Evaluation of the effects of maintaining a moderate humidity (50–60%) and increased air movement on litter moisture and footpad health in a commercial broiler house

Abstract

High litter moisture (>25%) strongly correlates with higher ammonia and increased footpad lesions. Although there are methods to help reduce the occurrence of high litter moisture, such as ventilation and proper drinker management, these methods need to evolve due to increasing consumer demands and more stringent animal welfare guidelines. A potentially cost-effective method may be ventilating houses to maintain a moderate RH level (60% or lower) and increasing the amount of air movement (150 ft/min) over the litter surface through circulation fans. This field study examined the possible effects of this combination on litter moisture and footpad health. The combination (TRT) had the greatest impact during the first 3 wk of a flock. The mean litter moisture was below 25% during this period in TRT houses. While litter moisture in the control (CTL) houses (no circulation fans- same RH) was 30% or greater. During the first 21 d, in 3 out of the 4 study flocks, less than 10% of birds had signs of lesions in the TRT house compared to up to 29% of birds in the CTL house. At the end of the flock, birds in the CTL house had, on average, a 23% higher rate of severe lesions than birds in the TRT house. These findings suggest moderate RH and supplemental air movement over the litter surface (150 ft/min) can benefit litter moisture control and footpad health.