There are high risks associated with any such flocks. Birds reared in cages are accustomed to the restricted environment, they know where to find water and feed, they know more or less all the group within a cage. Cage reared birds might be “lost” at transfer to the floor or 20 Laying Period Basic Growth Concepts ISA - Alternative management guide ISA - Alternative management guide aviary system, will not easily find their way to drinkers and feeders, are not accustomed to jump and mount on slats and into the system. Several days following transfer an increased incidence of weakened birds and mortality might occur, the flock also can tend to have a low peak with many eggs laid on floor.