Your rat has discharge that looks like blood coming from their eyes or nose (or both) and it scares the life out of you!! You think, NOW WHAT!!!!? Is my rat bleeding internally somewhere?
This is one of the biggest concerns new rat owners have. Often they will bring their rat in to the clinic because the owner sees red discharge that looks like blood around the rats nose and eyes. It is not blood, however, but instead, it is an organic compound known as porphyrin.
You may notice spatters of red on the bedding, or on the rats toys etc... Sometimes, when the rat grooms, the porphyrin gets on their paws and they spread it around to their fur. This will tinge light fur pink or even tan. Washing off with a warm wash rag and some baby soap usually works to rid the fur of porphyrin staining.
Porphyrin staining on paper towels, taken right from my own rats cage.
*Porphyrin staining on bedding, taken right from my own rats paper towels he had in his nest. He is not sick. He has had porphyrin discharge since he was a little baby. I started to notice it about a month after I brought him home, which meant he was around 8 weeks old. As of this date, which is Jan 12, 2010 (despite that the photo says it is the year 2010, batteries died so date is screwed up....LOL) he is now 20 months old and still has it daily, coming from both his eyes and nose. He is trained to use a 4 x 8 litter tray that contains yesterdays news. His cage is lined with newspaper under plastic needle point canvas and his diet consists of a balanced rat mix with treats being yogurt drops and also veggie crunches from the pet store. He rarely gets table scraps. Allergies are ruled out. We assume that the excess porphyrin drainage is non pathogenic and will only be something to consider should it increase in copious amounts.
Porphyrin stained paper towels from my rats cage.
So... where does porphyrin come from?
Good question, simple answer! Porphyrin is produced by a gland that is located behind the rats eyes known as the harderian gland. While have numerous functions, the true purpose of this lacrimal gland (tear gland) is not fully understood. Since the harderian gland is considered an exocrine gland, which functions are to produce secretions through a duct, such as the sweat glands, the salivary glands and other glands of the digestive system as well, the action of the harderian gland in rodents are to produce porphyrin that coats the rodents (and in this case the rat) nictitating membrane, also known as the third eyelid and keep them lubricated. So now you know what porphyrin is, the next thing you may ask is....
Why do I see it now and not other times? Rat owners are often startled when they notice traces of it around the rats nose and eyes. In some cases, small amounts around the nose can occur when the rat first wakes up, often when sleeping for long periods. A rat keeper that is in tune with their rats behavior will learn to tell what amounts are normal and what amounts are not normal. If you never ever see any discharge and all of a sudden after a year of owning your rat you find her nose and eyes are caked with the red discharge, this means that your rat is having some problems. Stress is usually one reason that the harderian gland produces an excessive amount of porphyrin. A rise in body temp, such as during a fever will also produce excess porphryin which indicates illness.
This is Bo, my rat that has had constant porphyrin discharge his entire life, which is 3.5 years as of this writing (11-08) Bo is high strung and so because of this, his body is a bit more anxious than other rats and he produces excessive amounts of porphyine discharge. The way to know when he may have a problem if I am to use porphyrin discharge as a diagnostic tool is to note if he also has it from his eyes, which he never does, and to also note other signs of illness such as lack of appetite and lethargy, weight loss and other signs of illness. Its really all about knowing your rat and what is normal for them.
Evaluate your rats over all condition. Is he eating and drinking? Is his energy levels normal? Does his coat appear soft and flat instead of puffy and dull? Has he been sneezing or congested lately? Is he walking straight or does he appear off balance and weak? If you answer NO to all of the above and the rat still has excessive porphyrin discharge, this still means a vet visit to be sure that things are ok on the inside since rats are famous for hiding pain and illness. I have had very sick rats have not a drop of porphyrin and I have had rats that live for 2 or 3 years with a red nose as if he just drank cranberry juice and did not wipe his mouth. Having porphyrin around both eyes and also the nose is also not normal in most cases. Also you may notice your rat has pink stained fur which means the rat has groomed himself and got the red mucus on his paws and in turn wiped it onto his fur. A white rat may turn pink in spots from the porphyrin. A wash cloth with a dab of soap will take care of it for the most part.
Porphryin is mother natures way of letting us know something is not up to par with our rats and this gives us a chance to call the vet and get the rat in for an exam. Although porphyrin does not always mean something is wrong, in many cases it does, and it should never be overlooked.