Chickens have extremely good daytime vision but poor nighttime vision. In fact, chickens rely on their sense of sight more than other senses to conduct their daily business.
Untreated eye problems and infections can easily lead to the death of a chicken and spread among the flock, not to mention often being painful.
Table of Contents
- What should healthy chickens eyes look like?
- A little about the biology of a chickens eyes:
- What cause eye problems in chickens?
- Symptoms of eye problems in chickens and their probable cause:
- Can chickens survive blindness in one or both eyes?
- How do you treat chickens with eye problems?
- Large white lumps in the eyes:
- Why a chickens eyes swell shut?
- Why is my chicken's eye foaming?
- Chickens eye losing colour:
- Cloudy eyes in chickens?
- Eye missing in chickens
- Problems with the eyelids in chickens:
- Eye worms in chickens:
I notice quickly when my chickens have impaired vision and aren’t able to find food, navigate the coop, or avoid bullies.
Some chicken eye problems are simple to diagnose and treat and seem to heal quickly while others are caused by serious diseases. If you are unsure about what the problem is with your chickens eyes then you should consult a professional.
What should healthy chickens eyes look like?
Healthy chicken eyes are clear and bright with no swelling or discharge. The features of the eye like the Iris and the pupil should be round with even edges and good colour. Eyelids should be a even concave shape and move freely.
The third eyelid or nictitating membrane is used to keep the eye clean and should flick regularly across the eyeball.
Below: A example of a healthy chickens eye.
Chickens can see the smallest morsels of food during the day but as the light begins to fade, so does their sight. This is the clue for them to begin to roost.
A little about the biology of a chickens eyes:
Chickens have two eyes on either side of the head giving them good all round vision, essential if you are near the bottom of the food chain. This enable them to see almost all around them as well as above their heads and large area of ground.
Chickens can have a sleeping state called "uni-hemispheric sleep", in which one half of the brain is awake and the other is sleeping. If you have ever encountered a healthy chicken resting in the sunshine with one eye closed and one open, they are sleeping one side of their brain.
Below: You can see the third eyelid working on this Jubilee Orpington.
Chickens have three eyelids, the top, the bottom and the nictitating membrane which cleans the surface of the eyeball.
What cause eye problems in chickens?
Disease, foreign bodies, parasites, injury, poisons and genetic factors all cause problems with the eyes of chickens.
A list of conditions that affect a chickens eyes:
- Fowlpox. Sometimes called Avian pox, it causes heavy blistering on the heads of infected birds that can interfere with the eyes.
- Marek's causes swelling and tumours in the nervous system and can effect eyesight.
- Infectious Coryza is a common bacterial infection of backyard chickens.
- Mycoplasma infections are a leading cause of bubbles in the eyes of chickens.
- Injury from fighting or predator attacks can cause temporary or permanent blindness
- Aspergillosis and fungal infections.
- Foreign objects like dust or grit can get into the eye and scratch the surface of the cornea.
- Blindness has a wide variety of causes.
- Conjunctivitis can be a symptom of another condition or exist on its own.
- Parasites and worms.
- Genetic deformities.
- Poisons like formic acid from ants.
- Irritants like dust or pollen. Iris flower pollen is poisonous.
- Stings from plants or animals. Stinging nettles and poison ivy can affect chickens.
- Stroke can cause nervous problems and often a chicken will be unable to open one eye.
Until you know the cause of the eye problem in your chickens you should isolate the bird to prevent spreading and make treatment easier.
Symptoms of eye problems in chickens and their probable cause:
Looking for the following symptoms in your chickens will tell you whether they have eye problems:
- Swelling in or around the eye.
- Bubbles in the eye.
- Pus or discharge from the eye.
- One or both eyes closed.
- Yellow plaques under the eye lids.
- Scratched corneas.
- Bleeding in or around the eye.
- Conjunctivitis or inflammation.
- Dull expression of the eyes.
- Lesions on or around the eyes.
- Blisters from stings.
- Cancerous tumours.
- Odd shaped pupils or iris.
- Loss of colour of grey eyes.
Below: Here is a Sebright bantam with eye problems.
Can chickens survive blindness in one or both eyes?
One of the advantages of living in a flock is that there are many pairs of eyes to keep a look our for danger.
Chickens can live happily with only one eye and can find food, drink and scratch without any problems. Although it is much more difficult and time consuming for the chicken and for you, even completely blind chickens can survive once they have learned where everything is in their environment.
A chicken with one eye may still be able to roost but a blind bird will not. You should provide a chicken ladder for the visually impaired.
A blind and handicapped chicken is likely to be bullied to the bottom position of the pecking order.
How to treat a blind chicken depends on what is causing the blindness. With injury, time is the best healer and with other condition sight should return in time if the original disease is treated properly.
Chickens recover well from missing eyes, I have had this among fighting cockerels twice in my time as a keeper.
How do you treat chickens with eye problems?
Any chicken with a suspected eye problem or infection should be removed from the flock and isolated immediately.
Below: Eye problem need to be treated quickly.
Treat eye disease in chickens means medicating for the underlying complaint and the chicken may need testing to decide whether the infection is bacterial or viral.
Treatment of an eye infection in a chickens often requires other supportive treatments like bathing the eyes regularly in sterile warm water.
You can produce this by boiling the water and allowing it to cool to 40 Celsius or 104 Fahrenheit. Add a teaspoon of salt if you require saline.
Large white lumps in the eyes:
The large Whitish or yellow lumps of hard pus found under the eyelids of chickens are a result of infection by Mycoplasma gallisepticum or Infectious Coryza.
Below: The white solid lump in the eye of a chicken.
These white lumps have to be remove from the eyes although small amounts will fall out in their own time.
Pus can be removed from a chickens eye more easily after the infection has been treated.
It is easier if you use eye drop to lubricate the eye before you try. Use sterile warm water to loosen the pus and aid in the removal of the pus. It may take a few attempts over a few days and you can find a graphic video on YouTube to help.
Why a chickens eyes swell shut?
Infectious Coryza causes swelling of the face in chickens and it can look like one or both sides of the head is bulging outwards. Coryza is accompanied by a foul smelling discharge that can matt the feathers.
Below: The classic swelling of Infectious Coryza. In the old days this was called swollen head disease and you can see how it got it's name.
The chicken can't open one or both eyes and the eyelids appear top be stuck closed, especially in the mornings.
Chickens with one or both eyes closed may also appear lethargic and nor move much.
Infectious Coryza is a painful condition that requires treatment with antibiotics.
Why is my chicken's eye foaming?
A chicken with bubbles in it eye is suffering either from Mycoplasmosis, an infectious disease caused by the Mycoplasma gallisepticum bacteria or Infectious Coryza.
With Mycolplasma infection the bubbles are thin and watery and there is generally little or no swelling of the eye and with Infectious Coryza the bubbles are firmer and there is likely to be swelling around the eye and the discharge has a bad smell.
Below: A chicken with bubbles in it's eyes.
Both Mycoplasma and Coryza are bacterial in origin and require treatment with antibiotics like Tylan for which you may need a prescription from a veterinarian. Neither of these conditions will get better on their own without treatment.
The chickens eyes may stuck closed, especially in the mornings and complimentary treatments include washing the eyes with warm sterile water
Topical eye drops for chickens can be purchased to bring relief and speed healing.
Chickens eye losing colour:
Marek's disease is the almost certain cause of chickens eyes going Gray or losing colour. It is called ocular Marek's and has no treatment.
Marek’s Disease is a highly contagious tumour causing viral infection which affects chickens and rarely affects the eyes.
Mortality from this type of infection is around 25% and blindness or partial blindness is common in survivors.
Cloudy eyes in chickens?
An eye that is cloudy in chickens generally means the chicken is blind in that eye. Infection can cause the third eyelid to remain closed giving the eyes a cloudy appearance.
Below: This is what a cloudy eye looks like in a chicken.
Cloudy eyes in chickens are caused by cataracts, infection or injury and the result is usually permanent.
There is no treatment for cataracts in chickens. An injury may heal and the sight may return, if only partially and if the underlying infection is treated some sight may be restored.
Eye missing in chickens
I have twice seen eyes missing from chickens. On both occasions it was fighting cockerels that lost an eye.
A chicken can withstand losing an eye as long as it does not get infected. The eye socket will heal up and close over quite quickly and the eye stalk will shrivel up and drop off.
Problems with the eyelids in chickens:
A stroke, nerve damage, Mareks disease or injury can cause eyelid problems. The chicken may be unable to open the eyelids properly or at all and one or both eyes may be affected.
Make sure it is not conjunctivitis causing swelling and treat appropriately.
There is no direct treatment for any of these conditions, other than time, and it will either recover or not. Supportive treatments can be given such as lubricants and drops.
Eye worms in chickens:
The disease known as Manson’s eye worm is caused by a nematode that is a type of roundworm.
Chicken eye worms look like very tiny earthworms and are part of the same family. They can be seen moving around between the membranes of the eye if you look carefully.
Conjunctivitis is also known as Pink Eye and is the inflammation of the conjunctiva, which are the delicate membranes of the inner eyelid. Conjunctivitis can occur in one or both eyes and may be a symptom of another condition or may be an infection of its own.
Conjunctivitis is a localised swelling of the eye and tissues around the eye and is characterised by redness and puffiness.
Conjunctivitis may be caused by:
- Bacterial, viral, or fungal infection.
- Parasites like eye worms.
- Exposure to foreign bodies like sand, dust, feather dander or pollen.
- Exposure to physical irritants like ammonia, smoke or chemicals.
Treatment of Conjunctivitis in chickens is with eye drops.