Ostrich Eggs

25januari2006
Source: I. van Creij, 1991
Ostriches have the largest eggs in the world. Though in comparison to their weight the eggs are still small.
A hummingbird of 2 gram lays eggs of 0,5 gram. This is one forth of the entire body weight. Ostriches way 100 kg, yet their eggs weigh only 1,5 kg, which corresponds to 1,5% of its body weight. On average, an egg weighs about 7 tot 11% of the bird itself.

Ostrich eggs that are to be bred in an incubator can be disinfected with lukewarm water and diluted chlorhexidine. The egg skin should not be damaged, so itÂ’s best not to use a scrub sponge. The ideal environment to breed the eggs has a temperature of 95 F to 98 F and a relative humidity (RH) of 65% .

The RH affects the development of the air chamber. With a high RH, the loss of water will be little. In the last stage of the embryo phase this will lead to a higher death rate due to suffocation. Before breaking the shell, the chick will break the air chamber and use this air for pulmonary respiration.

The loss of water can be measured by weighing the egg daily. Under normal circumstances there will be a weight loss of 15% between the time of laying and hatching.