If you are one of the vast majority of people who have seen or had dogs or other land mammals as pets (of course we are talking about the kind of animals that fit in an apartment without having to leave it), it may seem ridiculous to imagine that someone not know how to identify their sex. Oddly enough, there are people who have never seen a dog up close, for whatever reason. Read us to the end and you will know how to identify the sex of our most common four-legged friends. If you are not, still stay with us. You could learn a little more. Some extra knowledge won’t do you any harm.
Sex of a dog in an adult state.
It is extremely easy to know the sex of an adult dog, just look at the genital area. Of course, in the puppy stage it is not so simple, especially in the first weeks of life. And furthermore, we may someday find an animal with genetic mutations or deformations, such as a case of hermaphrodites (which is the perceptible or invisible existence of both sexes in an organism). These cases are the exception and not the rule. We will deal with the rule and we will leave the exception to the scientists that are what they are for, right?
A bit of evolutionary history
Dogs, like humans, are mammals, and the reproductive system of mammals is usually quite similar, except for the obvious differences between species. In mammals, the sexes are normally separate and reproduction is placental viviparous except in the group of monograms (which lay eggs).
These are the most primitive, retaining some features of the reptiles, from which they descend. Marsupials (kangaroos, koalas and several others) are also not placental viviparous, since the young have a very short development in the womb and much of their growth is completed in the bag or marsupial. Except for these two groups of mammals, the rest are placental viviparous, which means that the young develop completely in the mother’s placenta until they are born. This is the case of dogs and how they are born.
This specialization in reproduction inevitably leads to an equivalent specialization and differentiation in the sexual organs, both internally and externally. In the males of most mammals it is possible to see externally (the part that interests us) the penis and the scrotum that contain the testicles inside, while in females the vulva is identifiable as an external part of a complex genital apparatus. . As we can see, they are systems very similar to those of humans, and as we said before, their characteristics are common and shared by the vast majority of mammals.
So what are the differences?
We already told you: it couldn’t be easier. Looking at their genital area is usually enough. Males have a penis and scrotum (if they are not castrated) and females have a vulva. They can even be identified by the way they urinate, which is not the same. Adult males raise their legs to do so (we have seen more than one dog marking territory in this way) while adult females bend down to urinate.
But sometimes this method is not 100% safe, as some very dominant females will also raise their legs and mark their territory (it is rare but not too rare), and some very old or debilitated males will bend down to urinate, simply because they do not they have the strength to lift the leg.
In puppies things vary a bit. Although they are not so difficult to identify, we will not be able to use this last method, because in the first months of life both sexes urinate in the same way (crouching). The breed of the puppies can also have a great influence, especially the differences in size and the amount of hair: the larger the breed and the less hair it has, the easier it will be.
Males are born with a barely visible scrotum, since the testicles are not completely descended and are protected in the abdominal area, from where later, around eight weeks after birth, they will descend and the scrotum will become more voluminous and visible. In the central area, just below the navel (or the umbilical cord if they are newborns) we will identify the penis, which will be in the form of a small protuberance with a very faint hair on the tip.
Further down, between the hind legs and almost in the anal area, we will find the scrotum, which, as we have already said, will not be marked or very visible. Never confuse, for example, the navel or umbilical cord with the penis. The penis will always be below it, so you should see two bumps. This pup is definitely a male.
The females do not have more protuberances in the central area than the umbilical cord or the navel (the latter will be less visible as they grow). In the area between the hind legs they will present the vulva, small, sometimes in the form of a fold but never similar to the male scrotum. The vulva is the only exposed area they present, since almost the entire reproductive and sexual system of females is inside. If it has a vulva, it will be a female.
Other details to know if a dog is female or male.
It is not recommended to handle newborn puppies, except in strictly necessary situations, as they are extremely fragile. In addition, the mother can bring out her protective instinct and we may get a good scare even if she knows us well or has played with us, or even if we own her. Instinct is instinct.
If for some reason you need to know the sex of your puppies and you don’t have much experience, find someone who does and who can help you find out, touching them as little as possible.
