During the first 10 days of life, the chicks’ environment changes from that of the hatcher to that of the
broiler house, and there are significant changes in how and from where the chick receives its nutrients.
In the final stages of incubation, and as a very new hatchling, the chick receives all of its nutrients from
the egg yolk. Once on the farm, chicks must source their nutrients from feed in a sieved crumb or minipellet
form in the automated feeding system and on paper on the house floor. The early environment
(temperature, relative humidity, litter, access to feed and water) must make this transition as quick and
as easy as possible so that the chicks can establish healthy feeding and drinking behaviors. As a new
hatchling, the residual yolk provides the chick with a protective store of antibodies and nutrients until
a feed source becomes available. If the chick receives feed promptly after hatch, growth will be initiated
straight away and the residual yolk will mobilize as soon as feed enters the gut giving the chick a useful
boost to growth. If feed is not provided promptly after hatch the chick will be reliant on the residual yolk
for nutrients and growth will be delayed. Flocks in which some of the chicks have not started to eat for 1,
2, or 3 days will be uneven and the average flock weight at processing significantly reduced. Deficiencies
in early management or environment will depress both current and final flock performance.
As a target, if the entire flock has coped well with the transition from hatchery to broiler house, and
presuming that no environmental or nutritional factors are impeding growth, 7-day body weight should
be at least 4 times greater than day-old chick weight.