Table 3.

House-level daily emission rates (ERs; mean and SE) of ammonia (NH₃), carbon dioxide (CO₂), methane (CH₄), and particulate matter (PM₁₀ and PM_2.5) for the conventional cage (CC), aviary (AV), and enriched colony (EC) houses expressed in different units for each of the 2 flocks.

		Housing system
Gas or PM	Unit	Conventional cage (CC)		Aviary (AV)		Enriched colony (EC)
		Flock 1	Flock 2	Flock 1	Flock 2	Flock 1	Flock 2
NH3	g/hen/d	0.097	0.068	0.136	0.088	0.059	0.049
	SE	(0.010)	(0.004)	(0.011)	(0.006)	(0.006)	(0.004)
	g/AU/d	31.2	20.7	43.4	28.1	19.3	15.6
	SE	(3.22)	(1.22)	(3.51)	(3.22)	(1.97)	(1.27)
	g/(kg egg)	1.90	1.26	2.69	1.71	1.10	0.88
	SE	(0.20)	(0.07)	(0.22)	(0.12)	(0.11)	(0.07)
CO2a	g/hen/d	68.5	68.1	72.5	75.6	74.9	73.9
	SE	(0.85)	(0.57)	(0.93)	(1.68)	(1.19)	(1.02)
	g/AU/d	22,054	20,750	23,133	24,169	24,557	23,550
	SE	(274)	(174)	(297)	(537)	(390)	(325)
	g/(kg egg)	1,341	1,261	1,434	1,468	1,400	1,331
	SE	(17)	(11)	(18)	(33)	(22)	(18)
CH4	g/hen/d	0.09	0.07	0.10	0.05	0.11	0.05
	SE	(0.007)	(0.004)	(0.007)	(0.003)	(0.008)	(0.005)
	g/AU/d	29.0	21.3	31.9	16.0	36.1	15.9
	SE	(2.25)	(1.22)	(2.23)	(0.96)	(2.62)	(1.59)
	g/(kg egg)	1.8	1.3	2.0	1.0	2.1	0.9
	SE	(0.14)	(0.07)	(0.14)	(0.06)	(0.15)	(0.09)
PM10	mg/hen/d	16.9	14.5	87.6	113.0	13.9	17.3
	SE	(1.02)	(0.90)	(3.92)	(5.07)	(0.66)	(0.90)
	g/AU/d	5.4	4.4	28.0	36.1	4.6	5.5
	SE	(0.33)	(0.27)	(1.25)	(1.62)	(0.22)	(0.29)
	g/(kg egg)	331	268	1,732	2194	260	312
	SE	(20)	(17)	(78)	(98)	(12)	(16)
PM2.5	mg/hen/d	1.0	0.9	8.6	9.1	1.5	1.9
	SE	(0.24)	(0.14)	(0.32)	(0.27)	(0.10)	(0.15)
	g/AU/d	0.32	0.27	2.74	2.91	0.49	0.61
	SE	(0.08)	(0.04)	(0.10)	(0.09)	(0.03)	(0.05)
	g/(kg egg)	19.6	16.7	170	177	28.0	34.2
	SE	(4.70)	(2.59)	(6.3)	(5.2)	(1.87)	(2.70)

AU = animal unit = 500 kg live body mass.

^aIncludes CO₂ contributions from animal respiration (majority) and CO₂ production from manure (minor).