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Table 1 Linear mixed regression models for quarter somatic cell count and shedding of S. chromogenes IM.

From: Colonization and local host response following intramammary Staphylococcus chromogenes challenge in dry cows

Outcome variable

Predictor variable

Dry period

Early lactation

βa

SEb

LSMc

P

β

SE

LSM

P

Ln qSCC (cells/µL)

Quarter inoculation status

   

   

0.09d

 

 Non-inoculated

Ref.f

4.28

 

 Inoculated and non-colonized

1.13

0.58

5.41

NSe

 

 Inoculated and colonized

1.77

0.59

6.05

0.05

 

Time of samplingi

   

   

 <0.01d

 

 D-1

Ref.

4.14

 

 C

2.33

0.21

6.47

 <0.01

 

 L1

2.02

0.23

6.16

 <0.01

 

 L2

1.72

0.25

5.85

 <0.01

 

 L3

0.99

0.24

5.13

 <0.01

 

 L4

0.51

0.24

4.65

0.03

 

 L5

0.65

0.23

4.79

 <0.01

 

 L6

0.65

0.21

4.78

 <0.01

 

Inoculation status × Time of samplingg

 <0.01d

Log (CFU/mL + 1)

Quarter inoculation dose (CFU)

   

0.08d

   

0.03d

 

 0

Ref.

0.00

Ref.

0.00

 

 100

1.18

1.15

1.18

NS

0.69

1.26

0.69

NS

 

 100 000

0.92

1.10

0.92

NS

0.37

1.20

0.37

NS

 

 10 000 000

3.27

1.21

3.27

0.05

2.87

1.25

2.87

0.09

 

Time of sampling

   

 <0.01d

   

 

 D-1

Ref.

0.00

 

 D14

1.76

0.34

1.76

 <0.01

 

 D27

1.83

0.38

1.82

 <0.01

 

 D41

1.81

0.38

1.80

 <0.01

 

Time of sampling

   

   

NSd

 

 C

Ref.

1.10

 

 L1

−0.09

0.16

1.01

NS

 

 L2

−0.10

0.21

1.00

NS

 

 L3

−0.09

0.24

1.00

NS

 

 L4

−0.15

0.26

0.94

NS

 

 L5

−0.29

0.27

0.81

NS

 

 L6

−0.10

0.27

1.00

NS

 

Inoculation dose × Time of samplingh

0.03d

NSd

  1. Linear mixed regression models for the natural log of the quarter milk somatic cell count (Ln qSCC) and shedding of log10 transformed bacterial count of S. chromogenes IM [Log (CFU/mL + 1)] in both the dry period (shedding) and in early lactation (qSCC and shedding)
  2. aRegression coefficient of difference of LSM
  3. bStandard error
  4. cLeast square means
  5. dP value for overall effect
  6. eNot significant
  7. fReference
  8. gInteraction term visualized in Figure 3 based on the least square means
  9. hInteraction term visualized in Figure 2 based on the least square means
  10. iOverview of the experimental set-up and days of sampling is visualized in Figure 1