P.PSH.0808 - New approaches to the understanding of underlying causes for neonatal lamb mortality
Increased twinning rates have led to higher weaning rates from both Merino and Maternal cross ewes.
| Project start date: | 27 June 2017 |
| Project end date: | 30 May 2022 |
| Publication date: | 06 May 2024 |
| Project status: | Completed |
| Livestock species: | Sheep, Lamb |
| Relevant regions: | National |
Summary
This project will look at the contributions of sire breed and metabolic state of the pregnant ewe to the incidence of dystocia. It will: refine sensor methodology to detect the parturition event and measure the duration; scale up the number of devices available; investigate the contribution of metabolic energy balance to lambing behaviour; investigate the link between prolonged parturition and metabolic markers and their influence on the incidence of dystocia. Focus will be given to twin bearing ewes, using both Merino and maternal crosses, as multiple pregnancies are at highest risk of resulting in high neonatal losses. In the second stage, the new parturition sensing tool and biomarkers identified in the first stage will be applied in a research population at CSIRO to establish correlation of lambing outcomes with biomarkers and parturition length on ewes. If successful, this measurement will be used in a larger research population to validate the correlation of the new measurements and lambing outcomes. The project will produce data on which basis it will be feasible to investigate the potential to include a sensor based or biomarker trait into selection indices.
Objectives
This objectives of this project are split across two stages:
Stage 1:
• Refine the parturition detection and duration or difficulty sensor device to a level where it can be scaled up and used on paddock to detect parturition and measure duration; establishing normal distribution of duration and incidence of prolonged labour/dystocia.
• Establish variation of metabolic effects of stressors on the ewe (iStat blood gas, blood glucose, lactate, and metabolites); starting to investigate effects on lambing outcomes.
Stage 2:
• Estimated variation in the response of ewes to metabolic stressors and effects on lambing outcomes.
• Development of a new phenotype for lamb survival in the form of parturition duration or lambing ease.
Recommendations for producers on management options for the management of ewes to improve lamb survival, in conjunction with improved genetic selection.
Key findings
Movement sensors can be used to detect date of birth for lambs. Behavioral differences have been found for dystocic ewes and dystocia can be detected in principle from movement data. Dystocia affects the maternal care behaviour of ewes. There are physiological blood signatures for dystocia which appear to be influenced by environmental conditions.
Benefits to industry
The results from this project support the development of a commercial device to detect date of birth which has value to sheep breeders. Further development of a method to detect dystocia will enable research efforts addressing dystocia to achieve higher impact by supporting more targeted research. Development of commercial devices detecting dystocia will enable producers to evaluate their own efforts to manage ewes and select rams for improved lamb survival.
MLA action
Publishing of the final report on the MLA R&D website.
Future research
Key recommendations for future research and development:
• support validation of date-of-birth algorithm; establishing pathway to market
• support development of additional metrics to augment dystocia detection
• support evaluation of economic benefits for development of a smart tag for sheep to prioritise research efforts.c
More information
| Project manager: | Sharon Dundon |
| Contact email: | reports@mla.com.au |
