Poultry Engineering, Economics & Management
Newsletter of the
National Poultry Technology Center, Auburn University
Critical Information for Improved Bird Performance Through Better House and Ventilation System Design, Operation and Management
Produced in cooperation with the U.S. Poultry & Egg and Alabama Poultry & Egg Associations Issue No 67, August 2010
Tunnel Ventilating Younger Birds
By Jim Donald, Jess Campbell, Berry Lott and Gene Simpson*
The summer has been brutally hot in most parts of the poultry belt. Growers with properly designed and maintained tunnel ventilated houses are much better equipped to handle the hot weather. Those with conventional houses can really struggle, especially as the flock nears market age. Tunnel ventilation technology has matured and been used in the US poultry belt for about 25 years. Most growers and managers have a pretty good feel of how to manage tunnel houses as birds get bigger. However, many growers and managers are less sure of how to keep small younger birds comfort- able in extremely hot weather. Many of the calls we have been getting lately are from growers ask- ing something like, “If the temperature is at or above 98-100°F outside and birds are only a few days old, what is the best way to get them comfortable in a tunnel house that has 6-inch cool cell pads?”
Tunnel ventilation for very young birds does need to be managed differently from the way we tunnel ventilate older birds. This is why one of the old rules of thumb, “Do not tunnel ventilate birds until they are 21 days old,” came into being. This rule of thumb has been around a long time. It came about to keep managers from doing more harm than good with tunnel ventilation on small birds and it came about before we had in place the modern equipment and controls to run a tunnel house. It also came about in an era when the industry was still early on in the learning curve of understanding and managing tunnel ventilation. But experience has taught us that if we understand the basic prin- ciples of bird heat transfer when using tunnel ventilation and apply these principles correctly, tunnel can be a very valuable tool to make any age bird comfortable.
One old rule of thumb said, “Do not tunnel ventilate birds until they are 21 days old.” But experience has taught us that if we understand the basic principles of bird heat transfer when using tunnel ventilation and apply these principles correctly, tunnel can be a very valuable tool to make any age bird comfortable.
The key point to keep in mind is that just about anything you do to increase air movement or reduce air temperature will have greater effect on young birds than on older birds.
*Berry Lott is a retired poultry research scientist, formerly with the USDA-ARS Poultry Research Unit, Mississippi State, MS. All other authors are with the National Poultry Technology Center at Auburn University.