There are numerous and important issues to consider when hatching chicken eggs. Amongst the most important issues, selecting the correct chicken eggs, choosing an incubator and maintaining an appropriate incubating environment are deemed as critical.
Selecting The Correct Chicken Eggs
Inspection of the chickens who are responsible for laying and fertilising the eggs is paramount. Only eggs from healthy mature chickens who are not related to each other, were not disturbed during the mating period, have an excellent fertility percentage and who were are on a good quality diet should be considered. It is also important to visually inspect the eggs, which must of normal size and regular shape but not undersized or oversized when generally compared to those laid by your chickens.
The shell of an egg should be inspected for physical damage, for example, fractures or openings, as this may allow detrimental organisms, such as Salmonella, to enter the egg. Eggshells also contain a natural protective layer that helps prevent unfriendly organisms penetrating the egg and therefore care must be taken to avoid wiping or washing the egg, which could remove this unique coating.
To guarantee successful chicken egg hatching, eggs should be nurtured prior to incubation. Ideally, eggs can be stored, largest end up and at a temperature of 55 degrees Fahrenheit (13 degrees Celsius) with humidity of approximately 75 percent, up to seven days. Using a marking system, eggs must be turned daily. Before placing inside an egg incubator, cool eggs should be allowed to warm to the same degree of the ambient air temperature where the egg incubator is situated.
Choosing An Egg Incubator
There are two method of egg incubation. The first is the natural method of employing a setting hen or instead using artificial still air or forced air egg incubators. Although a setting hen is virtually maintenance free, setting can be stressful and the hen must be allowed to feed and stretch properly. For a significant quantity of eggs, forced air egg incubators are ideally suited for the job, as these particular units require minimal maintenance. However, still air egg incubators do need more attention for fewer eggs.
Egg Incubator Environment And Care
The temperature of both forced and still air egg incubators is vital. Still air egg incubator temperature should set at 102 degrees Fahrenheit (38.8 degrees Celsius) and forced air egg incubators set at 100 degrees Fahrenheit (37.7 degrees Celsius). The temperature of the egg incubator can be observed using a hatching thermometer by simply placing the probe of the thermometer at the same height level of the eggs and taking a reading. If required, the egg incubator heat source can be adjusted to accommodate any temperature differential.
To avoid moisture loss from eggs, during incubation days 1 to 18, the humidity present within the egg incubator should be a constant 58 to 60%. Humidity during days 18 to 21 should be increased to 65%. Throughout the incubation period, eggs should be turned 4 to 6 times in a day and must on the 18th day as further turning may cause injury to the chick inside the egg. It is advisable to have clean hands before turning eggs or handling hatched chicks. Unlike still air egg incubators, forced air egg incubators have egg turners installed to minimise maintenance. As chicks begin hatching, air vents within the egg incubator should be gradually opened to allow for correct ventilation. By day 21 of incubation, chicks should begin hatching and any remaining eggs by day 26 should be disposed of.
Candling hatching eggs is a safe and unique way of monitoring chicken eggs during incubation and is achieved by using a high-powered torch to check important issues such as fertility and viability of an egg including its moisture content. Candling provides a method of identifying problematic eggs that can help reduce the risk of a decayed egg exploding within an incubator and as of a consequence infecting the remaining hatch with harmful germs. Everyday, hens leave their nests for a brief period to feed, drink and exercise. Therefore, for the small period used times to candle incubating eggs, you can safely remove them from an incubator for up to 25 minutes and candle them without causing injury.
To make candling simpler, a torch with a focused beam of strong should be used. However, the light produced should emit very little heat as this may damage the embryos inside the egg. Consequently, torches that are purposely made for candling should only be used. Light emitting diodes (LED) have now become the main source of concentrated light in these specialist torches, which use very little battery power. When selecting a torch also bear in mind that some eggs have lighter and thinner shells making it easier to see inside and will require less concentrated light. If you intend to candle hatching eggs with darker and thicker shells as well as light shells then it would make sense to purchase a torch with a stronger concentrated light source.
Procedure For Egg Candling
Candling should start at day 4 of incubation and be carried out in a semi-dark environment. Remove all chicken eggs from the incubator and place them in egg cartons. Ensure lighting conditions are reduced and then in one hand hold one egg whilst placing the torch against the egg with your other hand. Visually inspect for non-fertile eggs, which will show as ‘clear’, and embryos that have begun to develop and stopped will often have a dark ring. These eggs must be discarded. Fertile eggs will show the embryo as a small spot with a web of blood vessels emanating from it. After studying each egg, return promising eggs back to the incubator. If you are little apprehensive in respect of certain eggs, lightly place a cross on them with a pencil and look at them again later. Over time, your experience and knowledge will increase, which will help you become more confident in selecting good eggs. It would also be beneficial to examine the contents of rejected eggs, as this will provide a valuable insight into what you had seen with the candling torch and what was physically happening inside the egg. You can continue to check and study the embryo development of your chicken eggs up to day 18 of incubation after which candling must stop to prevent injury to the forming chick.
Humidity And The Egg’s Air Sac
The air sac within an egg should enlarge during incubation as moisture evaporates. Consequently, if humidity levels within an incubator are correct the air sac will continue to increase each day. Conversely, if humidity is too high then the air sac will be smaller. However, if incubator conditions are too dry (very little humidity) then the air sac will be larger than expected.