Shepherd T A, Zhao Y, Li H, Stinn J P, Hayes M D, Xin H
Department of Agricultural and Biosystems Engineering, Iowa State University, Ames.
Department of Animal and Food Sciences, University of Delaware, Newark.
Poult Sci. 2015 Mar;94(3):534-43. doi: 10.3382/ps/peu075.
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.
作为可持续蛋品供应联盟（CSES）项目的一个组成部分，本研究在两个单周期鸡群（18至78周龄）期间，对3个商业化运营的蛋鸡生产系统的鸡舍层面空气排放以及相关粪便储存情况进行了同步监测。这3种鸡舍系统分别为：1）一座存栏量为20万只母鸡的传统笼养鸡舍（CC）（每笼6只母鸡，饲养密度为516平方厘米/只）；2）一座存栏量为5万只母鸡的富集笼养鸡舍（EC）（每个鸡群60只母鸡，饲养密度为752平方厘米/只）；3）一座存栏量为5万只母鸡的开放式鸡舍（AV）（饲养密度为1253至1257平方厘米/只）。这3座鸡舍位于同一农场，饲养的是同龄的罗曼白母鸡。对室内环境、鸡舍层面的气体（氨气[NH₃]和温室气体[GHG]，包括二氧化碳[CO₂]、甲烷[CH₄]和氧化亚氮[N₂O]）以及颗粒物（PM10、PM2.5）排放进行了持续监测。还对每个鸡舍系统各自粪便储存处的气体排放进行了监测。排放率（ERs）以每只母鸡、每动物单位（AU，500千克活体重）和每千克鸡蛋产量的排放量来表示。富集笼养鸡舍（EC）的鸡舍层面氨气排放率（克/只母鸡/天）为0.054，显著低于传统笼养鸡舍（CC）的0.082或开放式鸡舍（AV）的0.112（P<0.05）。传统笼养鸡舍（CC）的鸡舍层面二氧化碳排放率（克/只母鸡/天）为68.3，低于富集笼养鸡舍（EC）和开放式鸡舍（分别为74.4和74.0），而甲烷排放率（克/只母鸡/天）在所有3种鸡舍中相似（0.07至0.08）。开放式鸡舍（AV）的鸡舍层面颗粒物排放率（毫克/只母鸡/天），基本上代表农场层面的颗粒物排放率，显著高于传统笼养鸡舍（CC）（PM10为15.7，PM2.5为0.9）或富集笼养鸡舍（EC）（PM10为15.6，PM2.5为1.7）（P<0.05）。农场层面（鸡舍加粪便储存）的氨气排放率（克/只母鸡/天），富集笼养鸡舍（EC）为0.16，显著低于传统笼养鸡舍（CC）的0.29或开放式鸡舍（AV）的0.30（P<0.05）。正如预期的那样，所有3种生产系统的温室气体排放量都相当小。本研究的数据有助于对传统与替代鸡舍系统的空气排放进行比较评估，并完善美国农场动物养殖的国家空气排放清单。
