Ocular discharge

Ocular discharge refers to discharge coming from the eyes. This can affect one or both eyes and any discharge originating from the eyes should be thoroughly assessed, as it may be a sign of ocular disease or underlying dental problems.

A guinea pig’s eyes should be bright and alert with no discharge. Looking from above the guinea pig they should be symmetrical with neither protruding more than the other. Either eye bulging is abnormal. Eyes being sunken or dull are signs of dehydration and illness; any of these signs or discharge from the eyes is abnormal and should be taken to a veterinarian for examination.

This depends upon the cause of the discharge. If there is no infection present, the discharge may be clear in colour (almost like tears). If there is infection it may be pus like and be white, yellow or even a green color. The discharge may be smelly too and thick in consistency. The fur around the eye will often matt together and may fall out, causing the skin to become red, sore and inflamed around the eye(s). This can be extremely painful for the guinea pig.

There are lots of reasons why a guinea pig may have discharge from one or both eyes. These include:

• Dust or foreign body within the eye: this usually affects only one eye.
• Corneal ulcer on the surface of the eye: normally only one eye is affected and is more common in guinea pigs since they like to burrow in bedding. Straw is a common reason for damage to the eye when it pokes into the eye.
• Entropion: this is where the eyelashes grow inwards and rub on the surface of the eye, causing irritation. It may affect one or both eyes and is often apparent from a young age.
• Bacterial infections: there are lots of bacterial infections which may cause ocular discharge.
• Blockage of the nasolacrimal duct due to dental disease: the nasolacrimal duct runs from the eyes to the nose and along the upper jaw. If the tooth roots overgrow and impinge upon the tear duct, they can cause a blockage, so the tears overflow in the eye as they cannot run down the tear duct to the nose.

Sometimes along with the discharge from one or both eyes, the guinea pig may have discharge from the nose, matted/missing fur around the eye(s) with red, sore and inflamed skin. If the guinea pig is suffering from dental disease, they may also hypersalivate and be off their food with some weight loss. Guinea pigs that are in pain may also eat less, be withdrawn and pass fewer/smaller droppings. These are all causes for concern and the guinea pig must see a veterinarian for prompt treatment.

Firstly, they will perform a thorough clinical examination, looking at the whole guinea pig and examining the guinea pig’s eye(s). They will look to see if there are any signs of a foreign body, such as a hay seed, or any ingrowing eyelashes.

They may place some fluorescein dye in the eye(s) to see if there are any corneal ulcers. If your veterinarian wants to see if there is an infection they may suggest taking a swab to send off for testing and to see what antibiotics may be best to use.

Dental disease will need to be diagnosed under sedation or general anesthetic with x-rays taken to assess the tooth roots. The guinea pig may need supportive treatment first to make the anesthesia safer by syringe feeding, fluid therapy, pain relief and prokinetic medication to keep the digestive system moving.

If the cause is a foreign body this will need to be removed which may require sedation or a general anesthetic. Entropion also requires surgery to remove the excess skin around the eyes so the eyelashes don’t rub against the eye, and again will require a general anesthetic.

Corneal ulcers may need to be removed to encourage healing, as well as prescribing eye medication. Removal is normally carried out under sedation and involves the surgical removal of a section or layer of the cornea to encourage the ulcer to heal. Infections will require antibiotics.

Dental disease requires general anesthesia to assess the teeth properly and perform a dental, this will often need to be repeated regularly.

If it’s not possible to resolve the discharge, the owner will have to keep the skin clean and dry so it doesn’t become sore. The bonded companion of an affected guinea pig will often groom the area keeping it clean. Otherwise the owner will need to bathe it gently each day and carefully apply a barrier cream, such as Vaseline, to the skin (not the eye) so the tears do not burn the skin.