Rabbits are prolific and early breeders and bunnies that are not separated soon enough may surprise you with an unexpected batch of new babies. Does -- female rabbits -- release eggs when they are bred, so it’s common for them to get pregnant after a single mating. To prevent such accidents it’s best to separate the sexes by the time they are 11 weeks old.
Determining the sex of very young rabbits is difficult, since they can be hard to hold easily and their genitals are so small that you may not be able to tell what you’re looking at. Depending on the size of your bunnies, you may be able to identify the sexes by the time they are about 6 weeks old. If you aren’t sure, wait until they are 8 or 9 weeks old and check again. Don’t be discouraged if you have to try a few times before you’re sure. Telling them apart gets easier as you gain experience and become familiar with what to look for.
Hold your rabbit in a secure position on its back so that it can relax enough not to hurt itself or you. A good way to hold each bunny is to place it on your lap with its head toward your body and its rear aimed at your knees. Handling your bunnies when they are very young can help to make this process easier since they won’t be frightened when you lift them up and turn them over.
Once you have the bunny in position, place one finger on either side of the anal area under its tail. Use gentle pressure to pull the tail down slightly and expose the genital area. The first thing you’ll notice is that what looked like a single opening is actually two holes. The anus is closest to the tail and the genitals are closer to the stomach. Apply a bit more pressure, pulling the skin down and away from the genital area and you’ll be able to determine the sex of your rabbit.
As you apply pressure around the genital area, you’ll see a small bit of tissue appear from inside the opening. In a female nothing comes out very far and the piece you’ve exposed will have a definite slit in it. If the bunny is a male, the tissue protrudes a lot more and is tubular, with a small round hole in the end of it. In an adult male rabbit the testicles are clearly visible on either side of the genital area, but when sexing babies the testicles are rarely present.