An Effort to Isolate Mycobacterium bovis from Environmental Substrates during Investigations of Bovine Tuberculosis Transmission Sites (Cattle Farms and Wildlife Areas) in Michigan, USA

Table 1

Time lag between farm investigation (environmental sampling), official TB-positive date, and date of cattle depopulation. Farms identified as TB+ in 2000 and 2001 (nos. 105 and 106) were not included in this analysis.

Farm number	TB+ date	Depopulation date	Sampling date	TB+ to sampling days	Depopulation to sampling days
101	09/20/02	10/02/01	09/10/02	−10	−22
102	07/17/02	09/17/02	09/10/02	55	−7
103	07/16/02	08/21/02	09/13/02	59	23
104	06/12/02	10/29/02	09/27/02	107	−32
107	01/09/03	03/31/03	02/28/03	50	−31
108	11/27/02		03/04/03	97	Not depopulated
109	01/27/03	03/11/03	05/05/03	98	55
110	05/27/03	06/03/03	07/02/03	36	29
111	11/10/03	01/21/04	12/02/03	22	−50
112	12/23/03		03/03/04	71	Not depopulated
113	08/20/04	07/19/04	09/02/04	13	45
			Average:	56.18 days	32.67 days