Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Bacterial and fungal causes of abortion in domestic ruminants in South Africa

Thesis (PhD (Veterinary Tropical Diseases))--University of Pretoria, 2023.

Saved in:
Bibliographic Details
Other Authors: Michel, Anita Luise
Format: Thesis
Language:English
Published: University of Pretoria 2024
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613536287457280
access_status_str Open Access
author2 Michel, Anita Luise
author_browse Michel, Anita Luise
author_facet Michel, Anita Luise
collection Thesis
dc_rights_str_mv © 2023 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Thesis (PhD (Veterinary Tropical Diseases))--University of Pretoria, 2023.
format Thesis
id oai:repository.up.ac.za:2263/96689
institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:37:42.457Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2024
publishDateRange 2024
publishDateSort 2024
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/96689 Bacterial and fungal causes of abortion in domestic ruminants in South Africa Michel, Anita Luise annelize.jonker@up.ac.za Thompson, P.N. (Peter N.) Jonker, Annelize UCTD Abortion Ruminant Chlamydia Brucella Bacteria SDG-03: Good health and well-being Veterinary science theses SDG-03 SDG-12: Responsible consumption and production Veterinary science theses SDG-12 Thesis (PhD (Veterinary Tropical Diseases))--University of Pretoria, 2023. Abortions in cattle, sheep and goats represent important economic losses in the agricultural industry. Determining causes of abortions is important for control efforts, but can be challenging. This study investigated detection methods for and significance of bacteria and fungi as agents of abortion in domestic ruminants in South Africa. Retrospective data was collected by searches of case reports (2006-2016) of participating pathology and bacteriology laboratories. During the prospective study (2017-2019), samples were analysed by a combination of conventional bacteriology methods. Quantitative real-time PCR assays for detection of the Chlamydiales, Chlamydia abortus, Chlamydia pecorum, Parachlamydia acanthamoeba and Waddlia chondrophila were created by combining primers and probes selected from literature. These assays were optimized and employed to analyse samples from 25 cases, with placentitis and/or pneumonia lesions, selected from the prospective study. The retrospective study reported 288 cases from six provinces. Diagnostic rate was 35.1%. The prospective study reported 135 cases from six provinces. Diagnostic rate was 42.2%. Brucella species were most commonly isolated in both the retrospective and prospective studies at 7.3% and 7.4% of cases, respectively. The qPCR assays detected Chlamydiales in 60% of cases with placentitis and/or pneumonia. Chlamydia abortus, P. acanthamoeba and W. chondrophila were detected in bovine; and C. pecorum and W. chondrophila in ovine and caprine cases. Chlamydiales were detected in three previously inconclusive cases. Identification was improved from genus to species level (C. pecorum). In conclusion, retrospective laboratory records yielded valuable passive surveillance data. Submission of placenta was an important factor in successful diagnosis. The most effective combination of conventional culture methods was aerobic culture together with selective Brucella, Campylobacter and fungal culture. This combination lead to improvement of the diagnostic rate in comparison with the retrospective study. Brucella abortus was the most common cause of bovine abortion over 12 years in the retrospective and prospective studies. Trueperella pyogenes was the second most common. Real-Time qPCR assays improved detection of Chlamydiales and differentiation to species level. The first detection of P. acanthamoeba and W. chondrophila in abortion cases in South Africa was reported indicating a potential role in abortions in this country. AGRISeta - ref no BC19UP57-18.1 Red Meat Research and Development South Africa - ref no 1395058846 Veterinary Tropical Diseases PhD (Veterinary Tropical Diseases) Unrestricted Faculty of Veterinary Science SDG-03: Good health and well-being SDG-12: Responsible consumption and production 2024-06-27T07:40:17Z 2024-06-27T07:40:17Z 2024-09 2023-11-10 Thesis * S2024 http://hdl.handle.net/2263/96689 https://repository.up.ac.za/submit?workspaceID=114239 en © 2023 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle UCTD
Abortion
Ruminant
Chlamydia
Brucella
Bacteria
SDG-03: Good health and well-being
Veterinary science theses SDG-03
SDG-12: Responsible consumption and production
Veterinary science theses SDG-12
Bacterial and fungal causes of abortion in domestic ruminants in South Africa
title Bacterial and fungal causes of abortion in domestic ruminants in South Africa
title_full Bacterial and fungal causes of abortion in domestic ruminants in South Africa
title_fullStr Bacterial and fungal causes of abortion in domestic ruminants in South Africa
title_full_unstemmed Bacterial and fungal causes of abortion in domestic ruminants in South Africa
title_short Bacterial and fungal causes of abortion in domestic ruminants in South Africa
title_sort bacterial and fungal causes of abortion in domestic ruminants in south africa
topic UCTD
Abortion
Ruminant
Chlamydia
Brucella
Bacteria
SDG-03: Good health and well-being
Veterinary science theses SDG-03
SDG-12: Responsible consumption and production
Veterinary science theses SDG-12
url http://hdl.handle.net/2263/96689
https://repository.up.ac.za/submit?workspaceID=114239