Doing the numbers on ewes
11 March 2016
A research project announced this week is set to break new ground in ewe management in a bid to further lift lamb survival and improve weaning rates.
Recognising the critical importance of reproductive success in the Australian sheep industry, Meat & Livestock Australia (MLA) and Australian Wool Innovation (AWI) are collaborating to examine the effect of mob size and stocking density at lambing on lamb survival and weaning rates.
The research, led by the Victorian Department of Primary Industries, will take place on commercial prime lamb and wool growing properties with 70 individual project sites to be established over two years. The locations will be across Western Australia, Victoria, South Australia and NSW to allow for a natural variation in other animal, management and environmental influences, and opportunities to expand the work into other states are being explored. Each of these sites will also be linked to a network of existing producers.
This project will be managed by AWI reproduction specialist and Associate Professor of Animal Science at Murdoch University Dr Andrew Thompson, who was one of the original developers of Lifetime Ewe Management (LTEM), and who managed the preceding AWI-funded Lifetime Wool Production program. According to Andrew, this initiative aligns well with the national RD&E priorities and investment plan for sheep reproduction developed by MLA, and fills an important knowledge gap.
“We will deliver improved recommendations for sheep producers regarding the allocation of ewes to paddocks, paddock size, stock density and feed on offer during lambing," he said.
"It will assist producers to make more informed decisions about the cost benefit of investing funds in paddock subdivision to improve reproductive performance and farm profitability.
“If we succeed as expected, the pay offs for the industry will potentially be massive - improving the survival of single lambs by just 5% and twin lambs by 10% would improve industry wide farm profit by $250 million per annum’."
This initiative is expected to deliver the basis for the next level of reproductive performance improvement for graduates of the very successful Lifetime Ewe Management course (LTEM), funded by AWI and delivered nationally through Rural Industries Skill Training.
MLA Manager Genetics and Sheep R&D Program Richard Apps said, while many producers recognised that smaller mob size at lambing is desirable, factors such as the number of lambs born each day and their proximity also impact survival, meaning there is further opportunity to refine management to continue to improve weaning rates.
"The result will be not only improved animal welfare outcomes for both ewes and lambs, but the ability to establish the most effective lambing paddocks to increase weaning rates contributing to improved productivity and profitability for the sheep industry," Richard said.
According to AWI’s General Manager of Research, Dr Paul Swan, “The LTEM Program has typically been transformative for the growers who have graduated. The 2,100 AWI-funded LTEM graduates have on average improved their weaning rates by 7-10%, and simultaneously reduced their ewe mortality rates, by assessing and optimising ewe condition score, and identifying and differentially managing twin bearers.
“Yet while these performance gains are substantial, evidence has been mounting that the density of lambing ewes in the lambing paddock could also be having an influence on lambing outcomes, particularly the risk of mis-mothering.”
With existing best practices widely adopted across these businesses, researchers are confident that by filling this gap in the knowledge of the effects of lambing density, stocking rate and flock size on lamb survival, a new set of tools will be generated to lift lamb survival to the next level.
