Written by: Dr. Jacquie Jacob, University of Kentucky
In relation to poultry production, lime is a generic term used to refer only to the manufactured forms of lime. These forms of lime are quicklime, which is calcium oxide (CaO), and hydrated lime, which is calcium hydroxide (Ca(OH)2). The terms whitewash and, less commonly, milk of lime are used to refer to a suspension of hydrated lime in water. (For the purposes of this article, the term lime does not include agricultural lime, which is crushed limestone. Agricultural lime should not be used in poultry houses.)
The use of lime in poultry production can have several effects.
The routine of cleaning and disinfecting equipment and the poultry house between production cycles is key to controlling disease. In addition to the cleaning and disinfecting process, producers can use lime in poultry houses to control pathogens (and reduce fly problems). According to current research, lime is effective at controlling the following poultry diseases:
University of Georgia researchers found that adding 15 lbs. of quicklime to each 100 pounds of used litter and turning the litter every other day for 10 days reduced bacterial loads in the litter with no adverse effects on broilers placed in the house after the 10-day preparation period. Researchers conducting a multiple-trial study using turkey litter, however, encountered contradictory results. In the first trial, inclusion of up to 5% lime in turkey litter improved poult performance. In a subsequent trial, the inclusion of 5% lime in the litter did not improve poult performance.
Producers should exhibit great care when using lime in poultry houses. Lime is caustic to organic matter and destroys debris in addition to pathogens. Lime also burns the footpads of birds if it is left on the ground or floor. It is important to take animals out of an area before treating the area with lime. Also, working with lime is extremely dangerous. Dust inhaled or exposed to the eyes can cause severe burning of the eyes and mucous membranes. When using lime, poultry producers should wear personal protective equipment.