Ever wonder how the chicken respiratory system works?
I mean, do chickens breathe the same as humans do? Are respiratory issues common with poultry?
The chicken respiratory system is a sophisticated mechanism that differs from our own.
In this blog, we will cover the following:
- Anatomy of the chicken respiratory system
- Common respiratory issues and their prevention, treatment, and symptoms
- Other ways to keep your flock’s overall respiratory health in good condition
The Anatomy of the Chicken Respiratory System
Understanding how the chicken respiratory system operates is a huge benefit for poultry farmers and backyard keepers alike.
This helps you take better care of your chickens while ensuring they stay healthy and can help you act fast if any issues arise.
Here are the basics of the chicken respiratory system and how it works.
Glottis
The glottis is a slit-like opening in the chicken’s trachea near the base of the tongue. It’s the entrance to the chicken’s respiratory system.
The glottis is a dynamic structure with flexible cartilage and muscles that give the chicken precise control over its aperture (the opening and closing) of respiration.
Beyond its respiratory role, the glottis is a key player in the chicken’s vocalization.
By modulating the size and tension of the glottal opening, chickens can produce diverse vocalizations, from content clucks to assertive cackles.
Larynx
Some people use the larynx and glottis interchangeably, but the larynx is situated within the trachea, right behind the glottis.
The chicken’s larynx is a specialized structure composed of cartilage, muscles, and connective tissues.
Unlike mammals, where the larynx is prominent in the neck, the avian larynx is a discreet yet essential component nestled along the trachea.
During inhalation, the laryngeal muscles relax, allowing air to flow freely into the trachea and into the rest of the respiratory system.
Conversely, during exhalation, these muscles contract, controlling the release of air and maintaining a balance that supports efficient gas exchange in the avian respiratory system.
Trachea
The trachea, commonly known as the windpipe, is the central airway passage connecting the external environment to the lungs.
The trachea is a rigid tube composed of cartilaginous rings, providing structural support and preventing collapse during breathing.
There is mucus inside the trachea, which acts as an inner lining that traps dust and other particles from entering the lungs.
Also inside the trachea lining are ‘ciliated epithelium.’
Basically, these are tiny little hair-like structures that remove the mucus and debris, which helps the chicken breathe easier and avoid infections.
At the bottom of the trachea is the syrinx.
This is where the trachea splits into two tubes, called the bronchi or bronchus (one is called a bronchus, and two are called the bronchi).
Bronchi
Connected to the lower end of the trachea, the bronchi make up the next segment of the respiratory pathway.
They extend into the lungs, forming a branching network that facilitates air distribution.
- Primary and Secondary Bronchi: The primary bronchi branch into secondary bronchi, ensuring that air reaches all parts of the lungs.
- Smooth Muscle Tissue: The bronchi contain smooth muscle tissue, allowing controlled dilation and constriction to regulate airflow.
Each bronchus is attached to and enters a lung.
Lungs
Like humans, chickens have two lungs. But unlike humans and other mammals, chickens have incomplete diaphragms.
Their sternum and chest muscles don’t allow for any expansion.
Because of this, the lungs are attached to the ribs, and the chicken’s lungs contain parabronchi (different from mammal alveolus).
These parabronchi are tubular and thin-walled, forming a complex network throughout the lung tissue. They’re also highly vascularized, with a lot of blood vessels.
The primary function of parabronchi is to facilitate gas exchange between the respiratory and circulatory systems.
Oxygenated air flows over the parabronchi during inhalation, and the thin walls allow oxygen to diffuse into the bloodstream.
Simultaneously, carbon dioxide, a waste product of metabolism, moves from the blood into the parabronchi to be expelled during exhalation.
Fresh, oxygen-rich air moves continuously in one direction over the parabronchi, ensuring a constant supply of oxygen for optimal gas exchange.
The efficient gas exchange provided by the parabronchi enables birds to extract oxygen from the air more effectively than in mammalian lungs.
This is extremely beneficial for lying birds but less helpful for chickens.
How The Respiratory System Works in Chickens
Basically, chickens have a dynamic respiratory system that involves both the inhalation and exhalation of air in every breath.
The respiratory system in chickens works by bringing in fresh air, storing it in air sacs, sending it to the lungs where oxygen is taken in and carbon dioxide is removed, and then exhaling the used air.
Here is more detail:
- Chickens breathe in air through their beaks or nostrils.
- The air travels down a tube called the trachea, which is like a highway for air in the body.
- The trachea connects to small air sacs in the chicken’s body.
- These air sacs act like storage bags for fresh air.
- From the air sacs, the air moves into tiny tubes called parabronchi in the lungs.
- The lungs are where the chicken’s body gets the oxygen it needs.
- In the parabronchi, oxygen from the air moves into the chicken’s blood.
- At the same time, carbon dioxide (a waste product) from the blood moves into the air in the parabronchi.
- The used air, now with less oxygen and more carbon dioxide, moves back through the trachea and out of the chicken’s body when it breathes out.
- Chickens have a cool system where the air moves through their respiratory system in one direction, keeping things super efficient.
- This continuous process ensures a constant supply of oxygen for the chicken’s body to stay healthy and active.
Common Respiratory Issues in Chickens
Here are some of the most common issues in chickens, plus their symptoms, prevention, and treatment.
Infectious Bronchitis
Infectious Bronchitis (IB) is a highly contagious viral respiratory disease affecting chickens worldwide.
It primarily targets the respiratory and reproductive systems, causing considerable economic losses in poultry farming.
Symptoms of Infectious Bronchitis
- Sneezing and coughing
- Watery eyes and nasal discharge
- Decreased egg production and quality
- Depressed appetite and slowed growth in young chickens
Prevention and Treatment
- Vaccination is a crucial preventive measure
- Strict biosecurity practices to prevent the introduction of the virus (this is covered in better depth in the below section)
- Supportive care, such as providing a warm and dry environment
Mycoplasma Gallisepticum
Mycoplasma Gallisepticum (MG) is a nasty bacterial infection that primarily affects the respiratory and ocular systems of chickens.
It can lead to chronic respiratory issues and severely impact overall flock health.
Symptoms of Mycoplasma Gallisepticum
- Coughing and sneezing
- Swollen sinuses and watery eyes
- Reduced egg production and fertility
- Blue discoloration of the comb and wattles
Prevention and Treatment
- Biosecurity measures to prevent the introduction of infected birds
- Antibiotics can be used for treatment, but complete recovery is often challenging
- Culling of severely affected birds to prevent the spread of the disease
Aspergillosis
Aspergillosis is a fungal infection caused by the inhalation of spores from the Aspergillus species.
Chickens are susceptible, especially in environments with high humidity and poor ventilation.
We covered an article on Aspergillosis in ducks, which you may also find helpful.
Symptoms of Aspergillosis in Chickens
- Labored breathing and gasping
- Coughing and sneezing
- Reduced activity and weight loss
- White or yellow nodules in the respiratory tract during post-mortem examination
Prevention and Treatment
- Improving ventilation and reducing humidity in the coop
- Proper cleaning and disinfection practices
- Antifungal medications for treatment, although success can vary depending on the severity of the infection
Newcastle Disease
Newcastle Disease (ND) is a highly contagious viral infection that poses a significant threat to poultry, including chickens.
Named after an outbreak in Newcastle, England, in 1927, this disease affects various bird species, causing respiratory, digestive, and nervous system symptoms.
Newcastle Disease is endemic in many parts of the world, causing ongoing challenges for poultry producers.
Understanding Newcastle Disease is essential for poultry farmers to implement effective prevention and control measures.
Symptoms of Newcastle Disease
- Sneezing, coughing, and nasal discharge
- Labored breathing and gasping
- Swelling around the eyes and neck
- Diarrhea
- Reduced egg production and quality
- Twisting of the neck (torticollis)
- Paralysis and uncoordinated movements
Prevention and Treatment
- Vaccinations. Regular vaccination is a cornerstone of Newcastle Disease prevention. Vaccines are available in various forms, including live and inactivated.
- Strong biosecurity measures. Strict biosecurity protocols help prevent the introduction and spread of the virus. We cover this in detail in another section below.
- Cleaning and Disinfection. Regular cleaning and disinfection of facilities and equipment help eliminate viral particles.
How to Maintain a Healthy Chicken Respiratory System
So now that you understand how their body works and which ailments are the most common, let’s get into the details of how exactly you can keep your chickens safe.
Proper Ventilation in Chicken Coops
Proper ventilation will prevent so many issues in your flock.
But we hear so often that a draft, especially in the winter, is bad for chickens. So what’s the difference?
Ventilation is usually intentional and controlled to maintain a healthy environment.
Drafts are more often unintentional and uncontrolled, potentially causing discomfort or stress to the chickens.
Ventilation aims to improve air quality by regulating temperature, humidity, and gas levels.
Drafts are generally considered undesirable as they can create pockets of cold or turbulent air.
Ventilation should be at the top of the coop. This is where the most toxic gases like ammonia float, so it’s where the ventilation should be.
It also allows humidity, other harmful gases, and some heat to escape the coop.
If you’re wondering which is more important, heat retention or ventilation, a lack of ventilation is far deadlier than a lack of heat in most situations and chicken coops.
The ventilation should also always be above your roosting bars. You do not want the ventilated air to blow directly onto your birds as they sleep.
Good Biosecurity Practices
Good biosecurity practices include quarantining new birds, quarantining birds who have left your property, even only temporarily, and making sure that you don’t contaminate your property with infected items, like shoes, gloves, or poultry equipment.
Knowing how to clean and disinfect your coop is a huge asset; you should do this at least once a year if you do not practice the deep litter method.
You should also clean and disinfect your coop after any disease or illness outbreak to prevent the spread of it.
Vaccination Protocols
Several vaccines are available to help prevent respiratory issues in chickens.
These vaccines are crucial for maintaining the health of your flock and preventing the spread of respiratory diseases.
Here are some common vaccines that target respiratory issues in chickens:
- Infectious Bronchitis (IB) Vaccine
- Newcastle Disease (ND) Vaccine
- Mycoplasma Gallisepticum (MG) Vaccine
- Infectious Laryngotracheitis (ILT) Vaccine
- Avian Influenza (AI) Vaccine
FAQ on the Chicken Respiratory System
What Are the Respiratory Issues in Chickens?
Respiratory issues in chickens can include Infectious Bronchitis, Mycoplasma Gallisepticum infection, and Aspergillosis.
These can manifest as symptoms like coughing, sneezing, nasal discharge, and labored breathing.
Good biosecurity, proper ventilation, and regular veterinary care are essential for preventing and managing respiratory issues.
What Do You Give Chickens for Respiratory?
Treatment for respiratory issues in chickens often involves veterinary consultation.
Antibiotics may be prescribed for bacterial infections, while antifungal medications may be used for fungal infections like Aspergillosis.
Supportive care, such as maintaining a clean and well-ventilated environment, is also crucial for recovery.
What Is The Function of the Trachea in a Chicken?
The trachea in a chicken serves as the main airway for breathing. It allows air to travel from the external environment to the respiratory system.
The trachea is lined with ciliated epithelium and mucous glands, which help filter impurities from the air.
It is a vital component of the chicken’s respiratory system, guiding air passage to and from the lungs.
The Chicken Respiratory System: Before You Go…
A chicken’s respiratory system is similar but not equal to a human’s, which poses different challenges to keeping it healthy.
Our best advice for maintaining your flock’s respiratory system is to maintain a clean, dust-free coop and run, vaccinate your birds accordingly, and maintain strong biosecurity practices on your property.
Of course, keeping yourself educated on how the chicken body works, as you’re doing here, will do a lot to help you maintain your flock’s health and well-being.
