Chick sexing is the method of distinguishing the sex of chicken hatchlings, usually by a trained person called a chick sexer or chicken sexer.[1] Chicken sexing is practised mostly by large commercial hatcheries, who have two different feeding programmes, one for the females (or hens) who are destined to lay eggs for commercial sale, and the others for the males (or roosters), most of whom will be disposed within days of their hatching because they are irrelevant to egg production. A limited number may be kept and fattened for their meat. The chicken sexer puts the chicken hatchlings on the appropriate track early, enabling those chickens to receive optimal nourishment for their likely commercial role from an early age. Different segments of the poultry industry sex chickens for various reasons. In factory farms that produce eggs, males are unwanted; for meat production, separate male and female lines for breeding are maintained to produce the hybrid birds that are sold for the table, and chicks of the wrong sex in either line are unwanted. Chicks of an unwanted sex are killed almost immediately to reduce costs to the breeder.
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Methods of chick sexing
There are two chief methods of sexing chicks: feather sexing and vent sexing.
Feather sexing
Feather sexing is easy, but it requires that the chickens be specially bred to manifest their sex in differences in the feathers as hatchlings. Male chickens in these breeds have longer wing pinfeathers than the females do, which makes them relatively easy to tell apart. Most chickens do not have these traits bred into them, and the hatchlings are identical to all but the skilled eye of the professional chicken sexer.
Vent sexing
Vent sexing involves literally squeezing the feces out of the chick, which opens up the rectum (more properly, the cloaca) slightly, allowing the chicken sexer to see if the chick has a small "bump", which would indicate that the chick is a male. Some females have very small bumps, but rarely do they have the large bumps male chicks possess. Vent sexing is not easy. The sexual organs of birds are located within the body; the professional vent sexer has studied their external appearance, which can fall into as many as fifteen basic patterns, and learned to identify which ones are male and which female. Vent sexing is a difficult trade to master; many professional vent sexers are Japanese, where the art originated. The mystery of vent sexing was revealed to the Western world when a seminal paper was published in Japan in 1933 by Professors Masui and Hashimoto, which was soon translated into English under the title Sexing baby chicks. After Masui and Hashimoto's discovery, interested poultry breeders brought in people who had been trained by them to teach the art, or sent representatives to Japan to learn it. The skill is complex and has been likened to skill at playing chess and other crafts or games where pattern recognition is the key to success.
Alternative methods
Small poultry farmers whose operations are not of sufficient size to warrant hiring a chicken sexer must wait until the hatchlings are four to six weeks old before learning the sexes of their chickens. At that time their secondary sex characteristics begin to appear, making it possible for anyone with a minimal amount of training to sex a chicken.
Trivia
- Chick sexing was featured in episode 7 of Dirty Jobs.
- Chick sexing was a former occupation of a main character in the Australian film Mr. Accident.
See also
External links
- Poultry: Sexing of day-old chicks
- Gender identification of chickens prior to hatch (PDF)
- How to tell the sex of Chicks - including general signs, breed specific tips and old wives tales.
- Abstract: The art of chicken sexing - a cognitive science discussion
- The art of chicken sexing - full article (PDF)
