How to manage air velocity to enhance broiler performance


Fast travelling air increases wind chill to the birds reducing its actual temperature that should have been experienced. Due to this, birds tend to group together which may affect litter quality especially during winter season. On the other hand, slow travelling air causes a build-up of heat, moisture and hazardous gases such as carbon dioxide and ammonia within the house. This will directly impact quality of the litter during winter season and have a dramatic impact on livability, particularly during the hotter months of the year. In both cases, performance will be affected, as the birds are being pushed outside of their comfort zone.

In environmentally controlled houses, house closed firmly is an essential consideration for achieving a good, reliable negative pressure. This means that all cracks, holes and any poorly fitting panels and doors should be sealed, to ensure that air only enters where it is meant to, such as through house side wall or ceiling inlets.

Steps to check house closed firmly:

  • All the doors, inlets and fans must be closed.
  • Turn off any lights that are on and not required.
  • Wait until your eyes acclimatize to the dark and look around the house.
  • Any unwanted cracks and holes can easily be seen, as light will ‘leak’ in through them.

A negative pressure must be available in a house to control and keep up air speed. The most straightforward and slightest costly approach to seal these regions is with an expandable foam product. To test the effectiveness of the sealing procedure, it is a good idea to use a pressure meter to check the pressure of the house, both before and after sealing.

To do this:

Set up the pressure meter following the usage instructions provided with the equipment, and ensure that the outside pressure pipe is correctly situated.

Close all entryways and inlets.

Switch on the fans.

Record the pressure reading.

Repeat this procedure when all sealing has been finished and compare the two readings.

House pressure ought to achieve at least 0.15 inches of water segment or 37.5Pa subsequent to fixing.

Air Speed, Direction and House Pressure

The bird’s daily performance is strongly influence by the direction of the air current and is linked with house pressure, house framework, and inlet design and opening size. The air current flow that enters the poultry house is mostly dependent on design and opening space of the inlet.

A channel that is completely open may cause make air drop straightforwardly on top of the birds, pushing them outside their thermo-neutral zone. However, inlets that are not sufficiently open will build the house weight and velocity, bringing air into the house too rapidly, and not permitting it to blend viably, especially amid least ventilation. Opened vents ought to be dispersed similarly down the length of the house.  For older birds, and as ventilation rates increase (more fans turned on), inlets must be opened more extensive, however satisfactory negative pressure must be kept up.