Significant reduction in bacterial shedding and improvement in milk production in dairy farms after the use of a new inactivated paratuberculosis vaccine in a field trial

Table 1 Frequency of fecal shedding at different time point as detected by IS900 PCR and isolation and rate of reduction between pre-intervention sampling and last control.

IS900-PCR		AI0		PI1		PI2		PI4
Herd		n	%	n	%	n	%	n	%	Herd shedding reduction	P	Strategy reduction	p
T&C	HER	196	7.65	195	4.62	182	2.20		-	71.1%	0.0126	60.4%	0.0039
	URI	144	9.72	176	9.09	143	4.90		-	49.6%	0.0890
	AGE	76	17.11	76	2.63	79	2.53		-	85.2%	0.0019
VAC	END	0	-	0	-	64	3.13	71	0.0	100.0%*	0.2229
	SAG	46	32.56	48	0.00	34	5.88		-	81.9%	0.0036	85.8%	<0.0001
	SAL	63	15.87	60	20.00	65	1.54		-	90.3%	0.0037
MAP isolation		AI0		PI1		PI2		PI4
Herd		n	%	n	%	n	%			Herd shedding reduction	P	Strategy reduction	P
T&C	HER	193	6.74	195	3.59	182	1.65			75.4%	0.0127	45.5%	0.0760
	URI	143	4.20	176	4.55	143	4.90			-16.7%	0.7140
	AGE	76	2.63	76	2.63	79	0.00	-	-	100.0%	0.2388
VAC	END	88	7.95	50	10.00	64	3.13	71	0.0	100.0%*	0.0142
	SAG	46	0	48	0.00	38	5.26			-	0.1981	68.2%	0.0243
	SAL	63	7.94	60	1.67	65	0.00			100.0%	0.0266

T&C: Testing and culling; VAC: Vaccination; HER, URI, AGE, END, SAG, SAL: Herd codes; AI0: Ante-intervention sampling; PI1: First post-intervention sampling; PI2: Second post-intervention sampling (includes 48 months control for farm END); PI4: Fourth post-intervention sampling (corresponds to 60 months post-intervention only for END). Reduction is calculated as the quotient of the difference in proportions to the initial proportion. * Herd reduction calculated at the last control for END. p: Fisher exact test probability of the difference being due to chance.

ISSN: 1756-0500