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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