Experienced and professional animal trainer provide their insights in answering this question :
A. The green discharge may be indicative of infection. Any potential eye infection should be addressed by your vet or a veterinary ophthalmologist. An untreated eye infection may be painful and lead to permanent damage or vision loss. The other symptoms warrant a complete physical exam, diagnostics blood work and xray) and supportive care where indicated.

How to Identify Common Pet Problems ?

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Signs of conjunctivitis are often present in both eyes, and other signs such as coughing, sneezing, nasal discharge, lethargy, fever and decreased appetite may be noted. Mechanical irritation. Usually this chronic irritation is due to problems in the development of eyelid and eye lashes.
It is especially important that dogs go immediately to the veterinarian`s office when they show signs of an eye infection because the symptoms of an eye infection are similar to distemper symptoms. Your dog may also get other symptoms like vomiting, loss of appetite, and fever.
Usually a green or yellow discharge indicates there is a bacterial infection involved. Runny eyes can be a sign of an upper respiratory infection, more commonly known as `cat flu`. Cat flu is most commonly (over 90% of cases) caused by infection with feline calicivirus or feline herpesvirus.
Green or yellow eye discharge: This discharge is often due to a bacterial infection in the eye. Colored discharge is seen in infections, corneal ulcers, infected KCS or infected wounds on the eye`s surface. These conditions require antibiotics to treat.
Some of the signs of parvovirus include lethargy; loss of appetite; abdominal pain and bloating; fever or low body temperature (hypothermia); vomiting; and severe, often bloody, diarrhea. Persistent vomiting and diarrhea can cause rapid dehydration, and damage to the intestines and immune system can cause septic shock.
The clinical signs of more advanced kidney failure include loss of appetite, lethargy, vomiting, diarrhea, and very bad breath. Occasionally, ulcers will be found in the mouth.
What are the symptoms of canine distemper? Initially, infected dogs will develop watery to pus-like discharge from their eyes. They then develop fever, nasal discharge, coughing, lethargy, reduced appetite, and vomiting.
Other, less common symptoms include itchy skin, hives, and swelling of the eye and joints.
Some of the causes of increased tear production in cats include conjunctivitis (viral or bacterial), allergies, eye injuries, abnormal eyelashes (distichia or ectopic cilia), corneal ulcers, eye infections, anatomical abnormalities such as rolled in eyelids (entropion) or rolled out eyelids (ectropion), and glaucoma.
The biggest thing to remember is that eye discharge is often a sign of a more serious issue, and should be considered quite urgent when it comes to getting your cat the help they need.
If your dog has colored green eye discharge, yellow eye discharge or another colored eye discharge, schedule a vet appointment immediately. Other signs of a potential problem include squinting, a red-looking eye, or if your dog is rubbing or pawing at his eye.
The first sign of parvo for puppies is often lethargy, lack of appetite, and a fever. Canines will begin to suffer from vomiting and diarrhea as the virus progresses, and can experience dehydration and a high heart rate as a result.
Dehydration is very serious; dogs with canine parvovirus refuse water and quickly dehydrate due to their constant vomiting and diarrhea symptoms.
Some of the earliest signs of kidney disease in dogs may include subtle weight loss, urinating/peeing more often and drinking a lot more water. Therefore, if you notice your dog is peeing on the floor or asking to go out more, or if your dog is always thirsty, it`s time to visit your veterinarian.
‍Stage IV: Signs are at their worst because there are severe elevations of kidney values in bloodwork. Kidney failure can also cause painful ulcers in a dog`s mouth and make them feel sick, nauseous and weak, leading to poor quality of life in the later stages.
The near-death signs of parvo include severe lethargy, continuous bloody diarrhea, anorexia, and bloody vomiting. You may not want to admit it to yourself, but this is the point of no return. So consider doing a humane thing by putting your puppy to sleep.
In the U.S., people tend to get infected with parvovirus B19 more often in late winter, spring, and early summer. Mini-outbreaks of parvovirus B19 infection occur about every 3 to 4 years. Since parvovirus B19 only infects humans, a person cannot get the virus from a dog or cat.
Initial symptoms of canine distemper include an elevated body temperature (above 103.5°F or 39.7°C), reddened eyes and a watery discharge from the nose and eyes. More developed symptoms include lethargy, tiredness and eventually anorexia. At this stage, coughing, vomiting and diarrhea may also occur.
Canine adenoviruses (CAVs) and canine herpesvirus (CHV) are pathogens of dogs that have been known for several decades. The two distinct types of CAVs, type 1 (CAV-1) and type 2 (CAV-2), are responsible for infectious canine hepatitis (ICH) and infectious tracheobronchitis (ITB), respectively [1], [2].
In severe cases, dogs may experience lethargy, decreased appetite or weight loss. The most common clinical signs of Giardiasis include: Acute or sudden diarrhea. Soft or watery stool with mucus and a foul odor.
Giardia in dogs is a disease that causes a lot of watery diarrhea. Beyond diarrhea, Giardia symptoms in dogs can include vomiting, excess foul-smelling gas, decreased appetite, decreased energy, and frequent urges to poop.
Haws syndrome is an elevation of the third eyelid in both eyes. The third eyelid, or nictitating membrane, is a transparent eyelid some animals have that moistens and covers the eye for protection. In Latin, nictare is to blink.
It is especially common in shelters and breeding colonies, and often infects young cats. Most cats recover completely after a calicivirus infection, but rare strains can be especially deadly. The virus poses no threat to humans.
Epiphora in cats is a condition in which an excess of tears overflow from your cat`s eyes. This overflow does not cause discomfort to your cat, but will often produce discoloration around the eyes where the excess tears seep out.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. An immense amount of green eye discharge! A huge amount! And fever, exhaustion, lack.of appetite, stumbling
ANSWER : A. The green discharge may be indicative of infection. Any potential eye infection should be addressed by your vet or a veterinary ophthalmologist. An untreated eye infection may be painful and lead to permanent damage or vision loss. The other symptoms warrant a complete physical exam, diagnostics blood work and xray) and supportive care where indicated.

Q. My pet is suffering eyes discharge, what should I do?
ANSWER : A. Mucus, yellow-green pus, or a watery eye discharge can all be signs of conjunctivitis, which is inflammation of the lining of your dog’s eye.

There is a wide range of causes for conjunctivitis, from allergies, injury, birth defects, and tear duct problems, to foreign bodies, dry eye syndrome, infections or even tumors.

Other signs of conjunctivitis include excessive blinking or keeping the eye closed, squinting and pawing at the eyes.

Treatment of this condition depends on the underlying cause. In most of the cases cleaning, soothing the eye and applying antibiotics eye drops suffice but is some instances further investigation is required to establish the cause of the excessive eye discharge, and this should be performed by a veterinarian.

Q. Weak, discharge from eyes, swelling on right eye, does not want to open eyes. What is wrong?
ANSWER : A. If the discharge from the eye is green or yellow in color, it can indicate a secondary infection. Swollen eyes can be caused by a number of things ranging from allergies to infections, to injury to the eye itself or surrounding areas.

It is best to have your pet’s eye examined by your local vet. They will most likely wish to place a stain in the eye that can check for damage such as cuts or scratches. An ointment can then be given to help reduce inflammation, pain and take care of infection.

Until you can get to the vet, be sure to not let your pet scratch or paw at their eye as this can make things worse. You can also use a warm wet washcloth to gently remove any debris and allow the eye to open some, providing relief. However, if symptoms worsen, or the swelling travels to the face, head or neck, it may indicate a serious allergic reaction which should be treated immediately.

Q. My cat has entropion of the eyes. Vet did surgery on both eyes, the right eye seems ok but the left eye is still running/mucus. Can I use Neosporin?
ANSWER : A. Do NOT use Neosporin on cats or dogs as this product can be toxic to pets if ingested. If the eye is still leaking or has green or yellow discharge it is best to contact your veterinarian. Green or yellow discharge can indicate that a secondary infection has formed and may require antibiotics or cat-safe ointments to help clear it up. In the meantime, you can use a warm wet washcloth to remove any excess debris from the eye very gently, allowing the eye to open and help with healing.

Q. One eye is more red than the other. Last night he was pawing at it,today, he isn’t. Should I bring him to the vet?
ANSWER : A. Sounds possible that he had some irritation to the eye that is at least not itchy anymore. You can do either, having it checked now to confirm mild irritation, potentially due to debris or a topical irritant to the eye; or you can flush the eye with sterile saline eye wash (over the counter) using care not to poke or prod the eye and see if the irritation goes away on its own within the next 24 hrs. It has shown improvement already it appears, however if it is not cleared up and your pet seems irritated by it AT ALL, then it should be looked at by a vet and tested for a possible corneal scratch or ulcer. These can cause redness of the eye, eye discharge and pawing at the face. They are usually treated by prescription only topical eye antibiotic ointment and generally do very well after treatment.

Read Full Q/A … : Eye Problems in Cats

Q. My dog got into a fight with a cat. I think the cat scratch her eye. I clean it out with water. I have gentak can I put that in there?
ANSWER : A. It is best NOT to place anything in the eye unless specifically instructed to do so by your vet as it can cause more damage to the eye. As cat scratches and bites can easily become infected and the eye is a very sensitive area, it is best to schedule a veterinary appointment as soon as possible to have the eye examined. Your vet can place a fluorescent stain in the eye to check the extent of the damage and can then give you a pet-safe medication to place in it as needed to help it heal. Until you can get to the vet, it is best to keep the eye clean of debris and discharge with a warm wet washcloth, and to prevent your dog from scratching or clawing at the eye with the use of an Elizabethan (cone) collar.

Q. I was told by my vet that my dogs cherry eye was caused by something hitting his eye when he was poking around under a bush. I was told surgery needed
ANSWER : A. Prolapsed gland of the eyelid refers to a pink mass protruding from the animal’s eyelid; it is also called a “cherry eye.” Normally, the gland is anchored by an attachment made up of fibrous material. The most common sign of “cherry eye” is an oval mass protruding from the dogs’s third eyelid. It can occur in one or both eyes, and may be accompanied by swelling and irritation. He may have acquired it by getting an injury to his eye but this isn’t the case sometimes. Sometimes there is a weakness in the fibrous attachment.

The veterinarian will review the mass in the dog’s third eyelid and determine if there is an underlying cause for the condition. The diagnosis of the prolapsed gland could be scrolled or everted cartilage in the third eyelid, abnormal cells in the third eye, or a prolapse of fat in the dog’s eye.

Treatment often includes surgical replacement of the gland in the dog’s eye, or removal of the entire gland if the condition is severe. Conversely, if medications are recommended, they are typically topical anti-inflammatory drugs that are effective in reducing swelling.

Q. What can be given to dogs to stop the brown draining around dogs eyes? I was told tetracycline would work.
Thanks
ANSWER : A. Eye leakage is normal in some breeds of dogs, especially those that are more “bug-eyed” types. This eye leakage is just normal tears coming from the eye which can stain lighter colored coats. Unless there is an infection it does not need to be treated with antibiotics. Signs of infection usually include drainage that is thick or goopy and is yellow or greenish in color. Dogs with infections may also want to keep the eye closed, or may paw and scratch at it.

For plain tear-staining. Tear-stain wipes can be used around the eyes to remove the stain and bring the coat back to natural color. If infection is suspected, it is best to have your vet take a look at the eye prior to placing any medications in it.