The Rabbit’s Eye
This article is about the Rabbit’s Eye, including vision, health, problems and possible treatment. A Rabbit’s vision is one of its most important senses. In the wild they rely on it heavily to spot danger.
The eyes are placed to the side and to the top of the narrow head of a Rabbit. They often appear slightly bulging and seem to give the impression of never blinking. But in reality they blink so fast as not to be noticed by the human eye. A Rabbit will blink as little as 12 times an hour.
Parts of the Eye
A Rabbit’s eye is called the Globe. It is positioned on a bony cup called the Orbit. A series of muscles are attached to the outside of the Globe which moves the Globe around. The eye is filled with a fluid which is continually being produced and drained so the amount of fluid is kept constant. The coloured part of the eye is a muscle known as the Iris. A central hole in the Iris called the Pupil is where the light passes through. The Pupil contracts and expands depending on the strength of the light source. Light comes through the Pupil, which passes through the Lens, which focuses the image. Muscles attached to the Lens allow it to change shape to focus on different things. This focused light from the Lens hits the Retina, which changes this light into nerve messages, which are sent to the brain through the Optic Nerve enabling the Rabbit to see images. The Tear Duct produces tears, which keep the eye lubricated. The Rabbit has a third eyelid called the Nictitating Membrane. This eyelid sits under the upper and lower lid. The membrane may be drawn half way across the eye in times of stress and fright. It also helps to keep the eye moist and protect against injury.
Basic diagram of the Eye
A Rabbit has a field of vision of almost 360-degrees and it can see well above its head. Enabling it to easily spot danger. They have a small blind spot directly in front of them and directly behind them. The eyes are designed for long-sighted use and have limited near vision. The Pupils have a limited contraction capacity therefore they see well in dim/dull conditions. Bright light restricts their vision and intense light can lead to temporary blindness. A Rabbit’s eye is eight times more sensitive to light then a human eye. Surprisingly Rabbits do not have good night vision. The eye does not have a Tapetum, the structure that acts to amplify light that has entered the eye. A Rabbit will see the world as a “grainy” picture. There is some debate as to whether or not Rabbits are colour blind. Some research suggests that they can see green, red and blue.
Problems of the Eye
Rabbits can have a variety of problems with their eyes. Below are some of the most common ones. By no means is this an extensive list. Remember if in doubt always seek Veterinary assistance.
Probably one of the most common problems with Rabbits eyes. A variety of things can cause runny/weeping eyes.
Allergies/Irritants such as dusty hay/bedding, household aerosols. Cigarette smoke, drafts, cold, high ammonia content in Urine due to a high protein diet, ingrown eye lash can all cause a Rabbit to have a clear discharge with excessive tear production from its eye. Obvious irritants should be eliminated. Check diet is not too high in protein. Try bathing the eye. If the condition persists after a 24 hours a trip to the Vet is in order.
Conjunctivitis can often be caused by an allergy or irritant. The Conjunctiva becomes red and sore. A clear or white discharge may be present. All possible irritants should be removed. A trip to the Vets is needed for antibiotic and/or anti-inflammatory eye drops.
Over-grown teeth can irritate and/or block the Tear Duct causing tears to run down the Rabbit’s face. A thick white discharge in the eye or eyes is a sign of Tear Duct infection. The eye may be matted/closed with the discharge. A visit to the Vets is necessary to check for teeth trouble. Antibiotic eye drops will probably be provided if an infection is present. Tear Duct flushing may be necessary in some cases.
Runny or weeping eyes should be bathed in cooled, boiled salted water to stop them getting matted and stuck together. Use a fresh piece of cotton wool every time you wipe. It may be an idea to put a dab of Vaseline under the Rabbits eye to stop the skin underneath getting sore form the constant dampness.
The surface of the Cornea can easily become damaged by knocks to the eye and foreign bodies scratching the surface. (Straw should be avoided as a bedding material at all costs, as it is very harsh and stiff. It easily gets poked in the eye). A scratch to the surface of the Cornea could cause an Ulcer to form. It will appear as a little pit on the surface of the eye and it may look cloudy. The Rabbit will probably have its eye half closed and will be showing some discomfort. A trip to the Vet is necessary for appropriate treatment.
A Cataract is when the Lens of the eye becomes white and cloudy. A Cataract can lead to blindness in the affected eye. They are painless and Rabbits cope well with them if they are kept in familiar surroundings. Treatment is rarely offered. Cataracts generally appear as part of the ageing process. They can sometimes appear if the eye has suffered a significant trauma.
Glaucoma is the name given to a condition where by the eye is not draining fluid properly and there is a build up causing the pressure in the eye to rise. The eye looks swollen and sore. Glaucoma is rare in Rabbits. Veterinary treatment is needed, usually eye drops.
This is when an abscess develops in the eye socket and pushes the eye outward. Giving a bulging/swollen appearance. A Tear Duct/Tooth Root infection or foreign body can cause this. Veterinary treatment is needed. A long course of antibiotics may solve the problem. Worst-case scenario may result in removal of the eye.
One of the first signs of the disease Myxomatosis is sore/swollen eyes and genitals. If you suspect your Rabbit has Myxomatosis seek Veterinary assistance IMMEDIATELY! Preventative methods include vaccinating and fly control.
This isn’t actual a health problem. It’s a behavioural trait some Rabbits will show. It’s when they rock or sway their head from side to side to get a better look at close up objects. More commonly seen in pink/red-eyed Rabbits. If your Rabbit is a scanner they will regularly do it. If your Rabbit has suddenly adopted this behaviour it may be a sign of a problem and a Vet trip is in order.
I hope you find the article useful. It gives you a basic outline on the Rabbit Eye. You can find more detailed information in the many books and websites there is on Rabbit’s.
Written by Louise Wood (ellepotter) 17th May 2005.
Keeping Rabbit’s, by Elisabeth Downing
Rabbit Lopaedia, by Meg Brown and Virginia Richardson
Dwarf Rabbit’s, by Monika Wegler
Living with a House-rabbit, by Linda Dykes and Helen Flack