|
Variable
|
n
|
Coefficient
|
SE
|
p
|
CIa
| |
OR
|
CIb
| |
|---|
|
Intercept
| |
2.48
|
0.25
| | | | | | |
|
Age category
|
|
8 weeks
| |
reference
| | | | |
reference
| | |
|
14 weeks
|
16
|
-0.06
|
0.2
|
0.76
|
-0.45
|
0.33
|
reference
| | |
|
Gilts
|
16
|
0.52
|
0.2
|
0.01
|
0.12
|
0.92
|
reference
| | |
|
Parity 1
|
16
|
0.93
|
0.2
|
< 0.01
|
0.53
|
1.33
|
10.8
|
3.54
|
33.02
|
|
Parity 2
|
16
|
1.14
|
0.21
|
< 0.01
|
0.74
|
1.54
|
16.3
|
5.44
|
48.84
|
|
Parity 3
|
16
|
1.19
|
0.2
|
< 0.01
|
0.79
|
1.59
|
18.8
|
6.4
|
54.88
|
|
Parity 4
|
16
|
1.08
|
0.2
|
< 0.01
|
0.68
|
1.48
|
12.72
|
4.21
|
38.41
|
|
Parity 5+
|
16
|
1.31
|
0.2
|
< 0.01
|
0.91
|
1.71
|
8.39
|
2.87
|
24.56
|
|
Distance to nearest pig unit (miles)
|
16
|
-0.06
|
0.02
|
< 0.01
|
-0.1
|
-0.01
|
0.88
|
0.78
|
0.99
|
|
Quarantine facilities on farm
|
|
Not present
|
4
|
reference
| | | | | | | |
|
Present
|
12
|
-0.56
|
0.24
|
< 0.05
|
-1.02
|
-0.1
|
0.27
|
0.08
|
0.87
|
|
Estimation of random effects:
|
|
Variation between herds
| |
0.12
|
0.06
| | | | | | |
|
Variation between pens
| |
0.29
|
0.05
| | | | | | |
|
Variation between pigs
| |
0.24
|
0.01
| | | | | | |
- Multivariable three level mixed model of factors associated with log IRPC of 774 pigs belonging to 16 herds that had seronegative young stock.
- Sample size (n); standard error (SE); probability function (p); 95% confidence interval (CIa) when pigs' log IRPC (+12) values were used as a continuous outcome variable; Odds Ratios (OR) and 95% confidence interval (CIb) when pig-level seropositivity (absence/presence of antibodies) was used as a comparative binary outcome variable (exp(coefficient+/-(1.96 × standard error))).
