Chickens and Egg Production Assignment:
Year 10 Agriculture
Well researched information Adam. The section on Incubation was particulary good.
Grade = B+

Embryo development:

When the egg is laid there is some Embryonic development, however this usually stops until the right cell conditions allow it to continue. At first, all all of the cells are alike , but after the Embryo starts to develop, cell differences can be observed. From there the cells may become vital organs, a wing or a leg. Soon after, a pointed thickened layer of cells appear visible in the tail end of the Embryo. this pointed area is called the primitive streak, it is the longitudinal axis of the Embryo. This is where the head and backbone develops.
On the second day of incubation , the heart is being formed and joins to a vascular systems. this is when the heart starts beating.
By the end of the third day of incubation limb buds and legs can be seen. The mouth, tongue and nasal pits start to develop and the heart continues to enlarge even though it has not been enclosed within the body.
by the end of the fourth day most of the Embryo's parts can be identified.
After 21 days the chick finally begins to escape from the shell. After a few attempts the chick will finally hatch and the hatching is complete.
Egg Fertilisation:
When a rooster mates with a hen the semen is stored for later use. When the egg is ready to be laid it gets fertilized before the shell surrounds it. the sperm is only viable for a month in the oviduct.
The procedure for a hen to lay an egg takes 12 days .
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An incubator is a set-up that simulates the hen looking after the egg after being laid. The egg will spend 21 days in the incubator at 37-85 degrees and 65% humidity, being turned 3-4 times a day. This helps the embryo development as It helps the egg white to keep the embryo moist and cushioned during the rigors of incubation.
the conditions inside a incubator is very crucial for the development of the chicken. If the temperature is too high or too low the chicken may die. This also goes with the Humidity level needing neither to be too high or too low. The egg is not to be turned too much or too little either as that may consist of the chicken dying,
The procedure for a hen to lay It really doesn't matter the size or type of the incubator, as long as the right conditions can be supplied then the incubation will be
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Preparing Eggs for sale:
Before Egg can be sold to customers, the eggs will need to go through a specific procedure. These steps include:
Receivable: the eggs are picked up by refrigerated trucks and taken to be washed and cleaned to remove any dirt or manure.

Re-oiling: Here the eggs get their natural oil (bloom) removed, the eggs then get washed again going through a miro-fine mist of oil that re-coats the clean egg.external image Cleaning-Drying-Spray-Filming-Machine-for-Preserved-Egg-MT-300-.jpg
Quality Testing: Sample eggs are broken and the Albumen (egg white) is measured with a micrometre. The weight of the egg shell and colour and consistency of the yolk are also tested.
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Candling: This is where a strong light which allows the operator to see inside the egg to look for defects such as blood spots or cracked shells. These defected eggs are removed.
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Stamping: Each egg receives its unique code so it can be tracked to what farm it was collected from and on what day.
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Grading: Eggs are weighed and sorted mechanically between three and five grades that are available these grades are then marked on the carton.
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Packing: the eggs are now placed into carton with the use by date or best before labelled. The packed eggs are then kept in cool storage before distribution to retail outlets.
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Chicken breeds for laying:
The chickens used for laying eggs are the White Leghorn, Australorp and the Rhode Island Red.
White Leghorn: Small white bird that produces white eggs.
Australorp: Heavy black bird that lays creamy to brown eggs.
Rhode Island Red: Medium sized bird with reddish-black feathers with yellow. The Rhode Island Red lays brown eggs.

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White leghorn Australorp Rhode Island Red