Revisiting litter management between flocks (Poultry Specialist)
(Editor’s note: Jennifer Timmons is an assistant professor for University of Maryland Eastern Shore.)
During the winter months, the manner in which litter is managed between flocks becomes even more important.
It is important to remember that the next flock begins as soon as the previous flock is moved out of the house.
The layout period is an important time for the litter to release moisture and ammonia and for the reduction of organisms that can cause disease.
As longer layout times are experienced, it is a good opportunity to take advantage of this time to enhance the performance of the next flock.
A longer layout can be beneficial for reducing many disease challenges. For example, in a survey conducted by Tablante and colleagues in 1999, it was reported that broiler farms that experienced an early respiratory disease challenge had a layout that was two days less compared to the layout period on broiler farms that reported no history of the disease.
In a more recent article, researchers from USDA-ARS reported that a layout of more than 14 days created unfavorable conditions for Salmonella.
In a report by Malone and Johnson in 2011, it is recommended to walk through the chicken houses soon after livehaul has left the farm to observe the litter and identify areas that may have been problems during the flock.
Note the location, character and depth of caked litter through the house. This will help to determine how deep to run the equipment when crusting out the litter.
The authors also reported that houses with proper airflow and good drinker management will have little cake underneath the drinker lines and no cake near the sidewalls.
Proper drinker management will limit the amount of cake under the drinker lines.
Improper airflow in houses can cause caking along the sidewalls.
If a lot of caking is found down the length of the sidewall, in the brood chamber, this may be due to poor airflow causing cold wet air to fall to the floor during brooding, condensation on concrete footers during cold weather or inadequate litter depth.
When caking is found in random spots along the sidewall, cold air is hitting the floor in just that caked area.
The authors suggest that this could be due to vents that are not closed tightly, air leaks along the footers, loss of insulation, improperly insulated evaporative cooling pads or poor drainage outside the house allowing water to seep inside the house.
If the litter is caked from sidewall to sidewall, proper humidity was not maintained during brooding.
This is typically from new litter, insufficient litter depth, and/or poor ventilation.
Observing the depth of the cake and where it is located in the house can be used as a tool to eliminate these issues during the next flock.
Another goal of the layout is to promote ammonia and moisture release from the litter.
It is recommended to close up houses as soon as possible after catch to preserve as much heat as possible.
Using the heat in the litter from the previous flock helps to reduce ammonia levels for the next flock.
This will also help to decrease fuel usage because less fuel will be required to pre-heat the house prior to chick placement. It is also important to keep in mind that as litter temperature increases during the pre-heat period a second release or purge of ammonia will occur.
This second ammonia purge should be completed before litter amendments are applied and prior to the arrival of the chicks. There are many opinions as to the amount of ventilation needed between flocks.
At the very least, some minimum ventilation is needed during layout to remove moisture and ammonia when people are working inside the chicken house.
During other times of the layout period, typically fans should be run during the hottest parts of the day.
However, houses may need to be ventilated more if the cake has been pulverized or windrowed between flocks because of higher ammonia levels released from the litter.
Crusting-out of the litter between flocks is still the most common litter management strategy used to prepare the litter for the next flock.
Other litter management techniques include pulverization and windrowing. No matter what litter management strategy is used between flocks it is important that it is done properly and started as soon after bird movement as possible.
When birds are out of the house, it is often the misconception that management of that house stops.
However, implementing proper litter management strategies and ventilation during the layout period often can have beneficial results when chicks are placed back on the farm.