Eggs changing colour
QMy hens all started to lay dark brown eggs at the beginning of the season. I’ve noticed that the eggshell colours have got lighter over the season. Is this usual?
AJulie Moore said: Eggshells and colourings do vary within breeds but what you are experiencing is perfectly normal. Hens do lay darker eggs at the beginning of the season after the winter break. The amount of pigment will lessen throughout a hen’s laying cycle so she’ll lay progressively lighter eggs.
All eggshells start out as white. Coloured eggs have their pigment added to the shell at the end of the shell formation process in the shell gland.
Brown eggs are the result of the pigment protoporphyrin, a by-product of haemoglobin in the hen’s blood, being deposited on the eggshell during the last part of the formation of the egg. The brown colouring is not part of the shell, but more like paint on the surface which can easily be rubbed off.
Different breeds have differing amounts of pigments which is why Buff Orpingtons lay pale brown eggs whilst Marans lay dark, chocolate brown eggs.