Why do chickens lay eggs of different colorsIMAGE CREDIT woodleywonderworks

The genetics of the  hen determines the color of the egg. The pigments such as ooporphyrins and oocyanin responsible for the different color of the eggshell are deposited on to the eggshell as the egg passes through the oviduct of the hen. The pigment ooporphyrins is a derivative of haemoglobin, which is responsible for the brown color of the egg shell and oocyanin is a product of bile formation and responsible for the egg shell’s bluish green color. And in the absence of these pigments the color the eggshell remains white .

Therefore depending on the breed of the hen, different colored eggs are produced, Leghorn lays white colored eggs while Rhode island red lays brown colored eggs, and Araucana, an American breed, lays blue colored eggs.

The egg shell gets its color as the egg passes through the hen’s oviduct, a jouney which takes 26 hours. As the egg shell gets completed during the process depending upon the breed different colored pigments gets imbibed onto the egg shell.

Even though egg shell has different colors, the colors does not influence the interior contents of the egg such as its protien content.


[1] http://msue.anr.msu.edu/news/why_are_chicken_eggs_different_colors
[2] http://www.hindu.com/seta/2006/03/30/stories/2006033000471800.htm