Table 1 Univariable analysis of animal level risk factors associated with brucellosis seropositivity

Parity

1^st Parity

52

15

28.9 (17.1, 43.1)

1.0 (reference)

0.983

2^nd Parity

17

5

29.4 (10.3, 56.0)

1.0 (0.3, 3.4)

 ≥ 3^rd Parity

15

4

26.7 (7.8, 55.1)

0.9 (0.3, 3.3)

Season the animal calved/aborted

Spring

13

3

23.1 (5.0, 53.8)

1.0 (reference)

0.363

Summer

20

3

15.0 (3.2, 37.9)

0.6 (0.1, 3.5)

Autumn

30

11

36.7 (19.9, 56.1)

1.9 (0.4, 8.6)

Winter

21

7

33.3 (14.6, 57.0)

1.7 (0.3, 8.1)

Shed code ^†

A2

16

5

31.3 (11.0, 58.7)

4.5 (0.8, 27.4)

0.002

B1

22

2

9.1 (1.1, 29.2)

1.0 (reference)

B2

21

3

14.3 (3.0, 36.3)

1.7 (0.2, 11.1)

C1

25

14

56.0 (34.9, 75.6)

12.7 (2.4, 66.6)

Animal source

Introduced

11

5

45.5 (16.7, 76.6)

2.4 (0.6, 8.7)

0.18

Self-breeding

73

19

26.0 (16.5, 37.6)

1.0 (reference)

Presence of abortion

Yes

14

11

78.6 (49.2, 95.3)

16.1 (3.9, 66.0)

 < 0.001

No

70

13

18.6 (10.3, 29.7)

1.0 (reference)