The poultry raiser who does not plan and lay the foundation for a better flock each year is missing an opportunity to increase his financial returns and to make each year's poultry crop more secure. Under present conditions the profit made by a flock of hens is usually in direct proportion to the fall and winter egg production of the flock. Production during this period depends very largely on the success of the poultry raiser in developing each year's flock of pullets into strong, vigorous, mature birds. In other words, the number of eggs produced, the size of the eggs (within certain limits), and the profit made from a flock of hens are determined to a great extent by the care of the chicks during the brooding period and of the growing pullets during the hot sultry days and nights of summer.
Alder, Byron, "Circular No. 72 - Brooding and Feeding Chicks" (1928). UAES Circulars. Paper 62.