Table 1 Association between milking process infrastructure components/variables and bulk tank total bacterial score (TBS)

Number of milking cows

67-293

24

9.89 (20)

0.045

0.0642

51-66

23

9.92 (20)

0.044

37-50

28

9.85 (19)

0.041

12-36

25

10.00 (22)

0.043

Automatic cluster removers

Yes

5

9.76 (17)

0.093

0.0924

No

95

9.92 (20)

0.022

Heated water in parlour

Yes

40

9.82 (18)

0.035

0.0002

No

60

9.99 (22)

0.028

Frequency of liner change

≤ once a year

64

9.95 (21)

0.027

0.0178

> once a year

36

9.84 (19)

0.036

Filter used

Sock filter

71

9.90 (20)

0.026

0.4361

Solid filter

10

9.89 (20)

0.069

No filter

19

9.97 (21)

0.049