Suleiman Sheikhi1, Hossein Ashkooti2, Mohammad Mahmoud Moradi3
1) MSc Poultry Nutrition Graduate, Islamic Azad University, Mahabad Branch
2) MSc Poultry Nutrition Graduate, Islamic Azad University, Mahabad Branch
3) MSc Poultry Nutrition Graduate, Faculty of Agriculture, Urmia University
Ventilation
Always keep in mind that without sealing and blocking all the cracks in the walls and ceilings of the halls, one cannot expect to create proper ventilation and aeration conditions in the breeding halls. For this purpose, in order to ensure complete sealing of the hall, all the inlets except one of them that is slightly opened or the main door is slightly opened, and along with these mentioned items, a fan with a capacity of moving 18 square centimeters of air per minute should be turned on. And in the meantime, the air inlet pressure into the house should be about 37.5 Pascals (or .151 inches above water level) at the inlet opening. If the pressure recorded at the inlet is less than 25 Pascals, it indicates that the house is not properly sealed.
An important management point to consider is that during the first two weeks of rearing, no hot or cold air masses from the floor of the house should hit the lower limbs of the chicks, and for this purpose, the minimum flow rate of 3. meters per second at the floor of the house should not be exceeded.
To have the right air in the house and the right conditions, use the following table:
House Air Quality Guide
| Oxygen% | More than 19.6% | |
| Carbon dioxide CO2 | Less than 0.3% / ppm3000 | |
| Carbon dioxide | Less than 10ppm | |
| Ammonia gas | Less than 10ppm | |
| Visible dust | Less than 3.4 mg/m3 | |
| Relative humidity | 70% |
Important note: Never neglect the minimum ventilation rate and always consider it to improve the air in the house early in the growing season.
Increase maximum ventilation when the oxygen level is less than 19.6% and the CO2 level is above 3000ppm.
Minimum ventilation is controlled by two important factors:
Timer-controlled fans
Inlets controlled by air inlet pressure
Of course, it should be noted that both of these factors independently control the temperature of the house, separately and complementary to each other.
The timer installed on the house ventilation system should be set to provide a minimum change in the amount of incoming air equal to 12.5% of the house air volume. (Minimum ventilation should be able to provide 12.5% of the house air volume.) To do this, we should turn on the desired ventilation for 60 seconds to ensure that the air enters the house in the right amount and mixes with the warm air inside before it reaches the top of the chickens’ heads.
Inlets play a vital role in the volume of incoming air and the uniformity of the air entering the house.
Inlets should be properly and reliably sealed when installed in the side walls of the house.
In houses that are fully automated, the inlets should respond to the operation of the fans and adjust the air pressure entering the house.
The number of inlets, the number of fans, and their maximum displacement capacity for air discharge should be consistent with each other and both are calculated based on the width of the house.
In the early stages of the breeding period, it is necessary to open the number of inlets based on the experience of the individual (the number depends on the weather conditions), but the opening of this number of inlets should not exceed 5 centimeters (two fingers).
According to research, the temperature of the air entering the house increases as it approaches the ceiling.
