What Sex is my Baby Skinny Pig?
Telling the sex of baby guinea pigs is even harder than figuring out on adults but with a little experience you can tell even on newborns. All of these photos were taken of babies at less than 24 hours old.
Females
Females have a very distinctive Y shape to their girl-parts. At the lowest point where the three lines intersect, the skin tucks inward. This indicates a female baby.
Males
Males have a Y shape to their boy-parts too. But in their case, their skin doesn't tuck inward. Without any prodding from you, the skin around the Y shape will look flush or possibly with a slight protrusion on the top part of the Y. There will be a tiny dot above the point where the three lines meet to form the Y (the urethra) but that is not always easy to see as it is so small on babies. Not shown in the picture is that if you put gentle pressure just above the Y shape, you should see the protrusion begin to poke out more (the penis). On a female baby, gentle pressure above the Y will not change the way her parts appear.
Sexing Baby Furry Guinea Pigs
Sexing furry guinea pigs is a little harder than on skinny pigs because, well all that hair gets in the way! But the body shapes are the same and you're looking for the same thing.
Females
You're still looking for the tuck inward on the upper part of the Y shape. Gentle pressure just above the girl parts will result in no significant change in appearance of parts.
Males
Pay close attention to the top part of the Y and look for skin that is flush or protruding (not tucking in) and the tiny dot that is the urethra. Baby boys can be very difficult to sex before they are a few days old and gentle pressure above the boy or girl parts will make a significant difference in visibility of gender.
