Table 5.

Multivariable logistic regression analysis of the strength of association between potential risk factors and occurrence of AMR to ten antimicrobials among six bacteria species isolated from bovine mastitis.

Antimicrobials	Predictor Variable/Reference	B	S.E.	Wald	df	Sig.	Exp (B)	95% CI Lower EXP (B)	95% CI Upper EXP (B)
Ampicillin	Ecoli/Sube	−3.613	0.87	17.266	1	0.000	0.027	0.005	0.148
Penicillin	Sdys/Sube	−4.314	0.899	23.001	1	0.000	0.013	0.002	0.078
Erythromycin	Clinical/Subclinical	−1.544	0.779	3.931	1	0.047	0.213	0.046	0.983
Erythromycin	EC/Sube	2.808	1.154	5.921	1	0.015	16.57	1.726	159.039
Erythromycin	SA/Sube	−6.188	1.196	26.786	1	0.000	0.002	0	0.021
Erythromycin	Sdys/Sube	−4.343	0.904	23.067	1	0.000	0.013	0.002	0.076
Oxacillin	Sdys/Sube	−2.04	0.581	12.312	1	0.000	0.13	0.042	0.406
Pirlimycin	Sdys/Sube	−5.644	1.346	17.574	1	0.000	0.004	0	0.05
PEN/NOVO	Clinical/Subclinical	−1.418	0.695	4.162	1	0.041	0.242	0.062	0.946
PEN/NOVO	Sdys/Sube	−3.92	0.917	18.272	1	0.000	0.02	0.003	0.12
Tetracycline	EC/Sube	−1.376	0.55	6.253	1	0.012	0.253	0.086	0.743
Tetracycline	Kpne/Sube	−1.873	0.738	6.437	1	0.011	0.154	0.036	0.653
Tetracycline	Sdys/Sube	1.698	0.84	4.092	1	0.043	5.464	1.054	28.321
Ceftiofur	EC/Sube	−3.989	1.094	13.305	1	0.000	0.019	0.002	0.158

PEN/NOVO: Penicillin/novobiocin, Ecoli: E. coli, SA: Staphylococcus aureus, Sube: Streptococcus uberis, Sdys: Streptococcus dysgalactiae, Koxy: Klebsiella oxytoca, Kpne: Klebsiella pneumoniae, S.E: Standard error, df: degree of freedom; B: is logarism value, Exp (B): the anti-log of B, which is the logistic regression equation’s values for predicting the dependent variable, from the independent variable. 95% Wald CI for Exp (B): the 95% confidence interval of B.