Red appearing eyes in pet birds are usually due to inflammation of the conjunctiva (mucous membrane surrounding the orbit), the nictitating membrane (third eyelid) or the eyelids. Some species of birds have a red-pigmented iris and therefore normally have a red eye.
It is common for birds to have reddening of the eyes or surrounding structures alone with no other symptoms. This is especially true of cockatiels. Birds with inflammation of the eyes or surrounding structures, however, may have also have an ocular discharge. And, since the sinuses are intimately associated with the eye, many birds will also have symptoms of upper respiratory tract disease, such as sneezing or nasal discharge.
Your veterinarian will recommend specific diagnostic tests depending on how severe the symptoms are or how long the problem has been going on. Chronic or recurrent redness to the eye or redness accompanied by signs of respiratory disease may require extensive diagnostic testing. Occasionally, irritants from the environment (dust or chemicals) may cause a temporary reddening of the conjunctiva or lids. If the redness persists for over 24 hours, or if other symptoms are present, veterinary attention is necessary.
What to Watch For
Your veterinarian will recommend specific diagnostic tests depending on how severe the symptoms are or how long the problem has been going on. Chronic or recurrent redness to the eye or redness accompanied by signs of respiratory disease may require extensive diagnostic testing.
A complete history is extremely helpful in reaching a diagnosis. Be prepared to tell your veterinarian the following:
Treatment may include any of the following:
Bird showing severe symptoms, especially difficulty breathing, lethargy or loss of appetite may require hospitalization for 24-hour care.
If your bird has an increased redness to the eyes and has no other symptoms, you can do the following:
After seeing the veterinarian, be sure to give all medication as directed, for as long as directed, even after the symptoms appear to be gone.
If improvement is not seen, report this to your veterinarian. If the redness is worsening or the bird develops other symptoms, alert your veterinarian immediately.
Avian eyes and surrounding structures differ from those of mammals in several ways. The sense of sight is extremely well developed in birds; therefore the globe (eyeball) itself is significantly larger than that of equivalent sized mammal. The iris is also much larger, filling the entire area of the open eyelids; the sclera, or white portion of the globe visible outside of the iris, is not normally visible. The iris is highly pigmented. In some species of birds, the iris is pigmented with a red or red-brown color, and in these species, a red eye is normal, as long as it is just the iris that appears red.
Often, a mammal's eye will appear red when blood vessels are engorged and visible in the sclera, what we call "blood-shot" eyes. Since the sclera is not normally visible in birds, this is not a common cause of red eye.
Most birds with red eyes have inflammation of the conjunctiva (mucous membrane surrounding the globe), nictitating membrane (third eyelid) or the eyelids themselves. When the nictitating membrane closes, it moves from the upper half of the medial canthus (area of the eye closest to the beak) toward the lower, outside portion of the eye (lateral canthus). If swelling and redness of the nictitating membrane occurs, the red coloration will appear in the medial canthus.
Redness and swelling of the conjunctiva can appear around the circumference of the eye, although it is usually most noticeable on the lower eyelid margin. In pet birds, the lower eyelid moves up when the eye closes. Swelling and redness of the eyelids are also common. These birds usually appear to be in pain, and may hold the affected eye closed.
The avian skull is full of air pockets or sinuses. These sinuses reduce the overall weight of the skull – a necessary adaptation for flight. The sinuses connect with the nasal passages and extend completely around the eyes. Because of this connection, respiratory infections often extend into the sinusitis and periocular tissues. Birds with sinusitis often have swelling surrounding the eyes, due to inflammation of the sinus wall or because the sinus itself is full of exudate (pus). If large amounts of exudate accumulate, the eye may actually be pushed forward, bulging out from the skull.
Inside of the globe itself is a vascular structure, called the pecten, which supplies nutrients to the retina. The pectin is not visible without specialized magnification, because it is located behind the iris. Severe trauma to the globe or infection within the globe itself (inside the eyeball) may cause bleeding within the globe (intraocular hemorrhage). Intraocular hemorrhage is termed hyphema and appears as a solid red eyeball, with no visible pupil.
Inflammation of the conjunctiva may occur due to environmental irritants, such as dust, aerosol sprays or smoke. Birds are extremely sensitive to cigarette smoke, and smoking around birds should be avoided at all times. If possible, eliminate the amount of dust the bird is exposed to. If ocular redness persists for over 24 hours, or if other symptoms are present, veterinary attention is necessary.
Causes of Red Eye
The severity of red discoloration and which portion of the eye affected will vary with the cause. Hyphema is caused by trauma or infection within the eye. Environmental irritants or infectious agents may cause conjunctivitis or eyelid swelling. Conjunctivitis with eyelid swelling and bulging of the eye is usually secondary to sinus disease or tumors.
Possible causes of red eyes include:
A thorough history is an essential component of the diagnosis. Your veterinarian will probably ask you the following questions:
Your veterinarian will recommend specific diagnostic tests depending on how severe the symptoms are or how long the problem has been going on. Chronic or recurrent ocular disease may require extensive diagnostic testing. Any combination of the following may be recommended:
There are many causes of red appearing eyes and the cause must be identified for proper treatment. Diseases that can cause severe destruction of the eye and/or sinuses, such as Aspergillosis, many bacterial infections or neoplasia (cancer) will require hospitalization and extensive, long term treatment. On the other hand, birds with eye disease and no other symptoms can be treated on an outpatient basis.
Until diagnosis has been completed, treatment of symptoms might be needed, especially if the problem is severe. The following treatments may be applicable to some, but not all birds with red eyes. These treatments may reduce severity of symptoms or provide relief for your pet:
For mild conjunctival irritation and to prevent future problems, the environment may be modified by: