Association between soil type and paratuberculosis in cattle herds.
OBJECTIVE
To determine the association between soil type and paratuberculosis in cattle.


METHODS
Soil samples and test results for paratuberculosis in 92 Indiana cattle herds.


METHODS
Testing records from herds in which > or = 20 cattle were tested for paratuberculosis by use of an ELISA between 1998 and 2002 were identified. Soil type was characterized on the basis of herd location. Clusters of herds with seroprevalence greater than the median seroprevalence were identified. Association between clusters and soil types was estimated by logistic regression, adjusted for herd type (dairy or beef).


RESULTS
A spatial cluster of greater than the median seroprevalence was identified in northeast Indiana. Soils with low silt content were associated (odds ratio [OR], 7.2; 95% confidence interval [CI], 2.1 to 24.5) with this cluster. Adjusting for herd type did not substantially alter this association (OR, 6.7). Herds located in areas with sandy loam (OR, 6.2; 95% CI, 1.4 to 27.4) and loam (OR, 3.6; 95% CI, 1.0 to 13.2) soils were also more likely to be within the cluster of greater than the median seroprevalence. Herds located in areas of silt loam soils were less likely (OR, 0.2; 95% CI, 0.1 to 0.7) to be included in this cluster.


CONCLUSIONS
Spatial distribution of herds with greater than the median seroprevalence of paratuberculosis was associated with soil characteristics. Survival of Mycobacterium avium subsp paratuberculosis may be enhanced by silt or sand content in loamy soils. These results may be used to modify paratuberculosis control programs.
Ward
Michael P
MP
Department of Veterinary Pathobiology, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907-2027, USA.
Perez
Andres M
AM
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology*; D016000:Cluster Analysis; D004797:Enzyme-Linked Immunosorbent Assay; D007196:Indiana; D016013:Likelihood Functions; D016015:Logistic Models; D009010:Monte Carlo Method; D010283:Paratuberculosis / Q000453:epidemiology*; D012987:Soil
D012987:Soil