Table 3.

Determinants of resistance to the common antimicrobials including specimen source and study period among Enterococcus spp. isolates using multivariable logistic regression models, in canine clinical infections at the Cornell University Animal Health Diagnostic Center (AHDC), 2007–2020.

	Enterococcus spp.				Enterococcus faecalis				Enterococcus faecium
	Modela				Modela				Modela
	Adj. OR	95% CI	p-value	Adj. p-valuec	Adj. OR	95% CI	p-value	Adj. p-valuec	Adj. OR	95% CI	p-value	Adj. p-valuec
Resistance to ampicillin
Urinary tractb
Intestinal	3.51	2.58–4.77	<0.001	<0.001	0.76	0.04–4.10	0.792	0.859	0.76	0.45–1.28	0.291	0.458
Invasive	1.98	1.40–2.77	<0.001	0.001	0.93	0.05–4.97	0.944	0.987	0.57	0.34–0.98	0.042	0.114
Unspecified site	0.32	0.14–0.62	0.002	0.009	28*10−6	0–24*1020	0.988	0.994	0.45	0.15–1.41	0.159	0.321
Reproductive system	0.30	0.17–0.49	<0.001	<0.001	0.39	0.02–2.10	0.379	0.519	0.18	0.08–0.41	<0.001	<0.001
Skin and soft tissues	0.25	0.19–0.34	<0.001	<0.001	0.32	0.09–0.98	0.058	0.141	0.31	0.19–0.52	<0.001	<0.001
Isolation date (2007–2010)b
Isolation date (2011–2014)	0.33	0.23–0.48	<0.001	<0.001	0.49	0.06–2.95	0.431	0.571	0.31	0.18–0.53	<0.001	<0.001
Isolation date (2015–2017)	0.72	0.53–0.99	0.044	0.115	1.29	0.31–6.32	0.733	0.813	1.30	0.76–2.22	0.335	0.494
Isolation date (2018–2020)	1.42	1.07–1.90	0.015	0.052	1.91	0.52–9.00	0.354	0.503	2.18	1.34–3.54	0.002	0.007
Resistance to penicillin G
Urinary tractb
Intestinal	0.88	0.55–1.43	0.616	0.735	0.32	0.01–8.35	0.428	0.570	0.70	0.31–1.50	0.369	0.513
Invasive	0.78	0.49–1.27	0.319	0.485	0.33	0.01–8.62	0.443	0.580	0.87	0.39–1.84	0.717	0.809
Unspecified site	0.16	0.08–0.30	<0.001	<0.001	10−6	0–48*1021	0.987	0.994	0.50	0.16–1.65	0.246	0.411
Reproductive system	0.10	0.05–0.18	<0.001	<0.001	0.32	0.03–7.05	0.360	0.508	0.22	0.08–0.54	0.001	0.006
Skin and soft tissues	0.10	0.07–0.16	<0.001	<0.001	0.35	0.06–6.47	0.321	0.485	0.51	0.24–1.06	0.079	0.182
Isolation date (2007–2010)b
Isolation date (2011–2014)	0.72	0.48–1.08	0.114	0.246	1.48	0.28–10.7	0.655	0.763	0.83	0.45–1.49	0.525	0.650
Isolation date (2015–2017)	1.32	0.90–1.93	0.154	0.314	1.77	0.38–12.5	0.499	0.626	2.17	1.19–4.02	0.012	0.044
Isolation date (2018–2020)	1.62	1.13–2.33	0.009	0.033	1.61	0.34–11.4	0.576	0.700	2.86	1.57–5.26	<0.001	0.004
Resistance to tetracycline
Urinary tractb
Intestinal	0.10	0.03–0.25	<0.001	<0.001	0.13	0.02–0.43	0.005	0.020	0.06	0.01–0.20	<0.001	0.001
Invasive	0.34	0.19–0.58	<0.001	0.001	0.29	0.12–0.65	0.004	0.018	0.35	0.13–0.89	0.030	0.088
Unspecified site	0.39	0.20–0.74	0.005	0.021	0.43	0.19–0.89	0.031	0.089	0.21	0.03–1.19	0.088	0.201
Reproductive system	0.28	0.16–0.47	<0.001	<0.001	0.32	0.15–0.61	0.001	0.006	0.69	0.13–3.99	0.656	0.763
Skin and soft tissues	0.19	0.13–0.26	<0.001	<0.001	0.18	0.12–0.27	<0.001	<0.001	0.60	0.26–1.41	0.242	0.411
Isolation date (2007–2010)b
Isolation date (2011–2014)	0.60	0.44–0.81	<0.001	0.004	0.58	0.40–0.83	0.003	0.013	0.95	0.44–2.03	0.886	0.945
Isolation date (2015–2017)	0.50	0.37–0.66	<0.001	<0.001	0.58	0.41–0.82	0.002	0.009	0.64	0.30–1.37	0.251	0.415
Isolation date (2018–2020)	0.33	0.25–0.44	<0.001	<0.001	0.37	0.26–0.52	<0.001	<0.001	0.19	0.10–0.36	<0.001	<0.001
Resistance to doxycycline
Urinary tractb
Intestinal	0.38	0.18–0.77	0.008	0.031	0.54	0.17–1.76	0.296	0.461	0.28	0.09–0.86	0.030	0.088
Invasive	0.99	0.52–1.82	0.968	0.994	1.11	0.39–3.38	0.847	0.908	0.76	0.30–1.86	0.549	0.672
Unspecified site	0.62	0.30–1.18	0.167	0.330	0.85	0.30–2.57	0.767	0.841	0.52	0.13–2.07	0.352	0.503
Reproductive system	0.51	0.27–0.93	0.032	0.091	0.98	0.36–2.84	0.976	0.994	0.30	0.09–0.92	0.039	0.108
Skin and soft tissues	0.44	0.25–0.76	0.003	0.013	0.70	0.28–1.92	0.470	0.602	0.41	0.16–0.98	0.049	0.124
Isolation date (2007–2010)b
Isolation date (2011–2014)	0.79	0.55–1.15	0.215	0.397	1.09	0.67–1.82	0.725	0.809	0.64	0.30–1.32	0.229	0.403
Isolation date (2015–2017)	0.77	0.53–1.12	0.171	0.331	1.03	0.63–1.73	0.906	0.956	0.62	0.28–1.34	0.229	0.403
Isolation date (2018–2020)	0.01	0.00–0.03	<0.001	<0.001	21*10−7	NDd	0.962	0.994	0.02	0–0.07	<0.001	<0.001
Resistance to erythromycin
Urinary tractb
Intestinal	1.38	0.76–2.43	0.274	0.440	1.46	0.65–3.23	0.353	0.503	0.72	0.09–4.01	0.722	0.809
Invasive	0.83	0.47–1.42	0.498	0.626	1.99	0.88–4.45	0.095	0.216	0.25	0.04–0.95	0.076	0.178
Unspecified site	0.73	0.40–1.32	0.305	0.469	2.22	0.99–4.93	0.049	0.124	0.29	0.03–2.66	0.243	0.411
Reproductive system	0.55	0.32–0.92	0.027	0.080	2.09	0.98–4.38	0.053	0.131	0.14	0.02–0.60	0.017	0.056
Skin and soft tissues	0.74	0.44–1.18	0.220	0.403	2.30	1.13–4.58	0.018	0.061	0.39	0.06–1.51	0.229	0.403
Isolation date (2007–2010)b
Isolation date (2011–2014)	0.87	0.65–1.16	0.347	0.503	1.00	0.69–1.43	0.994	0.994	0.84	0.38–1.80	0.649	0.763
Isolation date (2015–2017)	0.79	0.59–1.05	0.110	0.239	0.66	0.46–0.93	0.019	0.061	3.37	1.27–10.1	0.020	0.063
Isolation date (2018–2020)	0.75	0.56–0.99	0.043	0.114	0.53	0.38–0.75	<0.001	0.002	4.28	1.58–13.1	0.006	0.023
Resistance to chloramphenicol
Urinary tractb
Intestinal	1.91	0.81–5.29	0.169	0.330	1.22	0.34–5.80	0.776	0.847	2.11	0.66–0.39	0.254	0.417
Invasive	1.63	0.68–4.55	0.303	0.469	0.23	0.03–1.47	0.119	0.253	3.55	1.13–15.8	0.052	0.129
Unspecified site	1.88	0.74–5.40	0.207	0.386	1.50	0.45–6.85	0.550	0.672	2.85	0.48–17.0	0.232	0.404
Reproductive system	1.16	0.48–3.24	0.756	0.835	0.96	0.29–4.31	0.946	0.987	1.02	0.13–6.55	0.981	0.994
Skin and soft tissues	1.00	0.46–2.64	0.994	0.994	0.72	0.25–3.08	0.601	0.721	1.92	0.59–8.64	0.323	0.485
Isolation date (2007–2010)b
Isolation date (2011–2014)	0.82	0.50–1.37	0.449	0.583	0.75	0.41–1.38	0.352	0.503	1.07	0.36–3.20	0.904	0.956
Isolation date (2015–2017)	1.47	0.94–2.36	0.099	0.221	1.13	0.65–2.00	0.680	0.786	2.71	1.12–7.34	0.035	0.098
Isolation date (2018–2020)	0.81	0.49–1.33	0.387	0.523	0.57	0.31–1.06	0.075	0.178	1.60	0.64–4.40	0.331	0.492
Resistance to enrofloxacin
Urinary tractb
Intestinal	2.70	1.84–4.06	<0.001	<0.001	1.45	0.92–2.37	0.121	0.253	1.71	0.44–11.3	0.494	0.626
Invasive	1.77	1.29–2.47	<0.001	0.003	1.20	0.78–1.88	0.421	0.565	1.48	0.65–3.70	0.375	0.518
Unspecified site	1.60	1.09–2.42	0.021	0.065	1.64	1.07–2.58	0.027	0.080	1.49	0.26–28.2	0.712	0.809
Reproductive system	0.86	0.66–1.13	0.275	0.440	1.14	0.82–1.59	0.444	0.580	0.21	0.09–0.53	<0.001	0.004
Skin and soft tissues	1.13	0.95–1.34	0.164	0.329	1.22	1.01–1.49	0.044	0.115	1.76	0.72–4.96	0.244	0.411
Isolation date (2007–2010)b
Isolation date (2011–2014)	1.18	0.95–1.46	0.135	0.279	1.26	0.98–1.61	0.071	0.171	1.33	0.70–2.56	0.385	0.523
Isolation date (2015–2017)	1.90	1.51–2.38	<0.001	<0.001	1.86	1.43–2.41	<0.001	<0.001	11.3	3.71–49.7	<0.001	0.001
Isolation date (2018–2020)	1.43	1.15–1.77	0.001	0.007	1.23	0.96–1.59	0.103	0.227	45.3	8.94–829	<0.001	0.002
Resistance to rifampin
Urinary tractb
Intestinal	1.33	0.78–2.27	0.290	0.458	0.83	0.31–2.03	0.688	0.786	1.18	0.51–2.67	0.688	0.786
Invasive	0.95	0.56–1.57	0.831	0.896	0.59	0.23–1.40	0.246	0.411	1.30	0.58–2.84	0.520	0.649
Unspecified site	0.70	0.40–1.21	0.204	0.385	0.58	0.22–1.36	0.227	0.403	0.46	0.14–1.54	0.197	0.379
Reproductive system	0.68	0.41–1.10	0.121	0.253	0.81	0.32–1.85	0.633	0.751	0.34	0.13–0.86	0.024	0.075
Skin and soft tissues	0.85	0.53–1.32	0.468	0.602	0.69	0.29–1.48	0.366	0.513	0.65	0.30–1.36	0.266	0.432
Isolation date (2007–2010)b
Isolation date (2011–2014)	1.18	0.91–1.53	0.203	0.385	1.55	1.12–2.13	0.008	0.030	0.85	0.46–1.55	0.595	0.718
Isolation date (2015–2017)	1.73	1.33–2.26	<0.001	<0.001	2.11	1.51–2.96	<0.001	<0.001	3.49	1.80–6.96	<0.001	0.002
Isolation date (2018–2020)	1.89	1.46–2.46	<0.001	<0.001	1.88	1.36–2.59	<0.001	0.001	2.95	1.57–5.60	<0.001	0.004

^aOrigin of clinical sample and date of isolation (divided into four periods: 2007–2010, 2011–2014, 2015–2017, and 2018–2020) were entered in the model.

^bReference group.

^cp-values were adjusted according to Benjamini and Hochberg (1995).

^dND: We are not able to determine the exact 95% confidence interval.

Bold values are significant results (p<0.05 after Benjamini and Hochberg adjustment).