Table 3.

Farm B: Month of sampling, numbers of animals sampled, animal code, number of lactations, age of animal, E. coli serogroup isolated, shedding status, and virulence characteristics.

Month of Sampling	No. Lactating animals sampled	Animal code	No. of lactations	Age of animal	E. coli serogroup isolated	Shedding status CFU/swab	Virulence status of recovered isolates
							stx1	stx2	eae	hlyA
September, 2013	39	No STEC detected
December, 2013	37	VFSL868	2	3y6m	O26	100	–	+	+	–
		VFSL858	2	3y6m	O26	<10	–	+	+	–
		VFSL832∗	2	3y8m	O26	10,000	+	+	+	–
February, 2014	37	No STEC detected
April, 2014	37	VFSL578	6	7y8m	O157	<10	–	+	+	–
		VFSL700∗	4	5y8m	O157	<10	–	+	–	–
		VFSL700∗	4	5y8m	O26	10,000	+	+	+	+
		VFSL777	3	4y8m	O157	<10	–	+	+	–
		VFSL783	3	4y7m	O157	<10	–	+	+	–
		VFSL770	3	4y8m	O157	<10	–	–	+	+
May, 2014	37	VFSL724	4	5y7m	O157	<10	–	+	+	–
		VFSL780	3	4y7m	O26	100	+	+	+	–
		VFSL832∗	2	4y1m	O26	<10	+	+	+	–
		VFSL840	2	3y7m	O26	<10	–	+	+	–
June, 2014	37	VFSL763	3	4y8m	O26	<10	+	+	+	–
		VFSL788	3	4y7m	O26	<10	–	+	+	–
		VFSL646	5	6y8m	O157	10	–	+	+	–
		VFSL633	5	6y8m	O157	10,000	–	+	–	–

^∗animals positive for STEC more than once during the 1-year sampling program.