Utilising Heifer Pre-mating Serology to Manage Bovine Pestivirus (BVD)
| Project start date: | 02 December 2022 |
| Project end date: | 10 July 2026 |
| Project status: | In progress |
| Livestock species: | Grass-fed Cattle, Grass-fed Beef |
| Relevant regions: | Western Australia, Mediterranean |
| Site location: | WA: South Coast Region |
Summary
This project demonstration site (PDS) project will aim to demonstrate the value of utilising serology for Bovine Pestivirus (BVD) to both define the risks specific to individual cohorts of heifers prior to mating and to guide producers to both identify and appreciate the most cost-effective intervention depending upon those results.
The overarching goal is to improve producer awareness of the pathophysiology of BVD, how it is transmitted and maintained on properties and between production systems, a greater understanding of the costs attributable to BVD infection, and a greater understanding of how serology, PI screening, vaccination, and biosecurity protocols can assist them in controlling BVD.
The project will:
- intend to demonstrate an improvement in producer understanding of the tools available to manage BVD systematically.
- intend to show an increase in the number of producers choosing to manage BVD within the study area.
- hope to show an improvement in pregnancy rate and a reduction in losses between pregnancy diagnosis and weaning on properties which choose to intervene by either vaccinating seronegative groups of heifers, by ear notch testing seropositive groups of heifers vs. producers who decide to do nothing with their serological survey results.
- map and show progress in the seroprevalence of BVD within the Esperance district over time.
- Once shown to be successful, the consultant will distribute the project findings to a wider audience to assist producers elsewhere in Australia to systematically manage BVD.
Producers involved will be able to:
- Schedule pre-mating heifer BVD serology.
- Understand how to interpret their BVD serological results.
- Understand when it is appropriate to integrate BVD vaccines into heifer pre-mating protocols.
- Understand when it is appropriate to integrate PI screening into heifer pre-mating protocols.
- Explain how BVD is transmitted and maintained within and between production systems.
- Explain how Persistently Infected (PI) animals are produced.
- Understand the role of PI’s in the spread of BVD within and between production systems.
Objectives
By December 2025, in the Esperance Region of Western Australia, 3 demonstration sites will be established, engaging 18 core producers and a minimum of 30 observer producers to:
- Conduct pre-mating BVD serology survey over three seasons on at least 30 beef enterprises located within the geographically isolated Esperance shire.
- Define the range of serological results.
- Record the proportion of core and observer producers involved in the survey that have either implemented vaccination programs or screened their replacement heifers to ensure none of them are Persistently Infected prior to mating, depending upon the results of their pre-mating serology.
- Measure pregnancy testing and calf wastage between pregnancy testing to weaning data from all properties which participate in the PDS and compare the results between the three groups (those that vaccinate, those that PI test, and those that choose to do nothing).
- Demonstrate that over the course of the PDS, a higher proportion of the replacement heifer management groups with active intervention (vaccination or PI screening) will render seronegative pre-mating serological results in subsequent annual screening indicating that their interventions have been successful compared to enterprises which chose to do nothing.
- Conduct annual field days and other activities to share the ongoing results of the annual serosurvey, pregnancy data, calf wastage data and to showcase the individual progress of the Core producers with demonstration sites encouraging ongoing adoption and enrolment amongst observer producers by the close of the project.
- Develop an economic analysis of measured losses between pregnancy testing and weaning, and potentially of pregnancy testing data, catering for differences in joining period length.
- Conduct a pre and post project KASA survey to gauge understanding of the pathophysiology of the syndrome and the steps that can be taken to mitigate it. These surveys will be used to demonstrate that a target of 100% core producers and 70% of observer producers have improved their knowledge and skills in understanding how BVD is maintained and propagated within and between production systems, affect profitability, and how to measure their risk profile of harbouring BVD in the Esperance area.
- 80% of core producers adopting a BVD management strategy and 50% of observer producers intending to adopt a BVD management strategy.
Progress
The ‘Utilising Heifer Pre-mating Serology to Manage BVDV’ Producer Demonstration Site (PDS) project is based in Esperance, WA. It commenced in 2023, with final results expected in mid 2026.
The project aims to demonstrate the value of utilising serology for Bovine Pestivirus (BVDV) to both define the risks specific to individual cohorts of heifers prior to mating and to guide producers to both identify and appreciate the most cost-effective intervention depending upon those results.
The overarching goal is to improve producer awareness of the pathophysiology of BVDV, how it is transmitted and maintained on properties and between production systems, develop a greater understanding of the costs attributable to BVDV infection, and develop a greater understanding of how serology, PI screening, vaccination, and biosecurity protocols can assist them in controlling BVDV.
The project is being driven by grower group ASHEEP & BEEF, in collaboration with Dr Enoch Bergman from Swans Veterinary Services.
Data collection from 2023 shows that of the 30 local properties screened last year in the Esperance area, four had evidence of significant exposure (indicating the possible presence of a PI heifer). Three of the four farms ear notched all their heifers, and two out of three found a PI and were able to cull her before she could cause more trouble.
In 2024, 12 properties have been screened to date (samples are still being taken), 75% of the properties revealed no exposure amongst the heifers which were screened. Of the remaining 25%, 2/3 showed strong seroconversion to BVDV (over 80%), and one partial exposure (30%).
