Concentrations of Ammonia, Greenhouse Gases and Particulate Matters in Conventional Cage, Aviary, and Enriched Colony Laying-Hen Houses

Abstract

KeywordsIndoor air quality, ammonia, greenhouse gas, laying-hen, alternative hen housing Disciplines Agriculture | Bioresource and Agricultural Engineering CommentsResearch concerning comparative environmental impacts between conventional cage and emerging alternative laying-hen housing systems is relatively limited under US production conditions. As an integral part of the Coalition for Sustainable Egg Supply (CSES) project, a 27-month continual environmental monitoring (covering two single-cycle flocks) described in this paper quantifies the indoor gaseous and particulate matter (PM) concentrations, thermal environment, and housing ventilation rate (VR) for a conventional cage (CC) house, an aviary (AV) house, and an enriched colony (EC) house. Results show that indoor temperature and relative humidity (RH) in all three houses were well maintained through proper ventilation management and supplemental heat in wintertime (AV house only). Daily mean(±SD) indoor ammonia (NH3) concentrations were 4.3(±2.6) ppm for CC house, 7.1(±6.3) ppm for AV house, and 2.8(±1.8) ppm for EC house. The NH3 concentrations in the AV house were significantly higher than those in CC or EC house, and occasionally exceeded 25 ppm under cold weather conditions (ambient temperature <7.2°C). Daily mean(±SD) indoor carbon dioxide (CO2) and methane (CH4) concentrations were, respectively, 2153(±1058) and 11.1(±5.7) ppm for CC house, 2485(±1268) and 11.6(±5.5) ppm for AV house, and 2241(±1145) and 11.8(±5.9) ppm for EC house. The particulate matter (PM) concentrations in AV house were significantly higher than those in CC or EC house. Daily mean (±SD) concentrations of PM10 and PM2.5 were, respectively, 0.59(±0.16) and 0.035(±0.013) mg m-3 for CC house, 3.95(±2.83) and 0.410(±0.251) mg m-3 for AV house, 0.44(±0.18) and 0.056(±0.021) mg m-3 for EC house. Overall, indoor air quality of the EC house was comparable with that of the CC house; however, the AV house experienced poor indoor air quality, especially during cold weather, resulting from the presence of floor litter and hens activities on it. Therefore searching for mitigation practices to improve indoor air quality in AV housing system is needed.This conference proceeding is available at Iowa State University Digital Repository: http://lib.dr.iastate.edu/abe_eng_conf/396The authors are solely responsible for the content of this technical presentation. The technical presentation does not necessarily reflect the official position of the American Society of Agricultural and Biological Engineers (ASABE), and its printing and distribution does not constitute an endorsement of views which may be expressed. Technical presentations are not subject to the formal peer review process by ASABE editorial committees; therefore, they are not to be presented as refereed publications. Citation of this work should state that it is from an ASABE conference presentation. (Conference Name

Evaluating Draft EPA Emissions Models for Laying Hen Facilities

“…While enriched colony cages have been shown to provide better bird welfare metrics compared to cage-free environments, including vertical aviaries with litter-floor (Hardin et al, 2019;Janczak and Riber, 2015;Lay et al, 2011), recent retailer and supply chain pledges (Graber and Keller, 2020) and individual state mandates are driving a transition towards vertical aviaries for cage-free production. Challenges with vertical aviaries include lower bird density, which requires supplemental heating, reduced indoor air quality (Zhao et al, 2015a,b;Shepherd et al, 2015), and greater emissions of PM, NH 3 and greenhouse gases (Zhao et al, 2014). Both enriched colony and vertical aviary systems require a better understanding of NH 3 , and PM emissions as a key component to comply with the air emission practices for laying hen facilities.…”