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

Table 4 Source herd betweenness centrality scores for beef and dairy replacement breeding cattle purchased in Scotland

	Number of replacement breeding cattle	Number of herds	Median source herd betweenness centrality
Beef replacement cattle
Open heifers	16 420	3229	82 521
Pregnant heifers	5795	1369	106 630
Open cows (dry)	1150	565	74 212
Open cows (calf at foot)	8458	1348	199 017
Pregnant cows (dry)	8491	1226	66 177
Pregnant cows (calf at foot)	3900	745	70 871
Dairy replacement cattle
Open heifers	2916	430	137 442
Pregnant heifers	2643	352	110 976
Open cows (dry)	707	223	111 983
Open cows (lactating)	3839	538	192 613
Pregnant cows (dry)	1276	230	109 568
Pregnant cows (lactating)	1330	217	129 386

Data from 01 July 2005 through 30 June 2006 is reported. There were a total of 4934 beef herds and 804 dairy herds that sold replacement breeding cattle. Note that some herds sold multiple types of replacement breeding cattle.

ISSN: 1297-9716