Table 1.

Summary of Salmonella results by sample type or location of environmental swabbing and mixed-effects model outputs comparing sample results from the two farm types (Farm ID used as a random effect)

Sample type	Platinum farms			Control farms			Model result
	Positive	Negative	%pos.	Positive	Negative	% pos.	Odds Ratio	P-value
Pen floor faeces from pigs	68	3489	1.9	924	5265	14.9	0.07	<0.01
Pooled faeces samples	67	2405	2.7	786	3402	18.8	0.07	<0.01
Individual faeces samples	1	1084	0.1	138	1863	6.9	0.01	0.02
Sick Pen	1	43	2.3	20	27	42.6	0.01	0.04
Boot Dip	0	22	0.0	1	38	2.6	n/a
C&Da pen	0	68	0.0	9	77	10.5	n/a
Pig handling equipment	0	35	0.0	13	31	29.5	n/a
Walkways	10	143	6.5	71	138	34.0	0.11	<0.01
Wild bird faeces	3	19	13.6	15	37	28.8	0.55	0.34
Rodent faeces/carcases	0	41	0.0	4	61	6.2	n/a
Pet/wild mammal faeces	0	3	0.0	0	1	0.0	n/a
Other farm species	0	8	0.0	4	24	14.3	n/a
Water sources	1	31	3.1	0	59	0.0	n/a
Feed sources	1	75	1.3	7	95	6.9	0.17	0.13
Run Off/pooled water	5	74	6.3	62	89	41.1	0.04	<0.01
Waste handling	6	33	15.4	40	45	47.1	0.10	0.01
Vehicles	5	33	13.2	38	40	48.7	0.17	0.02

^aPen surfaces, feeders, drinkers and equipment sampled after cleaning and disinfection (C&D). n/a model could not successfully converge, unstable model or no result possible due to lack of positive values.