Ovine enzootic abortion (OEA) remains a major problem in sheep-rearing countries despite the availability of protective vaccines. The causative agent, Chlamydophila abortus, is a Gram-negative bacterium that can induce a persistent, subclinical infection in non-pregnant sheep. The development of a new safe, effective and practical vaccine requires a detailed understanding of host-pathogen interactions and the identification of clear correlates of protection. Since disease (abortion) is only observed during pregnancy, the nature of host immunity to C. abortus and the specialised immunological features that permit maternal acceptance of the semi-allogeneic fetus are central to the pathogenesis of OEA. We review the current literature on persistence of C. abortus, host immunity to infection and mechanisms of abortion. We identify the key outstanding questions surrounding OEA and discuss the current knowledge gaps with a view to developing improved control strategies.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.vetmic.2008.09.030 | DOI Listing |
Vaccines (Basel)
January 2025
Moredun Research Institute, Pentlands Science Park, Penicuik, Midlothian EH26 0PZ, UK.
Background/objective: , the cause of ovine enzootic abortion, is a zoonotic bacterial pathogen and one of the most infectious causes of foetal death in sheep worldwide. Although the disease can be controlled using commercial inactivated and live whole-organism vaccines, there are issues with both, particularly concerning efficacy and safety. Recently, we have described the development of a new COMC (chlamydial outer membrane complex) vaccine based on a detergent-extracted outer membrane protein preparation of the pathogen, which can be delivered in a single inoculation and is both efficacious and safe.
View Article and Find Full Text PDFVet Ital
January 2025
University Hospital College, University of Ibadan, Nigeria.
The advancement of small ruminant farming in Benin has encountered challenges associated with health issues and agricultural practices. This study aimed to provide the initial documentation of the prevalence of enzootic ovine abortion and evaluate the health status of animals concerning various recurring diseases on traditional small ruminant farms in Benin. In 2023, a semi-structured survey of 450 farms was carried out in two agricultural development centers in Benin.
View Article and Find Full Text PDFBMC Res Notes
December 2024
Ethiopian Institute of Agricultural Research, National Agricultural Biotechnology Research Center, P.O. Box: 249, Holeta, Ethiopia.
Background: The reproductive problem is an animal health-related bottleneck that constrains livestock genetic improvement efforts in tropical countries such as Ethiopia. The infectious causes of reproductive disorders are one cause of decreased reproductive efficiency. This study aimed to determine the seroprevalence to Bovine Herpesvirus-1 (BHV1), Bovine Viral Diarrhea Virus (BVDV), Neospora caninum (N.
View Article and Find Full Text PDFEpidemiol Infect
December 2024
Department of Virology, Veterinary Faculty, Necmettin Erbakan University, Konya, Türkiye.
Abortion is one of the major threats to the livestock industry, and it also poses significant threats to public health since some of the abortifacient agents are considered zoonotic. (), (), (), and Cache Valley virus (CVV) are recognized as important zoonotic and abortifacient agents of reproductive failure in small ruminants. This study determined the prevalence of these agents in ovine and caprine foetuses in Türkiye.
View Article and Find Full Text PDFMicrobes Infect
December 2024
Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, USA. Electronic address:
We investigated if the efficacy of a Chlamydia abortus (Cab) subunit vaccine is influenced by route of administration. Thus, female CBA/J mice were immunized either by mucosal or systemic routes with Vibrio cholerae ghost (VCG)-based vaccine expressing T and B cell epitopes of Cab polymorphic membrane protein (Pmp) 18D, termed rVCG-Pmp18.3.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!