Predictive model of laying hen performance to air temperature and evaporative cooling

A model for predicting layer performance as a function of air temperature was developed. Evaporative cooling as an environmental control management option was modeled as part of a general heat balance model that predicted building inside air temperature. The evaporative cooling model included the effects of daily variation in dry bulb temperature, the evaporative efficiency of the system, and the number of hours per day the system was operated. The layer model predicted several variables of interest, including egg production, feed, fuel and electricity costs, and mortality, which are used to predict the net return from the house, i.e. egg value minus all direct production costs. The model was applied to predict the effects of evaporative cooling in a cool climat using deterministic weather data as an example of the utility of the model.