Optimum Ventilation Capacity for Layer Houses

Abstract

A stochastic weather model was used in conjunction with a deterministic performance model of egg production. These two models were used to determine optimum ventilation rate capacities for layer houses, given four different climates (as reflected by monthly maximum outside temperatures), and two egg price scenarios. Stochastic simulations were conducted for 200 yr at expected maximum monthly average temperatures of 21, 23, 25, and 27 C. Optimum ventilation rates ranged from 3.75 m3/h per kilogram to at least 9.4 m3/h per kilogram depending upon flock placement date or confidence level desired. Net economic return increased by as much as $.263 per layer per year when 7.5 m3/h per kilogram was used instead of 3.75 m3/h per kilogram, in a warm climate. In addition, optimum ventilation capacity was reduced by 1.9 m3 h per kilogram if the price differential that existed between extra large and large eggs was eliminated. These findings suggest that optimal ventilation capacities are higher than those currently in common use, particularly in areas with a moderate climate.