In addition to the correct temperature humidity, proper ventilation needs to be considered. Ventilation distributes heat throughout the house and maintains good air quality in the brooding area.
As chicks are more susceptible to air quality issues than are older birds, ammonia levels that produce a limited effect on a 7-week-old flock can reduce body weight gains of 7-day-old chicks by 20%. Ammonia levels should be kept below 10 ppm at all times.
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The Normal Way to Note Ammonia Level is, you must not feel irritation while breathing and irritation in Eyes. If you feel any irritation, it mean Ammonia and other Gases are on Peak & Immediately give emphasis on Ventilation by opening Plastic Curtain in Winter by Giving space from Upside but on the same time ideal temperature must not be compromised as per required temperature. Giving fresh air from other empty part of poultry shed is also considered good.
Air Quality Guidelines
Oxygen % Greater than 19.6 %
Carbon Dioxide Less Than 0.3 %/3,000 ppm
Carbon Monoxide Less Than 10 ppm
Ammonia Less Than 10 ppm
Relative Humidity Less Than 45-65 %
Dust in Air Less Than 3.4 mg/m3