The heart beat of chickens is rather fast, being about 286 times a minute in males and 312 in females in a resting condition. Digestion rate is somewhat rapid in chickens. The chicken's temperature is about 107 degrees to 107.5 degrees F. Chickens are hatched, not born in the truest sense of the word. Chickens are covered with feathers but have a few vestigial hairs scattered over the body. The average consumer does not see these hairs, because they are singed off in the processing plant.
Any mastication occurs in the gizzard.
Many commercial poultry producers do not provide grit to their chickens, because they feed a ground feed of fine meal consistency that can be digested by the bird's digestive juices. The chicken has pneumatic bones, making its body lighter for flying, if it had not lost the ability to do so. There are 13 air sacs in the chicken's body, again to make the body lighter, and they are a functioning part of the respiratory system. Chickens have comparatively short life spans. Some live to be 10 to 15 years old, but they are the exception, not the rule.