Table 2

Odds ratios (OR) from multivariate analysis of potential risk factors for farms being infected with Salmonella Cubana in the outbreak in pig farms in Sweden 2003.



OR (90% CI





Farm positive in feed and/or faeces (n = 49)
Farm positive in faeces (n = 31)

Type of production:



Integrated vs piglet

3.19 (0.29 – 35.0)
N.i.
Fattening vs piglet

38.2 (1.57 – 927.8)
N.i.
Herd size:



No. of pigs (OR per extra 100 pigs)




piglet producing
1.17 (0.90 – 1.52)
N.i.

fattening
0.84 (0.57 – 1.52)
N.i.

integrated
1.05 (0.80–1.79)
N.i.
1–5 stable units vs ≥ 11

N.i.
0.22 (0.06 – 0.75)
6–10 stable units vs ≥ 11

N.i.
0.31 (0.08 – 1.23)
Type of feed:



Other feed types vs soy

0.08 (0.01 – 0.75)
N.i.
First feed delivery week:



18 vs 22–23

N.i.
0.27 (0.04 – 1.98)
19 vs 22–23

N.i.
0.22 (0.05 – 0.89)
20 vs 22–23

N.i.
0.33 (0.07 – 1.50)
21 vs 22–23

N.i.
0.15 (0.02 – 1.15)

Reference variables (baseline) are written in italics. N.i. = not included, (not significant in the univariate analysis).

Österberg et al. Acta Veterinaria Scandinavica 2006 47:13   doi:10.1186/1751-0147-47-13