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Chicken Physiology
- Life span: 10 to 11 years
- Heart rate: 220 to 360 beats per minute
- Respiratory rate: 12 to 37 breaths per minute
- Temperature: 103.6 to 109.9 degrees F
- Water intake: 210 to 400 milliliters per day
- Urine volume: 100 to 200 milliliters per kilogram of weight per day
- Gastrointestinal transit time: Approximately 4 hours
- Blood volume: 6 to 12 milliliters per 1/10 kilogram of weight
Chicken Reproduction
- Puberty: 4½ to 5 months
- Age at laying: Approximately 6 months
- Clutch size: 5 to 8
- Incubation: 21 days
- Birth weight: 30 to 80 grams
- Independence of chicks: 3 months of age
Chicken Anatomy
- Legs: Featherless in most breeds; can propel body up to 9 mph
- Nails: Sharp; used for scratching in dirt, grasping to perch
- Wings: Short flight feathers, limited lifting ability
- Tail: Short in hens, fuller in roosters; used for balance in flight and perching
- Ears: Sizable hole on either side of head, covered by feathers; fleshy earlobe just below ear hole
- Eyes: Set on the side of the head for a 360-degree view; sole means of identifying food; color vision superior to that of humans
- Beak: Jawbone covered with lightweight keratin sheath; used to pick up food, grooming and fighting
- Nostrils: Located on top of beak; poor sense of smell
- Mouth: No dentition; tongue used to push feed to back of mouth for swallowing
- Comb: Fleshy protuberance on the top of chicken’s head containing nerve endings and blood vessels; larger on roosters than on hens
- Wattle: Fleshy protuberance hanging below a chicken’s beak; contains nerve endings and blood vessels; and matches the comb color; larger on roosters than on hens