Morgan D. Hayes

Environmental assessment of three egg production systems — Part II. Ammonia, greenhouse gas, and particulate matter emissions

As an integral part of the Coalition for Sustainable Egg Supply (CSES) Project, this study simultaneously monitored air emissions of 3 commercially operated egg production systems at the house level and associated manure storage over 2 single-cycle flocks (18 to 78 wk of age). The 3 housing systems were 1) a conventional cage house (CC) with a 200,000-hen capacity (6 hens in a cage at a stocking density of 516 cm2/hen), 2) an enriched colony house (EC) with a 50,000-hen capacity (60 hens per colony at a stocking density of 752 cm2/hen), and 3) an aviary house (AV) with a 50,000-hen capacity (at a stocking density of 1253 to 1257 cm2/hen). The 3 hen houses were located on the same farm and were populated with Lohmann white hens of the same age. Indoor environment and house-level gaseous (ammonia [NH3] and greenhouse gasses [GHG], including carbon dioxide [CO2], methane [CH4], and nitrous oxide [N2O]) and particulate matter (PM10, PM2.5) emissions were monitored continually. Gaseous emissions from the respective manure storage of each housing system were also monitored. Emission rates (ERs) are expressed as emission quantities per hen, per animal unit (AU, 500 kg live BW), and per kilogram of egg output. House-level NH3 ER (g/hen/d) of EC (0.054) was significantly lower than that of CC (0.082) or AV (0.112) (P < 0.05). The house-level CO2 ER (g/hen/d) was lower for CC (68.3) than for EC and AV (74.4 and 74.0, respectively), and the CH4 ER (g/hen/d) was similar for all 3 houses (0.07 to 0.08). The house-level PM ER (mg/hen/d), essentially representing the farm-level PM ER, was significantly higher for AV (PM10 100.3 and PM2.5 8.8) than for CC (PM10 15.7 and PM2.5 0.9) or EC (PM10 15.6 and PM2.5 1.7) (P < 0.05). The farm-level (house plus manure storage) NH3 ER (g/hen/d) was significantly lower for EC (0.16) than for CC (0.29) or AV (0.30) (P < 0.05). As expected, the magnitudes of GHG emissions were rather small for all 3 production systems. Data from this study enable comparative assessment of conventional vs. alternative hen housing systems regarding air emissions and enhance the U.S. national air emissions inventory for farm animal operations.

Heat and Moisture Production of Hy-Line Brown Hens in Aviary Houses in the Midwestern U.S.

Abstract. In considering hen housing systems, up-to-date heat and moisture production data are essential to producing properly designed and managed ventilation and supplemental heating systems. The aviary system is one housing type under consideration by egg producers. The aviary system has a much lower bird stocking density and thus more freedom of movement for the birds compared to conventional cage housing. This study was conducted to obtain baseline heat and moisture production values for Hy-Line Brown hens in such houses in the Midwestern U.S. House-level thermal environment, gaseous concentrations, and bird production performance of two commercially operated 50,000-hen aviary houses were continually monitored over a 19-month period. The two houses used similar management practices and Hy-Line Brown hens with a 20-week difference in age. Data were collected for a complete flock (17 to 83 weeks, no molt) in each house. Total heat production (THP) of the hens, house-level latent heat production (LHP) or moisture production (MP), house-level sensible heat production (SHP), and respiratory quotient (RQ) were determined from the monitored variables using indirect calorimetry and mass/energy balance, respectively. Variations in THP, LHP/MP, SHP, and RQ within the day were delineated. Results of the study showed mean (±SE) THP, house-level LHP, house-level SHP, and RQ values of 5.94(±0.09) W kg -1 , 1.83(±0.03) W kg -1 , 4.11(±0.08) W kg -1 , and 0.94(±0.01), respectively, for the aviary housing system. The new data will improve the design and operation of building ventilation, supplemental heating, and ultimately production efficiency of aviary housing systems. The THP and RQ data will also be useful to indirect determination of building ventilation rate using the carbon dioxide (CO 2 ) balance method.

Ammonia, Greenhouse Gas, and Particulate Matter Concentrations and Emissions of Aviary Layer Houses in the Midwestern USA

There has been an increased interest in alternative housing for laying hens in certain parts of the world, including the United States. Associated with the movement are many questions to be addressed concerning sustainability of such systems. This study continually quantifies concentrations and emissions of ammonia (NH3), carbon dioxide (CO2), methane (CH4), and particulate matters (PM10 and PM2.5) for two side-by-side aviary barns each housing 50,000 Hy-Line brown laying hens, located in the Midwestern US. The gaseous concentrations were continually monitored using a photoacoustic multi-gas analyzer, while the PM concentrations were measured with tapered element oscillating microbalances (TEOMs). Barn ventilation rate was determined through monitoring the operation time of ventilation fans that had been calibrated in-situ. Nineteen consecutive months of monitored data (June 2010 – Dec 2011) are analyzed and presented. Daily indoor NH3, CO2, CH4, PM10, and PM2.5 concentrations (mean ±SD) were 8.7 (±8.4) ppm, 1,636 (±1,022) ppm, 10.0 (±6.8) ppm, 2.3 (±1.6) mg/m3, and 0.25 (±0.26) mg/m3, respectively. The aerial emissions are expressed as quantities per hen, per animal unit (AU, 500 kg body weight), and per kg of egg output. Daily emission rates were 0.15 (±0.08) NH3, 75 (±15) CO2, 0.09 (±0.08) CH4, 0.11 (±0.04) PM10, and 0.008 (±0.006) PM2.5 g/bird. The results are compared to reported emission values for conventional (high-rise and manure-belt) US laying-hen housing systems. Data from this study provide baseline concentration and emission values from the aviary housing system in the Midwestern US.

Bioenergetics of Hy-Line Brown Hens in Aviary Houses

In considering hen-housing systems, applicable heat and moisture production values are essential to producing properly designed and managed ventilation and supplemental heating systems. The aviary system is one housing type under consideration by egg producers. The aviary system has a much lower bird stocking density and more freedom of movement compared to conventional cage housing. This study was conducted to obtain baseline heat and moisture production values for Hy-Line Brown hens in such barns in the Midwestern US. The study continually monitored the house-level thermal environment, air quality, and bird production performance of two commercially operated 50,000-hen aviary houses over a 19-month period. The two houses used similar management strategies and Hy-Line Brown hens with a 20-week difference in age. Data were collected for a complete flock (17-83 weeks, no molt) in each house. Total heat production (THP) of the hens, house-level moisture production (MP), house-level sensible heat production (SHP), and respiratory quotient (RQ) were determined from monitored variables using indirect calorimetry and mass/energy balance, respectively. Variations in THP, MP, SHP and RQ within the day were delineated. Results of the study showed the THP, house-level MP, house-level SHP and RQ values of 5.94 W/kg, 1.83 W/kg, 4.11 W/kg, and 0.94 for the aviary housing system. The new data are expected to improve the design and operation of building ventilation and supplemental heating system, and ultimately production efficiency of the aviary housing systems. The THP and RQ data will also prove useful to indirect determination of building ventilation rate using CO2 balance method.

Evaluating a New Shade for Feedlot Cattle Performance and Heat Stress

Heat stress in cattle results in decreased feed intake, lower daily gain, and potentially death in susceptible animals under intense conditions. A study was carried out during the summer of 2013 at the USDA-ARS U.S. Meat Animal Research Center feedlot evaluating the impact of shade on environmental conditions and cattle performance. A novel twotiered shade was used in half of the 14 pens, each holding 30 animals. The shades were designed to reduce solar heat load by 40% to 60% and to provide traveling shade across the pen, providing varied amounts of shade area as well as varied solar reduction potential. The objective of this study was to determine if the shade was effective at improving performance (evaluated as average daily gain, feed intake, and feed to gain ratio) and reducing environmental conditions that cause heat stress. A group of mixed-breed cattle with varied genetics including both Bos taurus and Bos indicus were selected, penned on the basis of sex, and blocked by color. Production parameters of pen feed usage were measured daily, and individual body weights were taken monthly. Environmental conditions including air temperature, relative humidity, wind speed, ground temperature, and black globe temperature with and without shade were measured. Solar load on the pens was reduced when shade was provided, with both ground temperature and black globe temperature showing reductions. Cattle showed nominally better performance; however, no significant differences were found in gain or feed intake. Panting scores were significantly lower with shade provided; slopes of cattle respiration rate versus ambient temperature were significantly lower with shade during the afternoon period.

Electricity and Fuel Use of Aviary-Laying Hen Houses in the Midwestern United States

Abstract. There is a growing interest in and movement toward alternative housing systems for laying hens. Associated with the movement are many questions to be addressed concerning sustainability of these systems. This study quantified electricity and propane use in two side-by-side aviary houses each with a holding capacity of 50,000 laying hens, located in Iowa. Electricity use was partitioned into different housing components, including ventilation, lighting, and manure-drying. Results indicate that electricity consumption for ventilation had the most variation, accounting for 30% of the total electrical demand in the summer but less than 5% in the winter. Manure-drying blowers ran continuously throughout the flock, using approximately 345 kWh d -1 and accounting for approximately 51% of the annual electrical demand. Ventilation efficiency of the exhaust fans was approximately 25.5 m 3 (h-W) -1 (15 CFM W -1 ) at static pressure of 12.5 Pa (0.05 in. water column). Over the 15-month monitoring period, both houses had an average electricity cost of 3.0 cents per kg (or 2.3 cents per dozen) eggs produced (based on the rate of

Electricity and fuel usage of aviary laying-hen houses in the Midwestern United States.

0.09 kWh -1 ). The propane use was minimal, less than 425 L (112 gal) in one year or 0.6 mL per kg (0.4 L per dozen) eggs produced.

Comparison of Ammonia Emissions from Poultry Houses Based on Diurnal Integration vs. Daily Means of Gas Concentration and Building Ventilation Rate

Recently, there has been much interest in and movement toward alternative housing systems for laying hens. Associated with the movement are many questions to be addressed concerning sustainability of such systems. This study quantifies electricity and propane usage in two side-by-side aviary hen houses each holding 50,000 laying hens, located in Iowa, USA. Electricity usage was also partitioned into different housing components, including ventilation, lighting, and manure-drying. Electricity for ventilation is most variable in that it was the largest of all the components with 60% of the total electric energy in summer but only approximately 5% in winter. The mechanical ventilation efficiency was approximately 25.5 m3/(hr-Watt) (15 CFM per Watt) at static pressure of 12.5 Pa (0.05 inch water column). The continuously running manure-drying blowers accounted for the largest proportion of electricity use in winter with approximately 350 kWh daily consumption. Over the 15-month monitoring period, both houses had an average electricity cost of 3.6 cents per kg of egg produced (based on the rate of

An Evaluation of Pullet and Young Laying Hen Ammonia Aversion Using a Preference Test Chamber

0.09/kWh). The fuel usage was minimal (less than 425 liters of propane in one year), although the winter weather during the monitoring period was milder than the historical climatic conditions.

Utilizing Thermal Imaging to Locate Blood Flow in the Bovine Ear

Quantification of aerial emissions from animal feeding operations (AFOs) requires the knowledge of both concentration of the constituent of interest and the ventilation rate (VR) through the emitting source. Daily emissions can be and are normally determined from diurnal integration of frequent measurements, referred to as the diurnal integration method (DIM), but is resource intensive. Alternatively, daily emission may be more economically estimated from daily means of concentration and VR, referred to as diurnal means method (DMM). In this study, DMM was compared with DIM in determining daily ammonia (NH3) emissions from mechanically ventilated laying-hen, turkey and broiler houses under U.S. production conditions. Results show that deviations in daily NH3 emissions between DMM and DIM methods ranged from as small as < 3% (e.g., for medium age turkey under both cold and warm weather conditions) to as high as 98% (e.g., broiler houses in summer). Deviations were related with coefficient of variation (CV) of VR or NH3 concentration, although prediction of the deviation using CV of VR and/or NH3 concentration alone will likely not produce reliable results. The study suggests that caution must be taken when using DMM to estimate daily NH3 emissions from poultry houses under typical US production conditions.