Sexing Mongolian Gerbils

If you want to purchase a gerbil and certainly when you want to breed with your gerbils, it is important to know the difference between a male and a female. When you won't have any experience with sexing rodents, you might need some help. Don't believe the 'experts' blindly, because they can always be wrong. So check their gender always also by yourself. It isn't difficult. You cannot see the difference at a glance; you need to take a look under their tale. On this page you will find the information and pictures you need to sex your gerbils. Below this page you can see the pictures of male and a male Mongolian gerbil. You can also see the pictures of a male and a female fat-tailed gerbil (Pachyuromys duprasi) at the Fat-Tailed Gerbil page.

The main characteristics are:

The distance between the urinary and anal openings.

The scrotum of the male.

The scent gland.

The nipples of the female.

The size of their body.

The main characteristic you need to know to sex gerbils is, like most rodents, the distance between the urinary and anal openings. The distance between these openings in male gerbils is much larger than it is in females. This difference is more obvious when the animals are sexually mature.

Adult males have a large bulge at the base of the tail that is their scrotum. So their testicles are clearly visible. This bulge is obvious by 6 weeks of age and can be seen at least two weeks earlier. This is totally absent from females.

The scent gland (a small patch of bearskin just above their navel) is in males much larger, than in females. Dominant Mongolian gerbil, both males and females, have a larger scent gland than the gerbils that are lower in hierarchy. So if you have two females, the dominant female will have the largest scent gland, don't confuse this female with a male. In a group the dominant male will mark their territory the most. The dominant female second most followed by the younger males. The younger females hardly ever mark.

At an age of 2 weeks females have 8 bald spots on their belly, males don't. That's because at this age the nipples aren't covered with hairs. Very soon the hairs on their belly start to grow and the nipples cannot be seen anymore. Nursing females do often have obvious nipples.

Adult males are significantly larger than females, although this is not a precise method of sexing because gerbil size can depend on a number of other factors. The lower abdomen of the female is usually a bit rounder.