is the source of the infection it is termed ‘brooder pneumonia’.

Once inside the body it may affect various systems, but is most often seen as a lower respiratory tract illness. Like many other pathogens, aspergillus is commonly found throughout the environment and can exist in low numbers without causing any harm. Sick or stressed birds are always more vulnerable to infection. Read more here.

What is Canker?

Avian Trichomonosis, often called canker (and not to be confused with ear canker) is a disease caused by one-celled protozoa, mostly affecting young birds. It primarily affects the chicken’s upper gastrointestinal system and causes them to develop lesions, or cankers, inside the mouth and the esophagus. As the disease progresses, the lesions get bigger and often interfere with the chicken’s ability to eat and drink. In severe cases, the lesions might block the esophagus causing suffocation. Read more here.

Credits: Necropsy photos and report: Dr Ficken, DVM (Texas A&M Veterinary Medical Diagnostic Laboratory); Juliet Morgan: case notes, photos and video. All material used with permission.

Featured Image: Microscopic view of Aspergillus Fungi (Credit: Biomedical Scientist)