Even as a chick a hen has all the eggs she will ever lay in her ovaries, in an immature form called rudimentary egg cells (yolks- to- be ).
How quickly this supply is used up depends on breed, feeding, housing and hygiene.
If you use an artificial light to keep your hens laying through the winter their store of rudimentary cells will be used up faster. In her first year, a hen lays the largest amount of eggs that she will ever lay in one year, although the total weight of the eggs she lays stays roughly in her first and second year because in her second year, although the individual number decreases, the size of the eggs increases.
The size of the hen barely affects that of her egg. Take Wyandottes and Dutch
bantams for an example. In the picture the egg above is that of a Wyandotte
while the one below is from a Dutch bantam and Wyandottes are many times
the size of a Dutch bantam.
Colour also varies greatly from white to dark brown with beige, cream, blueish,
Greenish and pinkish at various ends of the spectrum!
In the formation of the egg the pigment is added last.
A yolk is released from the ovary and the albumen (egg white) forms around it, covered with a membrane.
The egg rotates through the body, giving it its form and then the shell is formed.
Last but not least the pigment is added.
There is a time in the year when hens will take a break from laying. Some people switch to cheeper food because the hens arent laying, but that is the wrong thing to do. By taking a break, the hens are recharging their batteries, so if anything, they should be fed better food!
You must have an adequate nestbox, or the hens will go and find their own place to lay, sometimes in a bush, or in a hedge or, more frustratingly, under the shed! Nestboxes should have a ‘lip’ at the front to stop the litter spilling out. They should be about 30cm wide and 40cm long. they should have 40cm walls to give the hen privacy, because, hens like quiet, peaceful, dark places to lay.
If you collect eggs daily, your hens shouldn’t get a chance to taste an egg but if they do they will probably start pecking open freshly laid eggs. A dark nestbox helps to prevent this behavior. Once they acquire this habit they are unlikely to stop unless you interfere, you can (most of the time) stop this behaviour by making a hole in an egg, spilling its contents on the nest box floor and adding non-toxic foul tasting liquid like mustard and chilli pepper.
Reduce stress, dont have bright lights around the nestbox. Chickens may also eat eggs because they are not getting enough calcium, so it is worth providing a calcium supplement, in liquid form to add to water, or as oyster shell grit. If this doesn’t work you can make a double bottomed nest box with sloping floor where the egg rolls down a crack to the bottom floor where soft material breaks its fall, so that it is out of the chickens reach.