Table 3 The estimated coefficients (β) and 95% confidence interval (CI) for associations between ln-transformed somatic cell count (lnSCC), intramammary infection status^a and non-infectious factors (fixed effects). Based on 3125 samples from 451 Norwegian dairy goats in four herds. Goat nested within herd was included as random effect

 (Intercept)

5.38

5.20–5.56

< 0.001

IMI-status^a

 Negative

Reference

 Staphylococcus aureus

1.60

1.22–1.97

< 0.001

 Staphylococcus epidermidis

0.90

0.46–1.34

< 0.001

 Staphylococcus caprae

0.41

0.08–0.73

0.015

 Staphylococcus warneri

0.50

0.23–0.78

< 0.001

 Other

0.10

-0.16–0.36

0.438

Sampling period^b

 Indoor spring/early lactation

Reference

 Pasture/mid lactation

1.29

1.21–1.37

< 0.001

 Fall/late lactation

1.10

1.02–1.19

< 0.001

Parity

 First

Reference

 Second

0.78

0.63–0.93

< 0.001

 Third

1.53

1.34–1.72

< 0.001

 ≥Fourth

1.39

1.23–1.55

< 0.001

Milk yield^c

-0.30

-0.36 – -0.25

< 0.001

Year

 2021

Reference

 2022

-0.34

-0.42 – -0.27

< 0.001

Interaction terms

 IMI [S.aureus] * Parity [Second]

-0.33

-0.79–0.14

0.171

 IMI [S.epidermidis] * Parity [Second]

-0.56

-1.09 – -0.04

0.036

 IMI [S.caprae] * Parity [Second]

0.03

-0.36–0.43

0.868

 IMI [S.warneri] * Parity [Second]

-0.11

-0.50–0.28

0.595

 IMI [Other] * Parity [Second]

0.54

0.19–0.88

0.002

 IMI [S.aureus] * Parity [Third]

-0.25

-0.82–0.32

0.387

 IMI [S.epidermidis] * Parity [Third]

-0.80

-1.54 – -0.06

0.034

 IMI [S.caprae] * Parity [Third]

-0.49

-0.99–0.02

0.059

 IMI [S.warneri] * Parity [Third]

-0.55

-1.01 – -0.10

0.016

 IMI [Other] * Parity [Third]

-0.23

-0.63–0.17

0.256

 IMI [S.aureus] * Parity [≥ Fourth]

-0.58

-1.03 – -0.13

0.011

 IMI [S.epidermidis] * Parity [> third]

-0.76

-1.29 – -0.24

0.005

 IMI [S.caprae] * Parity [≥ Fourth]

-0.31

-0.70–0.08

0.124

 IMI [S.warneri] * Parity [≥ Fourth]

-0.54

-0.90 – -0.19

0.003

 IMI [Other] * Parity [≥ Fourth]

0.08

-0.23–0.38

0.622