Poultry encyclopedia · NEXTEKCI School · Farm equipment
Thermometer and thermo-hygrometer
Small instruments that measure air temperature and humidity at bird height, day and night. A min-max thermometer tells you what happened during the night. Essential during brooding, they are always read with the chicks in view.
Key facts
- Position
- At bird height, in the centre of the brooding area
- Days 1 to 3
- 32 to 34 °C under the brooder, 28 to 30 °C in the rest of the area
- After 14 days
- Lower by 2 to 3 °C per week
- 24-hour variation during brooding
- No more than 2 °C
- Air humidity
- 45 to 65%
- Readings
- Morning and evening, written on the record sheet
What they are for
A min-max thermometer remembers the lowest and highest temperatures since it was last reset: in the morning it tells you whether the chicks were cold during the night. A thermo-hygrometer shows air temperature and humidity at a glance.
This small equipment costs little compared with the house, but it is what lets you spot a problem in time.
Where to place them
At bird height, not up in the air: during brooding, at chick level in the centre of the brooding area, and under the edge of the brooder to check floor heat. A thermometer hung high up gives the farmer’s temperature, not the chicks’.
Keep it out of direct sun, away from contact with the metal roof or a hot wall, and not right above the heat source.
Values to aim for
At chick height: 32 to 34 °C under the brooder on days 1 to 3 (28 to 30 °C in the rest of the area), 30 to 32 °C on days 4 to 7, 28 to 30 °C on days 8 to 14, then 2 to 3 °C lower each week. During brooding, the temperature should not vary by more than 2 °C over 24 hours.
Air humidity is ideally between 45 and 65%. In rainy weather, high humidity often goes with wet litter.
Reading the figure alongside the birds
Always look at the chicks before reading the thermometer: huddled under the heat, they are cold; pressed against the edges with beaks open, they are too hot; evenly spread, all is well. If the figure and the chicks disagree, the chicks are right: look for a draught or a badly placed thermometer.
Write the morning and evening temperatures on the house record sheet, and reset the min-max thermometer after each morning reading.
Care and choice
Wipe off the dust regularly, keep the instrument away from water, and compare it from time to time with a second thermometer: an instrument that drifts leads to bad decisions. Choose a model that is readable from a distance, with a minimum and maximum memory; for a battery-powered unit, keep a spare battery.