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Chicken recipes

Archaeological evidence appeared to support domestic chickens in Southeast Asia well before 6000 BC, China by 6000 BC and India by 2000 BC. Exactly when and where the chicken was domesticated was controversial. Inbreeding of White Leghorn chickens tends to cause inbreeding depression expressed as reduced egg number and delayed sexual maturity. When eggs are placed in a hypoxic environment, chicken embryos from these populations express much more hemoglobin than embryos from other chicken populations.

Reproduction and life-cycle

As with all birds, reproduction is controlled by a neuroendocrine system, the Gonadotropin-Releasing Hormone-I neurons in the hypothalamus. Sperm transfer occurs by cloacal contact between the male and female, in an action called the ‘cloacal kiss’. Chickens have been thought of primarily as providers of food, but their cognition, emotions, and sociality are comparable with other birds and mammals. Chickens are gregarious, living in flocks, and incubate eggs and raise young communally. The body is round, the legs are unfeathered in most breeds, and the wings are short. Chicken can mean a chick, and this was historically the meaning of the word chicken, as in William Shakespeare’s play Macbeth, where Macduff laments the death of “all my pretty chickens and their dam”.

  • For most of that period, chickens were a common part of the livestock complement of farms and ranches throughout Eurasia and Africa.
  • A cockfight is a contest held in a ring called a cockpit between two cocks.
  • Archaeological evidence appeared to support domestic chickens in Southeast Asia well before 6000 BC, China by 6000 BC and India by 2000 BC.

Africa

Domesticated chickens freely interbreed with populations of red junglefowl. Strongly inbred Langshan chickens display obvious inbreeding depression in reproduction, particularly for traits such as age when the first egg is laid and egg number. Only hens that could no longer produce enough eggs were killed and sold for meat. Only in the early 20th century, however, did chicken meat and eggs become mass-production commodities. Although many taxonomists and ornithologists consider it as a domesticated form of the wild red jungle fowl, some classify it as a subspecies of the red jungle fowl (i.e., G. gallus domesticus), whereas others, including the U.S.

Descendants of those domestications have spread throughout the world in several waves for at least the last 2,000 years. Chickens belonging to the same age cohort and sex are often kept together in industrial production settings. A flock usually includes one dominant adult male, a few khela88 subdominant males, and two or more females that are carefully watched over by the dominant male. Chicks are born covered in down, but they mature quickly, becoming fully feathered after four to five weeks. Fertilized embryos develop quickly, and chicks hatch approximately 21 days later. There is some debate about what the chicken’s scientific name should be.

By the mid-20th century, however, meat production had outstripped egg production as a specialized industry. For most of that period, chickens were a common part of the livestock complement of farms and ranches throughout Eurasia and Africa. Chicken domestication likely occurred more than once in Southeast Asia and possibly India over the most recent 7,400 years, and the first domestications may have been for religious reasons or for the raising of fighting birds.

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