Table 5 Multivariable logistic regression analysis of the association of cow-level mastitis with different risk factors

≤10 cows

Ref

>10 cows

3.1

1.0

3.74

<0.001

1.7 – 5.7

Local

Ref

Cross

16.4

8.3

5.55

<0.001

6.1 – 44.1

Yes

Ref

No

2.0

0.6

2.53

0.011

1.2 – 3.5

Yes

Ref

No

2.8

0.9

3.24

0.001

1.5 – 5.3

1

Ref

2

1.2

0.5

0.48

0.629

0.5 – 2.9

3

3.2

1.5

2.46

0.014

1.3 – 8.1

≥4

24.8

12.2

6.50

<0.001

9.4 – 65.2

Early (1 – 2 months)

Ref

Mid (3 – 6 months)

0.3

0.1

−4.17

<0.001

0.1 – 0.5

Late (≥7 months)

0.7

0.2

−0.99

0.323

0.4 – 1.4

Slightly dirty

Ref

Moderately dirty

2.6

0.8

3.27

0.001

1.5 – 4.7

Very dirty

8.7

4.0

4.73

<0.001

3.5 – 21.3

Pointed

Ref

Round

3.2

1.0

3.72

<0.001

1.7 – 5.9

Flat

7.6

2.8

5.57

<0.001

3.7 – 15.7

Constant

−7.44

<0.001