So you have your colony of rabbits. The does are all settled and happy, they have grown to a mature weight, and you are ready to start breeding. First, make sure that your does are actually at comfortable age and weight to become mothers. It's tempting to begin breeding as soon as possible, and rabbits can become parents at the ripe old age of 3 months, but it's important for your doe's well being to be patient and wait until she is ready, both physically and mentally. Very young does don't usually have the maternal instincts to properly raise a litter, and being pushed too early into production can have a negative impact on her ultimate growth.
Wait until she is 75 percent of her adult weight, or if you don't know what her adult weight might be, breed her at 6 months to kindle at 7 months. If she is a Giant breed, don't breed her until 8 to 10 months. Giant breeds take longer to mature.
Rabbits do not have regular heats. They come into "heat" upon stimulation from breeding, so it's recommended that you breed her, and then breed her again 12 to 24 hours later. Some breeders keep their buck in their colony, but that makes it impossible to prevent unwanted pregnancies. Does will breed back immediately after kindling, and raising two litters takes too much out of a doe. Keep them separate and control your population. Our bucks are kept in large conventional cages. I'll address how to care for your bucks in another post.
When you want to breed your doe, check her lady parts. A moist, swollen, purple-red vent indicates that she is ready to breed and will probably be receptive to the buck. If her vent is puckered, dry and light pink, she will not let him breed her. If her vent looks right, pop her into the buck's cage. There will be a few indicators when he "gets" her – he will probably flop over to the side, make noises, and he may cry or flop his ears (if he's not already a lop breed). If he's simply riding her around the cage, he hasn't bred her.
If they have successfully bred, you'll have little ones in 28 to 32 days. If she hasn't given birth by day 35, assume that she is not pregnant. You may palpate her (check for pregnancy by feeling her stomach area), or have someone palpate for you. There is a chance of retained kits, which will require medical attention, but for the most part if she hasn't kindled then she probably was not pregnant. Palpation can help you figure out if she is pregnant by the second week of pregnancy, but it is not always reliable. Always provide a nest space if you bred your rabbit unless you are very good at palpation and can determine that she is not pregnant.
As it gets close to day 27, it's time to provide a box. Provide them early so that the doe has time to build a nest, and just in case she gives birth early. A large plastic tub makes an excellent nest box, because it is warm, spacious, and protects her and the kits from the elements and other rabbits. Drill holes in the bottom and sides for ventilation and drainage, and cut a large hole in the front to get in and out. Make sure to leave an edge on the bottom of the box under the entry hole so that babies don't crawl in and out. With this design, the doe can fill the box with bedding to make a natural, safe space for her babies.
You wouldn't even know that there are babies in here, would you?
Sometimes multiple does will choose to nest in the same box, which is completely fine. Just check each day to make sure that all the babies are getting fed. If there are some that look wrinkled and underfed, move them to a box with a smaller group of babies. Here are two does that share a nest, checking out the box after it's just been cleaned. These boxes do need cleaned quite frequently because they quickly get wet.
Babies can be weaned after 8 weeks of age. Any younger than that and you compromise their growth rate, overall health, and in some states it is illegal to sell kits under 8 weeks old. Twelve weeks can be even better for market rabbits, but remember that rabbits may begin breeding at 12 weeks, so if they are going to be living past fryer age (10 to 12 weeks) they should be separated by gender.