Characterization of Salmonella spp. isolated from chickens in Central China

BMC Veterinary Research

Table 2 No. of isolates in different MICs and antimicrobial resistance of Salmonella isolates (n = 84)

No. of isolates in different MICs & resistance rates
Serotypes	Ampicillin				Cefotaxime				Meropenem				Gentamicin				Tetracycline
Serotypes	≤8	16	≥32		≤1	2	≥4		≤1	2	≥4		≤4	8	≥16		≤4	8	≥16
SE^a(14)	0	0	14	100.0	14	0	0	0.0	8	1	5	35.7	14	0	0	0.0	0	1	13	92.9
ST^b(11)	0	0	11	100.0	11	0	0	0.0	5	5	1	9.1	11	0	0	0.0	6	2	3	27.3
SG^c(16)	2	0	14	87.5	7	5	4	25.0	16	0	0	0.0	13	3	0	0.0	2	1	13	81.3
SGP^d(38)	0	0	38	100.0	33	3	2	5.3	34	4	0	0.0	35	2	1	2.6	22	0	16	42.1
OT^e(5)	0	0	5	100.0	4	1	0	0.0	3	2	0	0.0	5	0	0	0.0	1	0	4	80.0
Total(84)			82	97.6			6	7.1			6	7.1			1	1.2			49	58.3
No of isolates in different MICs & resistance rates
Subspecies	Tigecycline				Chloramphenicol				Ciprofloxacin				Trimethoprim-sulfamethoxazole				Colistin
Subspecies	≤2	4	≥8		≤8	16	≥32		≤1	2	≥4		≤2/38	–	≥4/76		≤2	4	≥8
SE^a(14)	14	0	0	0.0	8	1	5	35.7	8	2	4	28.6	7	0	7	50.0	2	3	9	64.3
ST^b(11)	9	2	0	0.0	6	1	4	36.4	10	0	1	9.1	7	0	4	36.4	4	4	3	27.3
SG^c(16)	13	2	1	6.3	7	0	9	56.3	16	0	0	0.0	14	0	2	12.5	5	6	5	31.3
SGP^d(38)	33	2	3	7.9	27	2	9	23.7	35	3	0	0.0	32	0	6	15.8	5	10	23	60.5
OT^e(5)	5	0	0	0.0	3	0	2	40.0	4	1	0	0.0	4	0	1	20.0	2	0	3	60.0
Total(84)			4	4.8			29	34.5			5	6.0			20	23.8			43	51.2

^aS. Enteritidis; ^bS. Typhimurium; ^cS. Gallinarum; ^dS. Pullorum; ^eother serotypes;
Escherichia coli ATCC 25922 was the quality control, the detailed results are as follows, ampicillin (8 μg/ml), cefotaxime (0.12 μg/ml), meropenem (< 0.125 μg/ml), gentamicin (1 μg/ml), tetracycline (1 μg/ml), tigecycline (0.25 μg/ml), chloramphenicol (4 μg/ml), ciprofloxacin (0.015 μg/ml), trimethoprim-sulfamethoxazole (0.5/9.5 μg/ml) and colistin (2 μg/ml)