Institution: | a Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California Davis, CA 95616 USA b Instituto de Investigaciones en Ciencias Veterinarias (IICV), Universidad Autónoma de Baja California (UABC), Mexicali 21100 Baja California Mexico c Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida Gainsville, FL 32610-0136 USA |
Abstract: | A case-control study was conducted in the Mexicali Valley to identify risk factors for goat-herd seropositivity for Brucella melitensis. Nineteen case herds (≥2 positive results with the 8% rose bengal plate test (RBT)) and 55 control herds (zero positive results in RBT), matched for herdsize and geographic location, were enrolled. Conditional logistic regression was used to construct a multivariable model of the odds of seropositivity using variables assessed in a questionnaire administered to goat ranchers. The final model for herd seropositivity included increased risk from importation of goats from other Mexican states, the presence of La Mancha breed does, and the presence of does born outside the herd. Increasing herdsize was also highly significant (p<0.01). In addition, a significant (p<0.05) positive association was found between the presence of seropositive dogs (as assessed by RBT) and seropositive goats on the same ranch. |