This could be a sign of a few different things.I would first change the type of cat food you are using and see if that helps.It could be something she is eating to make it discolored.If that does not work,I would then take it to a vet.Cats have different parasites they can easily get and may need to be treated to ensure your cats health.
The Herpes you gave it.
The walls of the small intestines soaks up all of the liquid in it and it carries it to the rectum and after it travels through the rectum it exits through the anus. That is how a waste molecule takes waste out of the body.
A cecum is a primitive rectum, where both solid and liquid waste collect before being expelled from the animal's body.
This residue that you are speaking of is most likely the mucus that keeps your rectum lubricated when you have a bowel movement. Having a little mucus drip onto your underwear is normal, but contact your doctor if the mucus turns bloody.
it happens when infection lodged in anal glands, that is present around anal opening.
the rectum
the rectum is attractive
The large intestine does connect to the rectum.
A fart is the air that comes out of your rectum and often makes a sound. Pee, or urine, is the yellow or clear liquid that comes out of your body after you drink something.
Nothing is digested in the rectum, the rectum is the final storage place for feces before they are excreted.
The rectum.the rectum or the decending colon.
Cancer of the rectum is the disease characterized by the development of malignant cells in the lining or epithelium of the rectum