Equations involving heat and mass balances were used to
estimate the components elements of the incubator. The
physical and biological elements of the egg incubator were
conducted. The physical measurements involved the use of
thermometers to measure the ambient and incubator
temperature while temperature-relative humidity sensor was
used to monitor the ambient and incubator chamber
conditions. A sliding device as a provision for regulating the
degree of ventilation rate through openings ensured that
proper ventilation was maintained within the incubation
chamber.
While egg positioning and turning were done manually at
45o rotation, using a lever handle at six hourly intervals. This
prevents the sticking of egg yolks on the shell.
Eggs set on their sides must be rotated 1/2 turn at least 3
times daily. Eggs set with the air cell end up should be tilted in
the opposite direction 3 times daily. This keeps the embryo
centered in the egg and prevents it from sticking to the shell
membrane.
If hand turning, to insure proper turning, mark each side of
the egg with a pencil. Put an "x" on one side and an "o" on the
opposite side. Stop turning the eggs for the last three (3) days
of the incubation cycle (at 18 days for chickens, 25 days for
waterfowl, etc.) and do not open the incubator until the hatch
is completed to insure that a desirable hatching humidity is
maintained.
Four factors are of major importance in incubating eggs
artificially: temperature, humidity, ventilation and turning. Of
these factors, temperature is the most critical. However,
humidity tends to be overlooked and causes many hatching
problems. Extensive research has shown that the optimum
incubator temperature is 100°F when relative humidity is 60
percent. Concentrations of oxygen should be above 20
percent, carbon dioxide should be below 0.5 percent, and air
movement past the egg should be 12 cubic feet per minute.