From: Characterization of virulence genes in Escherichia coli strains isolated from pre-weaned calves in the Republic of Korea
Age (days)
E. coli
OR
P value
95% CI
1–20 (ref.)
1.00
–
21–40
2.31
< 0.001
1.62–3.28
41–60
2.15
1.42–3.25