Avian Production Management

TURNING OF EGGS

• Once the egg is placed under incubation the specific gravity in egg lessens and the yolk settled in the thin albumen raises to come in contact with the outer thick albumen if the egg is not turned. Therefore frequent turning of egg is essential for movement of embryos in the eggs during first phase of incubation to avoid sticking and setting of embryos to shell and deaths. Similarly, turning facilitates uniform heating of egg contents in auto operated incubators.
• Usually tilting of egg through 45^oangle on both the sides on their perpendicular axis for 4-5 times a day leads to maximum hatchability. Turning is not required in hatchers or it is stopped from one day before the actual commencement of hatching.
• The turning must be gentle as vigorous turning may lead to blood ring formation with increased mortality.