"The sexing of Rabbits, even at a very young age, is comparatively simple, but like very many aspects of rabbit keeping, it is best learned by a little practical guidance from a knowledgeable person. Apart from the sex organs there is generally little difference between the appearance of the sexes although the buck often has a broader head and is usually the smaller of the two. The easiest way of sexing a rabbit is to hold the rabbit with the palm of one round the back of the rabbits head, with the thumb in front of the ears, and with the rabbit lying on its back on the operators lap. With the other hand, the thumb and index finger (or the index and middle fingers) are used to gently press on either side of the sex organ. At around six weeks of age, the organ of the buck will appear rounded whilst that of the doe will be slit-like or V-shaped. With increasing age these differences will become more and more apparent. With a mature buck the scrotal sac will usually be apparent, but it should be noted that the buck can withdraw the testicles into the body cavity, and the apparent absence is not therefore a completely certain guide. The sexing of newly born rabbits requires both experience and practice and except in special cases is unlikely to be required by the newcomer." http://islandgems.net/sexing.html

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