Detailed Explanation of the Cloacal Sexing Method for Chicks

Among the various methods for sexing chicks, the cloacal sexing method is the most widely used in production because it is accurate and reliable. Its principle is as follows: in young chicks, a genital papilla can be seen at the opening of the cloaca of male chicks, about 2-4 mm long, with a tense surface, elastic, not easily deformed by finger pressure, glossy, and with distinct outlines; the cloacal opening of female chicks generally has no genital papilla, and even if a residual genital papilla is present, it is mostly atrophied, soft, non-elastic, lusterless, and easily deformed by finger pressure.

The best time for sexing is 12 hours after the down dries after hatching, when the difference in the morphology of the genital papilla between male and female chicks is most pronounced. Sexing too early makes the chick's body soft and makes it difficult to turn out the cloaca, and it also has a great impact on the chick; sexing too late causes changes in the genital papilla, making sexing difficult, and the anus is tight and not easy to turn open, so excessive force can easily injure the chick.

The operator uses the middle finger and ring finger of the left hand to hold the chick's neck, uses the left thumb to gently press the abdomen to expel feces, and places the right thumb and index finger on both sides of the cloaca, gently turning open the cloaca. If a spiral-shaped papilla is seen at the cloacal opening, it is a male chick; if it is a triangular flap-shaped fold, it is a female chick.