Table 4 The estimated coefficients (β) and 95% confidence interval (CI) for associations between ln-transformed somatic cell count (lnSCC), sampling period, parity, milk yield and year. Based on 1901 samples from 384 Norwegian dairy goats in four herds, all of which were culture-negative at the time of sampling. Goat nested within herd was included as random effect

 (Intercept)

5.74

5.51–5.98

< 0.001

Sampling period^a

 Indoor spring/early lactation

Reference

 Pasture/mid lactation

0.85

0.65–1.05

< 0.001

 Fall/late lactation

0.97

0.76–1.19

< 0.001

Parity

 First

Reference

 Second

0.66

0.43–0.89

< 0.001

 Third

1.23

0.93–1.53

< 0.001

 ≥Fourth

1.07

0.83–1.30

< 0.001

Milk yield^b

-0.38

-0.46 – -0.31

< 0.001

Year

 2021

Reference

 2022

-0.43

-0.52 – -0.34

< 0.001

Interaction terms

 Period [Pasture] * Parity [Second]

0.58

0.29–0.88

< 0.001

 Period [Fall] * Parity [Second]

-0.03

-0.34–0.28

0.839

 Period [Pasture] * Parity [Third]

0.60

0.24–0.95

0.001

 Period [Fall] * Parity [Third]

0.39

0.02–0.77

0.040

 Period [Pasture] * Parity [≥ Fourth]

0.90

0.66–1.15

< 0.001

 Period [Fall] * Parity [≥ Fourth]

0.31

0.05–0.57

0.021