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Question:
Can a chicken egg come out round with no point?


Replies:
The shape of a chicken's egg can vary a lot, depending on the size, age and health of the chicken, My very small and VERY old (nearly 12 years) silky bantam lays eggs very occasionally - only about one a month. Her eggs are very small, about the size of a walnut, and they are almost round. They are slightly oval shaped, but the two ends are so close to the same shape it is very difficult, or even sometimes impossible to decide which is the 'pointy' end. Generally the shape of the egg is determined by the pressures exerted by the walls of the oviduct ( egg passage ) within the hen. A good healthy hen has strong muscles, which push the egg through fairly quickly, and mold the egg's shape as the shell is being formed. The 'point' is produced by the muscles pushing on the back half of the egg to move it through the passage. My old chicken has very weak muscles and her eggs move very slowly. This allows time for the egg to take the shape which is easiest for the egg - the same shape as a bubble - round. The shape of the egg has an added advantage for the hen. It stops the egg from rolling away from the nest. In the case of some seabirds who nest on cliff ledges, the shape is so stretched that the eggs are actually tapered like a cone.

Nigel Skelton


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