Understanding cattle loss during pregnancy through bacterial infection
Lead Research Organisation:
University of Nottingham
Department Name: School of Veterinary Medicine and Sci
Abstract
Impact: The intracellular pathogen Salmonella enterica serovar Dublin is of major importance to global food security. As a foodborne pathogen Salmonella Dublin is of public health concern but also impacts on the reproductive performance of beef and dairy cattle. Salmonellosis causes production losses due to abortion, veterinary bills, delayed conception, compromising herd health and reducing milk yield after abortion, with an average cost of £630 per abortion in a dairy herd (Cabell, 2007).
Background: Salmonella is an intracellular pathogen and expresses a wide range of virulence factors to escape and modulate the host response (Hurley et al 2014). S. Dublin is a host adapted pathogen of cattle causing mainly diarrhea, pneumonia and death in calves and adult cattle as well as abortion and decreased milk yield in cows (Nielsen 2013). Only limited data are available on S Dublin's effects on the bovine reproductive system.
Instead of a single placenta, ruminants have multiple placentomes (or button placentas) with fetal cells organized in cotyledons interacting with the maternal caruncular cells. Prior to abortion the highest numbers of S Dublin have been found in the placentomes with rapid multiplication of S. Dublin in the connective tissue of the cotyledon (Hall & Jones 1976).
Hypothesis: Salmonella Dublin modulates the innate immune response to allow colonization of the bovine placentome.
Programme of work:
1. Development of tissue culture model for host pathogen interactions of the bovine placentome using established cell culture models of bovine caruncular epithelial cells (BCEC).
2. Characterisation of the host response to infection with S. Dublin using BCEC (bacterial invasion and survival, host innate immune response).
3. S. Dublin growth and survival in bovine serum & whole blood.
4. Development of a placentome ex vivo organ culture (EVOC).
5. Characterisation of S. Dublin invasion, histopathology caused by invasion of and replication in the EVOC bovine placentome and the host response.
6. Investigating the role of bacterial virulence factors in infection and the host response.
In-depth knowledge of S. Dublin and its interaction with the host at cellular level will contribute to the development of innovative approaches to disease control, such as modulating host response
Background: Salmonella is an intracellular pathogen and expresses a wide range of virulence factors to escape and modulate the host response (Hurley et al 2014). S. Dublin is a host adapted pathogen of cattle causing mainly diarrhea, pneumonia and death in calves and adult cattle as well as abortion and decreased milk yield in cows (Nielsen 2013). Only limited data are available on S Dublin's effects on the bovine reproductive system.
Instead of a single placenta, ruminants have multiple placentomes (or button placentas) with fetal cells organized in cotyledons interacting with the maternal caruncular cells. Prior to abortion the highest numbers of S Dublin have been found in the placentomes with rapid multiplication of S. Dublin in the connective tissue of the cotyledon (Hall & Jones 1976).
Hypothesis: Salmonella Dublin modulates the innate immune response to allow colonization of the bovine placentome.
Programme of work:
1. Development of tissue culture model for host pathogen interactions of the bovine placentome using established cell culture models of bovine caruncular epithelial cells (BCEC).
2. Characterisation of the host response to infection with S. Dublin using BCEC (bacterial invasion and survival, host innate immune response).
3. S. Dublin growth and survival in bovine serum & whole blood.
4. Development of a placentome ex vivo organ culture (EVOC).
5. Characterisation of S. Dublin invasion, histopathology caused by invasion of and replication in the EVOC bovine placentome and the host response.
6. Investigating the role of bacterial virulence factors in infection and the host response.
In-depth knowledge of S. Dublin and its interaction with the host at cellular level will contribute to the development of innovative approaches to disease control, such as modulating host response
Organisations
| Description | Characterised 16 Salmonella enterica serovar Dublin isolates using phenotypic and genotypic methodologies. This included whole genome sequencing and identification of virulence factors and antimicrobial resistance genes. These isolates were used to infect a tissue and host-specific model of the bovine reproductive tract, demonstrating bacterial virulence and aided in understanding the host response to infection using molecular techniques. Finally, investigation of bacterial dissemination was conducted using whole blood studies and S. Dublin isolates. |
| Exploitation Route | Further work can be conducted on the S. Dublin isolates investigating virulence factors specifically and looking at genomic markers for divergence in bacterial lineage due to host-specificity. Additionally, more work can be done to investigate the host response to infection, either in the cell culture model used in the thesis, or using a more complex model of the bovine reproductive tract like tissue biopsies of the placentome. |
| Sectors | Agriculture, Food and Drink |
| Description | Society Conference Grants - Annual Conference 2018 |
| Amount | £233 (GBP) |
| Organisation | Microbiology Society |
| Sector | Learned Society |
| Country | United Kingdom |
| Start | 04/2018 |
| End | 04/2018 |
| Description | Society Conference Grants - Annual Conference 2019 |
| Amount | £238 (GBP) |
| Organisation | Microbiology Society |
| Sector | Learned Society |
| Country | United Kingdom |
| Start | 04/2019 |
| End | 04/2019 |
| Description | Society Conference Grants - Annual Conference 2020 |
| Amount | £240 (GBP) |
| Organisation | Microbiology Society |
| Sector | Learned Society |
| Country | United Kingdom |
| Start | 04/2020 |
| End | 04/2020 |
| Description | SB Fest Discovery Zone |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Organised 15+ outreach activities and groups to participate in the Discovery Zone which was visited by around 800 members of the public, undergraduates and postgraduates. |
| Year(s) Of Engagement Activity | 2018,2019 |