Causes of Blood in Rat's Urine

My pet rat is acting normal, eating and drinking normal but seems to have some blood in her urine. She always has dribbled little bits of urine when she walks around on us and has, ever since we got her. I assumed this was what they call "scent marking" but the other day I noticed the urine stream was a faded red color. I watched it very closely, gave her some cranberry juice and the next day her urine was a normal color. (Erin Anderwald - Colorado)

Small amounts of blood in a rat's urine and from the vaginal opening are one of the most commonly reported complaints from rat owners. Female rats do not menstruate, so any blood coming from this area indicates that something is wrong. The most common causes of blood in the urine or bleeding from this area are a uterine tumor, a urinary tract infection (UTI), or processes involved in pregnancy and labor. Assuming that your rat has not come in contact with a male rat, we can rule out the last cause. Both dribbling of urine and small amounts of blood in the urine can indicate both a urinary tract infection and a uterine tumor. However, given that one of these symptoms has been present for a while and your rat shows no other signs of illness, it is likely that your rat has a urinary tract infection. However, you need to have your rat thoroughly examined by your vet for the presence of a tumor. If he feels that a UTI is the probable cause, a course of antibiotics should clear this up.