To distinguish the sex of a kitten, it is usually judged based on the distance from the opening of the external genitalia to the anus. Lift the kitten’s tail. The opening just under the tail is the anus. Below the anus is the genital opening which is round in males and is a vertical slit in females. In kittens of similar size, the distance between the anus and the genital opening is greater in the male than the female.
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