Urine Marking in Rats

You should have noticed that rats like to move from one place to another when they urinate. Not only that, they urinate on almost anything from ground, walls and other objects, even other rats. It's not something they do for fun though, but it is actually a form of chemical communication between rats of the same species. Urine marking is rats' way of generating chemical odors they send as specific messages to other species; it's a form of territorial acclamation or sexual exhibition. When another rat receives the signal, it identifies, integrates, and then responds depending on the interpretation of the signal. The responses could either be behavioral or psychological.

Surprisingly, urine markings are actually a textbook of information about its maker. Information about sex, reproductive state, age, mating availability, idiosyncrasy, social identity, even the stress levels being undergone by the rat can be found in the urine markings and only other rats are able to interpret that. The urine mark could even show the indications of how long the urine has been since it was smeared on the surface.

Both sexes actually produce urine markings. However urine marking is more than half the time sexually dimorphic. One would notice that male species of rats mark more and heavier than the female species. Another disparity is that adult rats would mark more than juvenile rats and as well as intact rats than apparently neutered rats. Female rats would tend to follow their 4-5 days of reproductive period. They would mark a lot during the night before their ovulation.

In most occasions, rats would urine-mark surfaces or objects they have easy access to or something they can just immediately walk on. There are also times when they will mark their fellow rats, and they tend to mark on new odors they sense and over the urine markings of other rats.

The Urine-Marking process of rats is mostly attributed to their hormones. This is the very reason why most female rats would increasingly mark during the period before their ovulation and during it. This is phenomenon is strictly associated with the rise of estrogens and progesterone levels of a female rats during their heat periods. The male markings on the other hand are related with the rise of testosterone levels. That is why males would increasingly mark during their puberty and would steadily decline after it or even eliminated during instances of castration.

The markings can also elicit the circumstances that are taking place in the environment. The odor of the urine markings will enable the rats to know if a particular object has been moved from one location to another or show the presence of certain low objects within the area. Rats are able to distinguish those things with the use of their urine odors.

Moreover, urine marking serves many different purposes and functions. One of it is it serves as a sexual advertisement of a rat to its opposite sex. Males would begin to mark increasingly once they have perceived a female rat which happens to be in heat or receptive females. One the other hand, the receptive females would then detect which of the urine have high testosterone levels and they would choose them to have as their mate. Most intact males would regularly prefer the odor of the urine of receptive females rather than those that are not.

Urine marking may also serve as a habitat identification mechanism wherein the odor of their urine would make them feel that they belong to the place, making the environment's scent a much more familiar one.