TABLE 4.

Antimicrobial susceptibilities to single compounds of Edwardsiella isolates analyzed in the current study^a

Antibiotic (range, mg/liter)	Taxon	No. of strains with MIC (mg/liter):
		≤0.5	1	2	4	8	16	32	64	128	≥256
Aminoglycosides
Amikacin (8–32)	All strains				47
Gentamicin (0.5–8)	E. anguillarum	5	1
	E. hoshinae		1
	E. ictaluri	2	1
	E. piscicida	23	2
	E. tarda	5	6
Neomycin (2–32)	All strains		47
Spectinomycin (8–64)	E. anguillarum				7
	E. hoshinae				1
	E. ictaluri				1		1	1
	E. piscicida				22		3
	E. tarda				8		2		1
Streptomycin (8–1,024)	All strains				45			1			1
Tobramycin (2–8)	All strains		47
Carbapenems
Doripenem (0.5–4)	All strains	47
Ertapenem (0.25–8)	All strains	47
Imipenem (0.5–8)	All strains	47
Meropenem (0.5–8)	All strains	47
Cephalosporins
Cefepime (4–32)	All strains			47
Cefazolin (1–16)	E. anguillarum	4		3
	E. hoshinae	1
	E. ictaluri	3
	E. piscicida	13		10	2
	E. tarda	9		2
Ceftazidime (1–16)	All strains	46		1
Ceftiofur (0.25–4)	All strains	47
Ceftriaxone (0.5–32)	All strains	47
Macrolides
Erythromycin (0.12–4)	E. anguillarum			1		6
	E. hoshinae			1
	E. ictaluri					3
	E. piscicida			1		24
	E. tarda			1		10
Tylosin tartrate (2.5–20)	All strains					1	1	45
Penicillins
Amoxicillin (0.25–16)	E. anguillarum	1	6
	E. hoshinae	1
	E. ictaluri	3
	E. piscicida	1	9	11	4
	E. tarda	10	1
Ampicillin (8–16)	All strains				47
Penicillin (0.06–8)	E. anguillarum			1	3	2	1
	E. hoshinae	1
	E. ictaluri	2		1
	E. piscicida				4	10	11
	E. tarda			6	3	2
Piperacillin (16–32)	All strains					46				1
Quinolones
Ciprofloxacin (0.5–2)	All strains	46	1
Enrofloxacin (0.12–2)	All strains	46	1
Levofloxacin (1–8)	All strains	47
Tetracyclines
Minocycline (1–8)	E. anguillarum	1			3	3
	E. hoshinae	1
	E. ictaluri	3
	E. piscicida	5		10	6	1	3
	E. tarda	11
Oxytetracycline (0.25–8)	E. anguillarum	2	4	1
	E. hoshinae			1
	E. ictaluri	3
	E. piscicida	10	8	2		1	4
	E. tarda	2	6	1			2
Tetracycline (0.25–8)	E. anguillarum	2	5
	E. hoshinae	1
	E. ictaluri	2	1
	E. piscicida	18	2	1			4
	E. tarda	6	3				2
Other
Aztreonam (1–16)	All strains	46						1
Clindamycin (0.5–4)	E. anguillarum	1				6
	E. hoshinae			1
	E. ictaluri					3
	E. piscicida	1			5	19
	E. tarda				7	4
Florfenicol (1–8)	All strains	47
Nitrofurantoin (32–64)	All strains						46			1
Novobiocin (0.5–4)	E. anguillarum	2				5
	E. hoshinae					1
	E. ictaluri			1		2
	E. piscicida			1	5	19
	E. tarda	3	3	1	1	3
Sulfadimethoxine (32–256)	E. anguillarum										7
	E. hoshinae										1
	E. ictaluri										3
	E. piscicida										25
	E. tarda						4		1		6
Sulfathiazole (32–256)	E. anguillarum										7
	E. hoshinae										1
	E. ictaluri										3
	E. piscicida										25
	E. tarda								1	1	6
Tigecycline (1–8)	E. anguillarum	6		1
	E. hoshinae	1
	E. ictaluri	3
	E. piscicida	22		3
	E. tarda	11

^aAntimicrobial susceptibilities were determined by the broth microdilution method using the Sensititre GN4F and Avian1F plates, according to the manufacturer's protocol. Numbers in the lowest concentration of the antibiotic represent the maximal MIC at this concentration. An MIC higher than the highest concentration tested is cited in the subsequent higher concentration step.