Table 3 Results from the univariable logistic regression analysis of variables significantly (P ≤ 0.20) associated with Escherichia coli isolates (n = 95) with or without antimicrobial resistance (from 95 healthy or diarrheic calves from 85 Swedish dairy herds).

Herd factors

Age at sampling

0: 0-11 days

24

10

1: 12-21 days

13

16

2: ≥ 22 days

19

10

0.09*

Any respiratory syndromes

0: No

50

33

1: Yes

7

1

0.10

Herd size (no of cows)

0: < 55

14

17

1: 55-120

20

13

2: ≥ 121

21

6

0.04*

Time for separation of cow and calf

0: < 24 h after calving

33

14

1: 1-3 days after calving

12

10

2: > 3 days after calving

9

12

0.09*

Usage of DHS tablets to treat diarrhea

0: Never

40

21

1: Sometimes/Often

15

15

0.20*

Presence of virulence genes

Presence of espP

0: No

11

19

1: Yes

15

3

0.002*

Presence of irp

0: No

12

19

1: Yes

14

3

0.003*

Presence of fyuA

0: No

13

18

1: Yes

13

4

0.02*