Table 5.

Summary of results of two phenotypic studies on antimicrobial resistance of G. anatis and M. haemolytica from poultry.

Study	Reference (country)	Year of study	No. isolates	Testing method	Interpretation	Phenotypic resistance
1	(34) (United States)a	1998–1992	92	Disk diffusionb	NCCLS M31-A2 (2002)	PEN (92.4%), AMP (5.4%), CEF (0%), CN (1.1%), AK (0%), SPC (73.9%), ERY (100%), CLD (100%), TE (93.5%), SDX (85.4%), SXT (0.9%), ENR (1.3%)
2	(52) (United States)	2006–2011	84	Broth microdilution	CLSI M31-A2 (2002)	PEN (70.0% R), AMX (36.0% R; 21.0% I), CEF (3.0% R; 7.0% I), S (21.0% R; 4.0% I), NEO (14.0% R; 22.0% I), CN (4.0% R; 3.0% I), NOV (100% R), ERY (43.0% R; 57.0% I), TYL (100% R), CLD (97.0% R), SPC (0% R; 89.0% I), FFN (3.0% R; 11.0% I), TE (90.0% R; 3.0% I), OTC (83.0% R; 3.0% I), STZ (8.0% R; 10.0% I), SDX (43.0% R; 14.0% I), SXT (3.0% R; 14.0% I), ENR (4.0% R; 3.0% I)

In studies where intermediate susceptibility is given, results are presented as: R, fully resistant; I, intermediate resistant.

CLSI, Clinical Laboratory Standard Institute; NCCLS, National Committee for Clinical Laboratory Standards; AK, amikacin; AMP, ampicillin; AMX, amoxicillin; CEF, ceftiofur; CLD, clindamycin; CN, gentamicin; ENR, enrofloxacin; ERY, erythromycin; FFN, florfenicol; NEO, neomycin; NOV, novobiocin; OTC, oxytetracycline; PEN, penicillin; S, streptomycin; SDX, sulfadimethoxine; SPC, spectinomycin; STZ, sulfathiazole; SXT, co-trimoxazole; TE, tetracycline; TYL, tylosin.

^aStrains identified as M. haemolytica.

^bMIC distributions reported;.disk concentrations reported.