Monitoring total endotoxin and (1→3)-β-d-glucan at the air exhaust of concentrated animal feeding operations

Figures & data

Table 1. Summary of the sampling campaign

Animal	Operation Type	Location	No. of Buildings^1	No. of Visits^2
Swine	Gestation	Illinois	3	9
	Farrowing	Illinois	3	9
	Weaning	Illinois	3	8^3
	Finishing	Illinois	3	9
Poultry	Manure-belt laying hen	Illinois and Indiana	3	9
	Tom turkey	Illinois	3	9
Total			18	53
Notes: ^1For each operation type, the three buildings selected were located at different animal farms. ^2Only one TSP sample was collected from each field trip for bioaerosol analyses. ^3One farm closed down before the last visit, thus, the hot season samples were not collected.

Table 2. General information of the visited animal feeding operations

Operation Type	Site	Barn size (m)			No. of Animals	Floor Type	Manure Storage	Feeding System	Ventilation Fans^1
		L	W	H
Farrowing	A	15	6	2.4	26^2	Partially slatted	Shallow pit	Dry feeder	0.3 m ×1; 0.6 m × 1; 0.9 m ×1
	B	18	8	2.4	28^2	Partially slatted	Shallow pit	Dry feeder	0.3 m ×1; 0.6 m × 1; 0.9 m ×1
	C	15	13	2.4	52^2	Partially slatted	Shallow pit	Dry feeder	0.9 m × 3; 0.6 m × 2
Gestation	D	185	28.6	2.5	2350–2400	Fully slatted	Deep pit	Wet feeder	1.2 m × 16; 0.5 m × 30
	E	150	28.6	2.5	2000–2064	Fully slatted	Deep pit	Wet feeder	1.2 m × 14
	F	168	25.8	2.5	2050–2500	Fully slatted	Deep pit	Wet feeder	1.2 m × 18
Weaning	G	95	16	2.4	2350–3890	Partially slatted	Shallow pit	Dry feeder	1.2 m × 7; 0.9 m × 6
	H	18	12	2.7	906–949	Partially slatted	Shallow pit	Dry feeder	0.9 m × 2; 0.6 m × 2; 0.3 m × 2
	I	18.2	12.2	2.4	500–750	Partially slatted	Shallow pit	Dry feeder	0.6 m × 2; 0.23 m × 2
Finishing	J	65	12	2.4	2500–2700	Fully slatted	Deep pit	Wet feeder	1.2 m × 4; 0.9 m ×1; 0.4 m × 4
	K	56	24	2.2	2500–3060	Fully slatted	Deep pit	Wet feeder	1.2 m × 2; 0.6 m × 22
	L	67	16	2.5	1134–2380	Fully slatted	Deep pit	Wet feeder	1.2 m × 2; 0.9 m × 1; 0.4 m × 8
Tom turkey	M	91	18	3.6	4000–4500	Wood shaving bedding	Bedding	Hanging feeder	Natural ventilation
	N	76	24.3	3.6	5100–6000	Wood shaving bedding	Bedding	Hanging feeder	Natural ventilation
	O	120	20	3.6	4500–5000	Wood shaving bedding	Bedding	Hanging feeder	Natural ventilation
Manure-belt laying hen	P	140	21	12	243,835–262,300	Concrete	Manure belt	Hopper feeder	1.4 m ×88; 1.2 m ×4
	Q	180	28	12	436,000–449,800	Concrete	Manure belt	Hopper feeder	1.4 m ×154
	R	108	18	6.0	74,000–75,600	Concrete	Manure belt	Hopper feeder	1.2 m ×26
Notes: ^1Fans highlighted with underline are pit fans. ^2Only sows were counted. Each sow farrowed 8–12 piglets.

Table 3. Summary of measured TSP concentrations based on animal operation type^1,2

	TSP Concentration (mg/m^3)
Operation Type	Mean	SD	GM^3	GSD	Range
Farrowing (N = 9)	0.95	0.66	0.76^a	2.07	0.24–2.27
Gestation (N = 9)	0.76	0.37	0.67^a	1.71	0.30–1.39
Weaning (N = 8)	1.70	1.41	1.16^ab	2.91	0.14–4.59
Finishing (N = 9)	1.76	1.10	1.38^ab	2.23	0.32–3.50
Manure-belt laying hen (N = 9)	2.51	1.56	2.12^ab	1.87	1.00–5.58
Tom turkey (N = 9)	5.15	4.55	3.91^b	2.18	1.49–15.61
Notes: ^1TSP concentrations for each animal operation type were combined over all seasons. ^2The Shapiro-Wilk test revealed that the measured concentration data were not normally distributed, but rather followed a lognormal distribution. Accordingly, geometric mean (GM) and geometric standard deviation (GSD) were presented. ^3Within a column, values labeled with the same letter were not significantly different (P > 0.05).

Table 5. Summary of measured total (1→3)-β-glucan concentrations based on animal operation type¹

	Concentration in Dust (ng/mg dust)				Airborne Concentration (ng/m^3)
Operation Type	Mean	SD	GM^2	GSD	Mean	SD	GM^2	GSD	Range
Farrowing (N = 9)	25.2	21.4	15.6^a	3.24	21.2	20.2	12.5^a	3.50	2.4–50.7
Gestation (N = 9)	34.3	19.4	26.6^a	2.41	25.2	20.2	17.2^ab	2.71	3.7–50.8
Weaning (N = 8)	20.0	16.5	14.0^a	2.59	34.9	48.4	16.3^ab	3.58	3.8–140.1
Finishing (N = 9)	31.9	49.1	17.6^a	2.80	32.7	22.0	24.3^ab	2.62	3.9–65.0
Manure-belt laying hen (N = 8)^3	56.1	50.0	35.4^a	3.07	106.7	98.3	63.8^b	3.32	11.4–272.4
Tom turkey (N = 9)	28.0	27.5	16.3^a	3.47	121.0	173.4	63.5^b	3.26	10.0–537.9
Notes: ^1(1→3)-β-d-Glucan concentrations for each animal operation type were combined over all seasons. ^2Within a column, values labeled with the same letter were not significantly different (P > 0.05). ^3One TSP sample was lost during centrifuging.

Table 4. Summary of measured total endotoxin concentrations based on animal operation type¹

	Concentration in Dust (EU/mg dust)				Airborne Concentration (EU/m^3)
Operation Type	Mean	SD	GM^2	GSD	Mean	SD	GM^2	GSD	Range
Farrowing (N = 9)	735	857	439^a	2.79	508	617	334^a	2.47	98–2099
Gestation (N = 9)	1027	1007	622^a	2.96	510	317	419^ab	1.98	164–991
Weaning (N = 8)	1176	840	875^a	2.38	1971	2816	1017^bc	3.30	217–8702
Finishing (N = 9)	1204	872	929^a	2.17	1508	978	1285^bc	1.51	693–3588
Manure-belt laying hen (N = 9)	672	1333	287^a	3.01	2008	4092	607^ab	4.17	148–12,661
Tom turkey (N = 9)	1154	949	780^a	2.89	5460	7377	3044^c	3.09	593–23,157
Notes: ^1Endotoxin concentrations for each animal operation type were combined over all seasons. ^2Within a column, values labeled with the same letter were not significantly different (P > 0.05).

Table 6. Summary of measured TSP, total endotoxin, and total (1→3)-β-glucan concentrations in different seasons¹

				Total Endotoxin				Total (1→3)-β-d-Glucan
		TSP Conc. (mg/m^3)		Airborne Conc. (EU/m^3)		Conc. in dust (EU/mg)		Airborne Conc. (ng/m^3)		Conc. in dust (ng/mg)
Animal	Season	GM^2	GSD	GM^2	GSD	GM^2	GSD	GM^2	GSD	GM^2	GSD
Poultry	Cold	5.40^a	2.18	1,581^a	4.32	293^a	2.21	93.2^a	3.59	20.2^a	3.11
	Mild	3.34^ab	1.75	1,519^a	4.31	454^a	3.69	57.9^a	1.72	16.4^a	2.51
	Hot	1.58^b	1.43	1,070^a	2.81	675^a	2.69	68.0^a	1.68	51.6^a	1.53
		P = 0.020^3		P = 0.884		P = 0.402		P = 0.761		P = 0.147
Swine	Cold	1.58^a	1.85	764^a	3.24	484^a	2.38	17.9^a	3.40	11.3^a	2.44
	Mild	1.22^a	1.64	660^a	2.48	642^ab	2.39	23.9^a	2.20	19.6^ab	2.24
	Hot	0.45^b	2.00	590^a	2.21	1,308^b	2.07	13.8^a	2.58	30.6^b	2.31
		P = 0.002		P = 0.801		P = 0.027		P = 0.516		P = 0.047
Notes: ^1The Shapiro-Wilk test revealed that the measured concentration data followed a lognormal distribution. Thus, the concentrations data were presented with geometric mean (GM) and geometric standard deviation (GSD). ^2Within a column, values labeled with the same letter were not significantly different (P > 0.05). ^3The P value offered by the ANOVA test was used for determining the significance of seasonal effects.

Figure 1. Effect of ambient temperature on total endotoxin and (1→3)-β-d-glucan concentrations. Daily average ambient temperature was obtained from the nearest weather station (18.7 ± 7.6 miles from the visited animal farms).

Figure 2. (A) Indoor and ambient average temperatures during different seasons (all animal buildings combined), and (B) correlation between indoor and ambient average temperatures (all buildings combined). Indoor air temperature at the sampling point was monitored (∼1.5 m over the floor) during a field trip and averaged over the sampling period (∼24 hr). The measured indoor air temperature did not represent the temperature in the feed and manure storage zones.