The procedure for ovoscopy of chicken eggs is used when hatching chickens. The technology of candling eggs to find out whether there is an embryo inside appeared a long time ago. At first, ordinary candles were used for this purpose. Currently, there is a special device - an ovoscope.
Features of the procedure
Ovoscoping is a simple, but very informative way to determine the embryo inside. For the procedure, a device is used - an ovoscope, which shines through the shell, and it becomes clear what is inside.
Ovoscoping can be done at any time. An ovoscope is a small device with a light source inside. The upper part is a plate with a small hole for laying eggs. You can also purchase a portable ovoscope, which looks like a flashlight.
What is it for?
You can raise chickens without an ovoscope. But thanks to ovoscoping, it is possible to control the process at all stages of incubation and immediately throw out eggs that do not contain an embryo.
A normal egg, without various defects, looks like this:
- The shell is completely homogeneous, without damage.
- At the rounded end there is a small air chamber, separated from the shell by a transparent film.
- The yolk is located in the center (there should be one, sometimes there are two yolks inside).
- If you start to rotate it, the yolk slowly turns.
- There are no black spots or blood spots inside.
Only healthy eggs are suitable for hatching chicks.
How does the process work?
Ovoscopy is very simple. Before the eggs are placed in the incubator, they are examined using an ovoscope. They are placed on the device and turned on. They shine through the shell and it becomes clear what’s inside.
Selecting Tools
Nowadays there are a large number of ovoscopes, and it is often difficult to choose a quality device. First of all, when choosing an ovoscope, you should pay attention to the voltage of the device. Devices with a voltage of 220 volts are suitable for purchase. Such an ovoscope will clearly illuminate the shell, and all defects will be noticeable immediately.It is not recommended to use an ovoscope with less voltage. During ovoscopy, not all defects may be noticeable.
Another factor is power. It is worth buying devices for which it is equal to 25 W. Using this device you can enlighten up to 15 eggs.
In this case, the whole procedure will take no more than 15-20 minutes.
The only disadvantage of the ovoscope is its price. A high-quality apparatus will be expensive, so if chickens are bred for a small farm, buying an ovoscope is too expensive. Moreover, you can make it yourself from available materials. Or use a regular flashlight.
Ovoscopy of chicken eggs by day
It is not recommended to get carried away with frequent ovoscopy. Especially if the chickens are hatched by a hen. If the bird is constantly disturbed, it will be very stressful for it, and it may completely leave the nest. In addition, there is a risk of damaging the shell and the unhatched chick.
If the eggs have just been laid, there is no point in candling them right away. But you can perform ovoscopy on the first day. It often happens that there are two yolks inside; such an egg is unlikely to hatch into a chick, so it can be removed immediately.
For the first time
For the first time after laying the eggs, nothing will be visible on the ovoscope. During this period, the organs of the embryo are just being laid. The egg is dark yellow when examined. There should be no dark spots inside.
3rd day
Having carried out the procedure during this period, you can see that the space inside has become lighter. If you apply a stethoscope to the surface of the egg, you can hear the embryo's heart beating.
4th day
A blood network appears inside the egg, which is clearly visible, and a dark clot in the middle. At this time, the beak, reproductive organs and wings are formed.
5th day
You can already see the umbilical cord, which comes from a dark blood clot in the center of the egg, and you can also see the anatomical sac - the membrane that protects the embryo. If you look closely, you can see a small dark dot in the center of the clot - this is the eye of a chicken. Blood vessels become thicker and darker.
6th day
The vascular network becomes larger and darker. The clot is blurred, its edges are no longer so clearly defined. The black dot (eye) becomes even better visible.
7th day
On the 7-8th day, the space inside becomes darker and takes on an orange-bloody hue. Blood vessels are clearly visible. The chicken continues to develop internal organs.
If you open the shell during this period, you can see that the chick’s first feathers are beginning to form.
11th day
At this stage, the condition of the allantois is usually assessed. If the chick develops normally, the allantois fills everything inside the shell and closes at a pointed end. If you look closely, you can see the outline of a chick. Gradually the chicken increases in size, the space becomes darker.
15th day
The egg appears almost black, the chick fills the entire space. Almost all of his organs were formed. At the same time, it is noticeable that it is on one side, and the opposite part of the chick seems very light.
Day 19
At the end of the incubation period, no changes are visible. The chick has filled the entire space, and when examined, the egg appears black. The gap should no longer be noticeable during this period. If you look longer, you will notice how the chick moves. Usually on the 19th-20th day the chicken already pecks a hole in the shell.
What defects may appear during the incubation process?
Candling the shells before placing them in the incubator and during the entire incubation period will allow you to immediately discard eggs that are unsuitable for hatching.
What defects can be noticed:
- Poorly defined vascular network.
- The appearance of a blood ring.
- Presence of blood spots.
- Light lines.
- Foreign bodies inside.
- The appearance of dark spots - mold.
- The air space is moved from the edge of the shell towards the center, towards the side or pointed end.
- The yolk flows from side to side.
- The yolk froze in one place during turns.
- Streaks of blood.
When viewed through the lens, a red circle may be visible inside. This indicates that the embryo died. The red dots appear due to the same thing. If during the procedure the chick occupies all the space and moves, it means that it will hatch soon.
At first, it can be difficult to identify defects inside. Experienced poultry farmers who have been doing this for many years can immediately determine which egg will hatch into a chick and which will not.
DIY ovoscope
You can make an ovoscope yourself from available materials. To do this you will need a light bulb and a cardboard box. A light bulb is attached to the bottom of the box. The top of the box is covered with a lid with holes into which the eggs will then be inserted. By pointing a light bulb at the egg, you can illuminate it and see what's inside. If you don’t want to do an ovoscope, you can shine through it with a flashlight.
Another way to make an ovoscope is to use a tin can. You need to take a light bulb and insert it into the socket. Cut a hole in the jar so that the egg does not fall through. Place the testicle in the hole, turn on the light bulb and examine it.
