Table 5.

Summary of house-level, manure storage, and farm-level daily emission rates of ammonia (NH₃), carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), and particulate matter (PM₁₀ and PM_2.5) for the conventional cage (CC), aviary (AV), and enriched colony (EC) housing systems over the 27 mo monitoring period.

		Housing system
Gas or PM	Source	Conventional cage (CC)			Aviary (AV)			Enriched colony (EC)
		g/hen/d	g/(kg egg)	% of total	g/hen/d	g/(kg egg)	% of total	g/hen/d	g/(kg egg)	% of total
NH3	House	0.082b	1.62	28	0.112a	2.19	40	0.054c	0.99	31
	Manure storage	0.21a	4.00	72	0.18a	3.52	60	0.11b	2.02	69
	Farm	0.29	5.52	100	0.30	5.88	100	0.16	2.94	100
CO2	House	68.3b	1,300	89	74.0a	1,450	90	74.4a	1,365	91
	Manure storage	8.1	154	11	8.0	157	10	7.1	130	9
	Farm	76.4	1,454	100	82.0	1,607	100	81.5	1,495	100
CH4	House	0.07	1.33	70	0.07	1.37	70	0.08	1.47	80
	Manure storage	0.03	0.57	30	0.03	0.59	30	0.02	0.37	20
	Farm	0.10	1.90	100	0.10	1.96	100	0.10	1.84	100
N2O	House	—	—	—	—	—	—	—	—	—
	Manure storage	0.03	0.57	—	0.03	0.59	—	0.01	0.18	—
	Farm	0.03	0.57	—	0.03	0.59	—	0.01	0.18	—
PM10	House	0.0157b	0.299	100	0.1003a	1. 909	100	0.0156b	0.297	100
	Manure storage	—	—	—	—	—	—	—	—	—
	Farm	0.0157	0.299	100	0.1003	1. 909	100	0.0156	0.297	100
PM2.5	House	0.0009b	0.018	100	0.0088a	0.168	100	0.0017b	0.032	100
	Manure storage	—	—	—	—	—	—	—	—	—
	Farm	0.0009	0.018	100	0.0088	0.168	100	0.0017	0.032	100

Means of gaseous or particulate matter emission rates of the housing systems with different superscript letters significantly differ (P < 0.05).