Real and fictitious hatchery incubation in an incubator
How to count the hatchability of chicks in an incubator. Real and fictitious deducibility.
After the withdrawal of the chicks in the incubator, beginning poultry farmers often have a question:
How to calculate the hatchability of chicks correctly?
The answer, at first glance, is very simple: We took 100 eggs, brought out 60 chickens – that means hatchability of 60%
And this answer is wrong. The fact is that in this formula does not take into account the so-called. “Infertility.” (The incubator should not “be responsible” for unfertilized eggs, this responsibility is borne by the cock, and it has its own indicators :-))
As a rule, in each egg laying for incubation, unfertilized eggs are present (in general and about 20% average) and it is possible to reveal them only at the first “ophoscopy”, which occurs a week later, after laying eggs for incubation.
After the first ovoscoping, the eggs remain in the incubator, which the poultry breeder considered normal and viable to the conclusion.
It is from this figure that the formula for calculating deducibility should be based. This is a real indicator based on the confidence of the poultryman that ALL of the chickens will be hatched from the selected eggs. But the further process (the next 2 weeks of incubation) will show how the specific incubator copes with the incubation of eggs.
And the value of hatchability will be real. In other words, the responsibility for the first third of the incubation period is borne by the poultry farmer, and the next 2/3 is taken by the incubator).
* It should be noted that in the meaning of “real hatchability”, counted by this method, there is a small error formed by individuals with genetic abnormalities. Given the meager percentage of such material, we believe that this indicator can be neglected.
So, we have determined the actual method of calculating deductibility, in which it is possible to compare the indicators of incubators of different manufacturers.
And what about the figures that many incubator manufacturers write, for example, “the hatchability of our incubator is 97%”!
Or those high figures that many users give on the poultry forums and thematic video channels Youtube?
It turns out that the value of hatchability can be easily manipulated, adjusting the figures to a high percentage.
If, for example, for the reference point, take the number of eggs in the tab after the 2nd ovoscoping.
Let us explain such manipulations using simple examples:
The initial data-100 eggs were bought, 60 chickens were taken out, 10 eggs were removed after the 1st ovoscoping, 10 eggs were removed after the 2nd ovoscoping)
1. Real hatchability: 100 – 10 = 90 (60/90 * 100 = 67%)
2.Flexive deducibility: 100 -10-10 = 80 (60/80 * 100 = 75%)
In the first case, the incubator “takes responsibility” for 21-7 = 14 days of incubation
In the second case, the incubator “takes responsibility” for 21-14 = 7 days of incubation (and in case of ovoscoping on day 18 – for 3 days of incubation)
In the examples given, it is clearly visible that the value of hatchability of the incubator can be easily manipulated, adjusting the results “to the desired values.”
In conclusion of the article, we give the formula for calculating the real hatchability of eggs in an incubator:
H = С / (L-U) * 100
H-hatchability of the incubator, (in%)
L-laying eggs in an incubator, (in pieces)
U-unfertilized eggs, (in piece), after the 1st ovoscoping (usually after the 1st week of incubation)
C-chickens, (in pieces)
All successful brood chickens with a high percentage of hatchability!