Table 3.

Scenarios in which stochastic modeling of bovine tuberculosis outbreaks predicted that infected herds would be falsely declared clear of M bovis after whole-herd testing initiated by detection through slaughterhouse surveillance. The model was run for a 10-year period for each of 1,000 herds.

Replacement rate (1/y)	Testing interval (mo)	No. of tests*	No. of herds
			Small herds		Medium herds		Large herds
			Cleared	Falsely cleared	Cleared	Falsely cleared	Cleared	Falsely cleared
0.33	2	1	724	1	701	7	724	3
	2	2	714	1	717	3	713	0
	2	3	722	1	718	3	723	0
	3	1	681	0	739	3	724	1
	4	2	730	0	716	1	694	0
	6	1	707	0	727	1	720	0
	8	1	709	0	721	1	708	0
	10	1	700	0	724	0	714	1
	11	1	694	1	717	0	721	0
	12	1	709	0	708	1	715	0
	14	1	712	0	725	1	695	0
	16	1	716	0	703	1	719	0
	17	1	731	0	717	0	720	1
	18	1	723	0	717	0	704	1
	22	1	716	0	728	0	720	1
0.17	2	1	806	6	804	8	818	9
	2	2	824	1	810	1	791	2
	3	1	836	1	810	2	822	0
	3	2	825	0	829	0	812	2
	4	1	811	0	809	0	796	3
	5	1	806	0	816	1	815	1
	6	1	812	0	819	0	828	0
	7	1	780	0	810	0	816	0
	9	1	804	0	810	1	828	0
	11	1	805	0	814	1	787	0
	15	1	807	0	816	0	804	1
	16	1	809	0	821	0	806	1
	20	1	807	0	825	1	793	0
	21	1	790	1	805	0	808	0
	22	1	811	0	812	0	820	2

Data are presented as the number of herds/1,000 in which M bovis infection was detected and subsequently cleared (in total) or falsely cleared.

^*Indicates number of consecutive negative whole-herd tests required for a herd to be declared free of M bovis infection. See Table 1 for remainder of key.