Comparison of culture, ELISA and PCR techniques for salmonella detection in faecal samples for cattle, pig and poultry

Table 5 Results from trial 7–9; cattle faecal samples artificially contaminated with salmonella. Faeces originating from one cattle farm (Trial 7) and three cattle farms (Trial 8–9). For each trial different spiking levels of salmonella were constructed (Trial 7 S. Typimurium DT1, Trial 8 S. Dublin, Trial 9 S. Tennesse), each spiking level containing six 25 g samples of faeces

CFU salm/25 g	NMKL	MSRV	MSRV PCR	SELENIT CYSTINE	VIDAS SLM	SELECTA ELISA	SELECTA CULTURE	OPTIMA ELISA	OPTIMA CULTURE	BAX^®	SELECTA PCR	SELECTA IMS PCR
TRIAL 7
0	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6
15,000	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6
1,500	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6	6/6
150	6/6	6/6	6/6	6/6	0/6	6/6	6/6	0/6	3/6	6/6	6/6	6/6
15	3/6	6/6	6/6	6/6	0/6	6/6	6/6	0/6	0/6	6/6	6/6	6/6
TRIAL 8
0	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6
400,000	2/6	N.P***	N.P***	6/6	3/6	N.P***	N.P***	N.P***	N.P***	N.P***	N.P***	N.P***
82,000	0/6	6/6	6/6	6/6	0/6	6/6	6/6	0/6	0/6	N.P***	N.P***	N.P***
9,000	0/6	6/6	6/6	2/6	0/6	6/6	6/6	0/6	0/6	6/6	6/6	6/6
900	0/6	6/6	6/6	0/6	0/6	6/6	6/6	0/6	0/6	0/6	6/6	6/6
90	0/6	6/6	6/6	0/6	0/6	1/6	4/6	0/6	0/6	0/6	6/6	6/6
9	0/6	5/6	5/6	0/6	0/6	0/6	2/6	0/6	0/6	0/6	1/6	3/6
TRIAL 9
0	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6	0/6
6,600	6/6	6/6	6/6	5/6	6/6	6/6	6/6	5/6	6/6	6/6	6/6	6/6
660	6/6	6/6	6/6	6/6	6/6	6/6	6/6	5/6	6/6	6/6	6/6	6/6
66	2/6	6/6	6/6	3/6	0/6	6/6	6/6	1/6	6/6	6/6	6/6	6/6
7	0/6	6/6	6/6	1/6	0/6	2/6	6/6	0/6	0/6	6/6	6/6	6/6
TP*	37	77	77	53	27	63	72	23	33	54	67	69
TN*	18	18	18	18	18	18	18	18	18	18	18	18
FP*	0	0	0	0	0	0	0	0	0	0	0	0
FN*	47	1	1	31	57	15	6	55	45	18	5	3
AC**	0.54	0.99	0.99	0.69	0.44	0.84	0.94	0.43	0.53	0.8	0.94	0.97
SE**	0.44	0.99	0.99	0.63	0.32	0.81	0.92	0.29	0.42	0.75	0.93	0.96
SP**	1.0	1.0	1.0	1.0	1.0	1.0	1.0	1.0	1.0	1.0	1.0	1.0

*TP = True positives, TN = True negatives, FP = False positives, FN = False negatives
**AC = Accuracy, SE = Sensitivity, SP = Specificity
***N.P = not performed

ISSN: 1746-6148