Not all cows are epidemiologically equal: quantifying the risks of bovine viral diarrhoea virus (BVDV) transmission through cattle movements

Table 5 Summary of the predicted relative risks associated with different types of beef and dairy replacement breeding cattle movements

	Empirical risk factor analysis^†	Within-herd simulation model^‡	Network characterizations*	Overall risk score
Beef replacement cattle
Open cows (calf at foot)	2.09	1.23	2.41	5.73
Pregnant heifers	2.18	1.76	1.29	5.23
Pregnant cows (calf at foot)	1.00	1.19	0.86	3.05
Open heifers	1.00	1.00	1.00	3.00
Pregnant cows (dry)	1.00	0.82	0.80	2.62
Open cows (dry)	1.00	0.16	0.90	2.06
Dairy replacement cattle
Open heifers	3.06	1.00	1.00	5.06
Open cows (lactating)	1.00	0.67	1.40	3.07
Pregnant heifers	1.00	0.92	0.81	2.73
Pregnant cows (lactating)	1.00	0.68	0.94	2.62
Pregnant cows (dry)	1.00	0.64	0.80	2.44
Open cows (dry)	1.00	0.44	0.81	2.25

^†Based on the odds ratios from the multivariable analysis. Replacement breeding cattle groups that were not significant in the multivariable analysis were assigned a score of 1.00.
^‡Based on the odds ratios directly reported in the original within-herd simulation model analysis.
*Calculated as the magnitude difference in betweenness centrality scores relative to the value for open heifers.
An overall risk score was calculated for each replacement breeding cattle group by summing the relative risks predicted by each of the study analyses.

ISSN: 1297-9716