B.AWW.0202 - A single shot fertility vaccine in female cattle
Current anti-fertility vaccines require at least two injections, are short acting, and can produce site reactions and granulomas.
| Project start date: | 15 April 2021 |
| Project end date: | 12 February 2025 |
| Publication date: | 30 October 2024 |
| Project status: | Completed |
| Livestock species: | Grass-fed Cattle |
| Relevant regions: | Northern Australia, Western Australia, Queensland, Northern Territory |
|
Download Report
(0.2 MB)
|
|
Summary
A practical alternative to surgical sterilisation of female cattle not required for breeding remains an unmet need in the beef industry. Anti-fertility vaccines currently available require at least two vaccinations to induce an anti-fertility response, the response is variable between cattle, and the anti-fertility response is relatively short-lived. This makes the vaccines impractical in extensive beef production where there is a particular need.
Objectives
The project evaluated whether a single vaccination with chemically defined vaccines that target specific cells in the immune system (helper T-cells) that are involved in the generation of antibodies has the potential for long-term fertility control in cattle. The two newly designed vaccines seek to induce antibodies that bind and biologically neutralise the key reproductive hormone gonadotropin-releasing hormone (GnRH).
Key findings
Vaccination with Vaccine A and Vaccine B induced an anti-GnRH antibody response in a proportion of Brahman heifers and the response was short-lived. Anti-GnRH antibody levels in blood diminished at six months in those heifers that showed a response.
Cyclic ovarian activity continued to be monitored and did not differ for vaccinated and control heifers in the 12 months after vaccination.
Benefits to industry
The vaccines assessed in this study had no safety or welfare concerns. Both Vaccines A and B induced an antibody response, but this was not sufficient to suppress ovarian activity long-term in heifers. Further research is required to identify single-dose vaccine technology that achieves a strong and sustained antibody response for long-term suppression of fertility in female cattle.
MLA action
This project overview will be published on the MLA R&D reports website.
Future research
Given the lack of a long-term antibody response in the present study to vaccination with either Vaccine A or Vaccine B, future research could include testing additional T-helper cell epitopes and larger immunogenic proteins that have multiple T-helper cell epitopes. A broader range of vaccine doses could also be tested.
More information
| Project manager: | Michael Laurence |
| Contact email: | reports@mla.com.au |
| Primary researcher: | University Of Queensland |
