Characterization of Pajaroellobacter abortibovis, the etiologic agent of epizootic bovine abortion. Brooks RS(1), Blanchard MT(1), Clothier. J Vet Diagn Invest. May;14(3) Diagnosis of epizootic bovine abortion in Nevada and identification of the vector. Hall MR(1), Hanks D, Kvasnicka W. Kennedy PC, Casaro AP, Kimsey PB, Bon Durant RH, Bushnell RB, Mitchell GM. The development of the fetal lesions of epizootic bovine abortion (EBA) was.

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Identification and sequencing of the groE operon and flanking genes bpvine Lawsonia intracellularis: Furthermore, the PCR failed to amplify DNA extracted from pure cultures of a selection of bacterial pathogens typically encountered in veterinary medicine or even P.

EBA-associated lesions are chronic, developing progressively over a period of 3 months or more. Affected fetuses also have markedly elevated immunoglobulin levels, suggestive of a vigorous fetal immune response. Two specific PCRs were subsequently developed to detect these agents separately in a panel of individual bovine epizooyic tissues derived from five EBA-positive and four EBA-negative animals.

Phylogenetic identification and in situ detection of individual microbial cells without cultivation.

This study demonstrates a strong association between the presence of a novel deltaproteobacterium and the development of EBA. Thirty-six experimentally infected fetuses were recovered at periods of 29 to days after their dams had been infected by allowing the vector tick Ornithodorus coriaceus to feed on them.

The phylogenetic bvine of SerratiaButtiauxella and some other genera of the family Enterobacteriaceae. The nucleotide sequence data reported in this paper have been submitted to GenBank and have been assigned the following accession numbers: This approach was used because preliminary cloning experiments using universal bacterial primers yielded sequences identical to those of Pseudomonas sp. Published by Elsevier B. It has been hypothesized that driver-tester hybridization suppresses the amplification of ubiquitous bacterial 16S rRNA sequences, allowing unique bacterial sequences present only in the EBA-positive tissue samples to be amplified.

We acknowledge the assistance of Mike Oliver for tick collection and Richard Gniewek and Svetlana Blvine for assistance in identifying the agent in ticks and bovine tissues, respectively. In the tick studies, ticks were collected from locations where EBA was considered to be endemic, including the eastern slope of the Sierra Nevada mountain range in California and southeast Oregon, using dry ice as an attractant 614 The heifers were exposed to the agent of EBA by i natural exposure fetuses were submitted by ranchersii tick feeding under experimental conditions, or iii inoculation with tissue homogenate derived from fetuses previously diagnosed as being EBA positive.


These primer regions showed the most variation compared with other bacterial sequences in multiple-nucleotide alignments.

The sequential development of the fetal lesions was studied and the lesions compared with those in both naturally occurring and experimentally induced infections of the dams which either aborted or carried to term. Although these agents were detected in some of the Bovien samples, the pattern for neither bacterium paralleled the clinical and histopathological diagnosis of EBA data not shown. Thymuses from all seven fetuses were PCR positive.

Characterization of Borrelia coriaceae antigens with monoclonal antibodies. The gross enlargement of lymph nodes was the result of cortical follicular hyperplasia and histiocytic lymphadenitis. Acute necrotizing foci developed in several organs, but most commonly in lymph nodes and spleen.

Elizootic different fetal bovine thymic pools containing tissue homogenates from two EBA-positive tester or three EBA-negative driver individual cases were abortiom by phenol-chloroform extraction The tick lives in tree and brush litter in deer and cattle beds, feeds rapidly in less than an hour under experimental conditionsand then departs the host.

The microbe, which has yet to be successfully cultured in vitro, has proven difficult to purify from necropsy tissues. Acute vasculitis developed at the same time as the acute focal-necrotizing lesions. Isolation of a spirochete from the soft tick, Ornithodoros coriaceus, possible agent of epizootic bovine abortion. Amplicons identified on 1. Pathology of epizootic bovine abortion. Investigation of these losses has defined abortiom specific fetal syndrome characterized by late-term abortion or birth of weak or dead calves.

The inability to identify the agent in all ticks would be consistent with the low-level infection achieved by experimental transmission of EBA to cattle by tick bite. However, upon more detailed examination, all have been excluded as the probable EBA etiologic agent. Concurrent treatment with antibiotics at the time of EBA challenge abolished infection of the fetus and therefore implicated a prokaryotic organism as the likely causative agent In the fetuses which were either aborted or carried to term after prolonged infection, acute necrotizing lesions were superimposed on the chronic proliferative fetuses.


These three heifers gave birth to healthy calves; two were euthanized immediately prior to consumption of colostrum for PCR analysis; all tissues were PCR negative.

Argasidae with the exposure of cattle to epizootic bovine abortion in California. Since subsequent PCR showed that these agents were present in both EBA-positive and -negative tissues, their presence was assumed to be the result of postmortem contamination of the samples. National Center for Biotechnology InformationU.

Epizootic bovine abortion: histogenesis of the fetal lesions.

Heifer exposure n Diagnosis a No. Open in a separate window. In summary, this work demonstrates a close relationship between a novel bacterium and EBA. The majority of guidelines that have been suggested for sequence-based determination and incriminating of a presumptive microorganism in disease 5 have been satisfied.

Characterization of Pajaroellobacter abortibovis, the etiologic agent of epizootic bovine abortion.

The histologic thymic changes aabortion characteristic of EBA and included severe histocytic thymusitis with depletion of thymocytes, interlobular hemorrhage, and fibrinocellular exudation. Intracellular bacteria of porcine proliferative enteropathy: Fetuses from experimentally exposed heifers were obtained either by surgical removal following dam euthanasia captive bolt in the third trimester to days postchallenge or as dead, weak, or healthy calves following natural parturition.

In an additional experiment, six heifers were challenged with aliquots of a single thymus tissue pool previously demonstrated to be capable of transmitting EBA