Table 2.

Total number of animal samples (S) and number of ESBL-positive samples (E) grouped by exposure to individual animal treatment 2 months prior to sampling, excluding exposure due to colostrum feeding of calves, for five selected Dutch conventional dairy cattle farms, for which detailed AMU data were available, during 2014–15

		No antimicrobial		Only first-choice antimicrobial		First- and second-choice antimicrobial
Farm	Sample	S	E	S	E	S	E
4	Group 1	40	2	0	0	0	0
	Group 2	88	1	0	0	0	0
	Group 3	80	2	1	0	0	0
	Group 4	89	2	2	0	3	1
	Total 1–4	297	7	3	0	3	1
5	Group 1	53	1	0	0	0	0
	Group 2	141	0	1	0	0	0
	Group 3	111	0	2	0	0	0
	Group 4	97	2	0	0	0	0
	Total 1–4	402	3	3	0	0	0
14	Group 1	58	0	0	0	0	0
	Group 2	119	1	0	0	0	0
	Group 3	74	0	0	0	0	0
	Group 4	207	56	1	1	0	0
	Total 1–4	458	57	1	1	0	0
15	Group 1	26	20	0	0	0	0
	Group 2	127	37	0	0	0	0
	Group 3	142	43	0	0	0	0
	Group 4	205	96	3	3	0	0
	Total 1–4	500	196	3	3	0	0
19	Group 1	41	9	0	0	0	0
	Group 2	136	16	0	0	0	0
	Group 3	140	27	0	0	0	0
	Group 4	169	46	2	1	1	1
	Total 1–4	486	98	2	1	1	1