Source: UNIV OF CALIFORNIA (VET-MED) submitted to
HOST/ VECTOR/ENVIRONMENTAL INTERACTIONS IN EPIZOOTIC BOVINE ABORTION
 
PROJECT DIRECTOR: STOTT, J. L.
 
PERFORMING ORGANIZATION
PATHOLOGY, MICROBIOLOGY & IMMUNOLOGY
UNIV OF CALIFORNIA (VET-MED)
DAVIS,CA 95616
 
NON TECHNICAL SUMMARY: Epizootic bovine abortion (EBA), or foothill abortion as it is often termed, is considered to be one of the major health problems facing the California and Nevada beef industries. EBA is characterized by late-term abortion or birth of weak calves and is diagnosed pathologically. EBA is caused by a poorly characterized, and as yet uncultured, bacteria that is transmitted to susceptible pregnant heifers in foothill regions of California and parts of Nevada and Oregon by the soft-shelled tick, Ornithodoros coriaceus. This project will document in detail the distribution of the tick vector and the etiologic agent of EBA across an environmentally diverse study area containing many of the major vegetation types characteristic of the Western US. A recently developed molecular probe will be used to detect the etiologic agent in ticks. Remote sensing and geographic information system (GIS) data sets will be used to ensure effective and efficient representation by field sampling across environmental gradients. Such information will be invaluable in further defining the likely geographical extent of the vector and pathogen, and the potential role of EBA as an unidentified production problem in previously unstudied areas.
 
OBJECTIVES: Select representative samples sites within an environmentally diverse study area to collect the tick vector, Ornithodoros coriaceus, of epizootic bovine abortion (EBA). Optimize parameters for identification of the EBA etiologic agent in ticks. Collect the tick vector, Ornithodoros coriaceus, at the sample sites, as defined in the first objective, and test for the presence of the etiologic agent of EBA.
 
APPROACH: The long term goal of this project is to define the ecology of epizootic bovine abortion (EBA). Our approach is to utilize geographical data to facilitate the delineation of host-vector-pathogen interactions. This project will utilize recently developed molecular probes to detect the etiologic agent in the tick vector for the purpose of defining environmental factors that are correlated with the presence of the tick vector and the EBA pathogen. Remote sensing and geographic information system (GIS) data sets will be used to ensure effective and efficient representation by field sampling across environmental gradients.
 
CRIS NUMBER: 0192616 SUBFILE: CRIS
PROJECT NUMBER: CALV-CG02-3520412365 SPONSOR AGENCY: CSREES
PROJECT TYPE: NRI COMPETITIVE GRANT PROJECT STATUS: TERMINATED MULTI-STATE PROJECT NUMBER: (N/A)
START DATE: Sep 1, 2002 TERMINATION DATE: Aug 31, 2006

GRANT PROGRAM: SUSTAINING ANIMAL HEALTH & WELL BEING
GRANT PROGRAM AREA: Animal Systems

CLASSIFICATION
Knowledge Area (KA)Subject (S)Science (F)Objective (G)Percent
311331011004.210%
311331011304.220%
311331011704.270%

CLASSIFICATION HEADINGS
KA311 - Animal Diseases
S3310 - Beef cattle, live animal
F1130 - Entomology and acarology
F1100 - Bacteriology
F1170 - Epidemiology
G4.2 - Reduce Number and Severity of Pest and Disease Outbreaks


RESEARCH EFFORT CATEGORIES
BASIC 10%
APPLIED 90%
DEVELOPMENTAL (N/A)%

KEYWORDS: foothill abortion; ornithodoros coriaceus; epizootic diseases; ixodidae; geographic information systems; disease vectors; environmental factors; host parasite relations; animal diseases; beef cattle; epidemiology; insect collection; optimization; etiology; pathogen identification; parameters; disease detection; host pathogen relations; remote sensing

PROGRESS: Sep 1, 2002 TO Aug 31, 2006
A variety of different geographical areas in California, Oregon and Nevada, with varying types of vegetation, have been inspected for the presence of Ornithodoros coriaceus, the tick vector of epizootic bovine abortion (EBA). The greatest numbers of ticks have been trapped in juniper and pinion. Minimal ticks have been trapped in evergreen and none in sage. Ticks from all areas and vegetation types have been analyzed for the presence of the bacterial pathogen (agent of EBA, aoEBA) using a polymerase chain reaction (PCR). No apparent associations between the percentage of ticks infected and vegetation type, geographical location and elevation were identified. The percentage of ticks infected with aoEBA from a single geographic site varied between two consecutive years. No data was obtained that would suggest increased numbers of blood meals results in increased frequency of infection. Attempts to increase the percentage of ticks in which aoEBA could be identified by providing a "clean" blood meal were unsuccessful.

IMPACT: 2002-09-01 TO 2006-08-31 Provided extensive information on pathogen/vector/host interactions relative to the bacterial agent that causes foothill abortion (epizootic bovine abortion). Suggested the source of infection for the tick vector is probably not mammalian.

PUBLICATION INFORMATION: 2002-09-01 TO 2006-08-31
Chen CI, KP King, MT Blanchard, MR Hall, BM Aldridge, L Bowen and JL Stott. Identification of the etiologic agent of epizootic bovine abortion in field-collected Ornithodoros coriaceus Koch ticks. Vet Microbiol, 2007, In Press

PROJECT CONTACT INFORMATION
NAME: Stott, J. L.
PHONE: 530-752-3349
FAX: 530-752-3349