Eggs and bird health

The humble chook egg, facts broken down, and more about your feathered friends and the general health of your flock

Besides a ton of protein, eggs contain far more than just a white and a yolk... read more below

Chooks can be found virtually all over the world and its believed that wild fowl were domesticated for both their eggs and meat more than 5000 years ago.

First some facts about the egg.

The egg shell, eggs should be kept clean, uncracked and dry. Bacteria can penetrate into the egg even through a unbroken shell 

Shell Colour, shells vary in colour and vary from breed to breed, however generally there's no relation to the colour of the shell to the quality of the egg or flavour.  However, I do believe there is a subtle difference in sweetness in some of the breeds such as Leghorns to Aracuana for example 

Freshness, eggs need to be harvested daily, store them in a FRESH appropriate cardboard container and placed in the fridge. Freshness is lost in a ratio of three weeks in a fridge equal to three days at room temperature. So next time you stare at the eggs in your local supermarket on an unrefrigerated shelf, you can estimate the age of the eggs  as a week for each day on the shelf!

Yolk Colour

Ever wondered why there's so much difference in the colour of a yolk? Some are pale yellow and some almost orange. The fact is, it doesn't make much difference, however the deeper colour always makes the egg look so much fresher. What makes the difference in colour?  Well caratenoid pigments in the plants they consume accumulate to pigment the yolk. If the chooks free-range, they collect these caratenoid pigments through the consumption of the matter they eat.  So if you can't free-range, it's somewhat wise to feed them plenty of vegetable matter and food scraps.  Not only is it healthy, it keeps the ladies occupied and provides that well needed caratenoid pigment.

The composition of the egg

The egg is widely known as one of nature's compete foods containing all of the essential amino acids, vitamins and minerals, no wonder it's an all-day food item in the fridge.  And more reasons why you should nurture your own flock.  The egg consists of the shell mainly made of Calcium Carbonate and is quite porous allowing gasses and water to evaporate, and if kept in the fridge and not in a suitable container it can absorb other flavours inside the fridge such as onions.

Next, inside the shell is the membrane.  This acts as some sort of barrier preventing unwanted bacteria spoiling the egg.  We now see the two things we all know and understand, the egg white (Layered Albumen) and the yolk.  You will also see what looks like a stringy piece, this is the Chalazae which acts as an anchor to hold the yolk to the centre of the white.   If you see a very small white spot in the centre of the yolk's surface is the Germinal Disc.  This indicates that the egg has been fertilised.  This is interesting, since should you purchase fertile eggs from someone, you can check if they are fertile by breaking one open and looking for the Germinal Disc.

Blood spots in the egg.

Blood spots on the yolk.  They present no harm the to consumer so please stay assured. Blood spots occur when a yolk is released from its follicle in the ovary. The follicle mostly bursts a line (the Stigma) that may contain blood vessels.  If that follicle does not tear exactly long the Stigma a tiny blood vessel may be torn resulting in the formation of a blood spot in the Yolk.  No need to worry, just remove it if it bothers you.

And the last piece of information about the egg.

Yolks and Runny whites, When you crack a fresh egg into a pan the yolk should stand almost as equal to half the size of the egg.  When the egg is ten days old, the height of the yolk will diminish by about one third, and by the 17th day the yolk is almost as flat as the white. So next time you buy eggs you can check the freshness in this manner.

Now for runny whites (Albumen) can be caused by a number of things such as age of the hen, age of the egg, health of the hen and nutritional intake. As the hen gets older the whites get runnier and the intake of protein is compromised.  Its most important to provide adequate water supplies and efficient shelter to avoid reduction to food intake. 

And now let's see what to buy, new stock as in chickens or older pullets at 16 weeks  old up and to POL (Point of Lay).  Or simply replacing your flock by incubating and rearing young chickens and pullets.  Click here to find out more