Table 2 Increase in frequencies of early calving, expressed as odds-ratios (OR) for cows in herds reported as cases of Bluetongue virus serotype 8 during the 2007 outbreak and cows in herds located in the 2007 outbreak area but not reported as cases

(207–216)

1.06

0.94–1.21

0.34

1.10

0.97–1.26

0.14

(216–225)

1.18

1.05–1.33

0.01

1.20

1.06–1.35

0.004

(225–234)

1.25

1.11–1.40

<0.001

1.25

1.11–1.40

<0.001

(234–243)

1.37

1.23–1.52

<0.001

1.37

1.23–1.53

<0.001

(243–252)

1.51

1.36–1.66

<0.001

1.51

1.36–1.67

<0.001

(252–261)

1.73

1.57–1.90

<0.001

1.70

1.54–1.88

<0.001

(261–270)

1.81

1.65–1.98

<0.001

1.74

1.58–1.92

<0.001

(270–278)

2.09

1.91–2.29

<0.001

1.97

1.79–2.16

<0.001

(207–216)

1.18

1.05–1.33

<0.001

1.30

1.15–1.46

<0.001

(216–225)

1.27

1.14–1.42

<0.001

1.45

1.30–1.62

<0.001

(225–234)

1.25

1.12–1.38

<0.001

1.43

1.28–1.60

<0.001

(234–243)

1.30

1.18–1.44

<0.001

1.49

1.35–1.66

<0.001

(243–252)

1.25

1.14–1.38

<0.001

1.39

1.25–1.53

<0.001

(252–261)

1.23

1.12–1.35

<0.001

1.31

1.19–1.45

<0.001

(261–270)

1.42

1.30–1.56

<0.001

1.47

1.34–1.61

<0.001

(270–278)

1.34

1.22–1.47

<0.001

1.40

1.27–1.54

<0.001