TABLE 3.

PCR hybridization assay based on M. paratuberculosis-specific IS900 for manure treatment samples

Treatment	Optical density (recorded at 450 mm) of hybridization reactiona,b on day:
	0	3	7	14	28	56	175
DM-SD-55	2.4 ± 0.2a	3.1 ± 0.4a	2.6 ± 0.3b	2.6 ± 0.2a	1.5 ± 0.4a	1.3 ± 0.4a,c
DM-ST-55	2.3 ± 0.1a,b	3.2 ± 0.1a	3.0 ± 0.2a,c	2.5 ± 0.2a	2.0 ± 0.2a,b	0.8 ± 0.5a
DM-SD-25	2.4 ± 0.2a	3.2 ± 0.1a	3.1 ± 0.1a	2.6 ± 0.2a	2.4 ± 0.4b,c	3.0 ± 0.1b
DM-ST-25	2.3 ± 0.1a,b	3.3 ± 0.1a	2.5 ± 0.1b	2.5 ± 0.0a	2.6 ± 0.1b,c	2.8 ± 0.1b
DM-L-RT	2.1 ± 0.0b	3.3 ± 0.1a	2.7 ± 0.2b,c	1.8 ± 0.6b	0.9 ± 0.4d	2.0 ± 0.8c	0.6 ± 0.2
M. paratuberculosis suspensionc	3.00	3.01	3.37	3.03	3.00	3.00	1.44
Uninoculated manure	0.7 ± 0.2	1.3
M. paratuberculosis-negative manure (negative control)	0.08	0.07	0.09	0.07	0.10	0.12	0.07
PCR blank	0.05	0.06	0.06	0.06	0.06	0.06	0.05
Hybridization blank	0.05	0.06	0.06	0.06	0.06	0.06	0.05

^aValues are averages of three replications ± SDs for treatments.

^bStatistical analysis was performed for the experimental samples and values with different letters are significantly different (P < 0.05) optical densities among treatments.

^cPositive control; 4.6 × 10⁹ CFU of Mycobacterium avium subsp. paratuberculosis per extraction was used.