ON FARM SHEEP REPRODUCTIVE EFFICIENCY8 Putting precision us to do further work to see if into lambing there’s a point at which feed RESEARCH IN on offer overrides the effect REVIEW Tim Leeming is a long-time advocate of of mob size on lamb survival,” running multiple-bearing ewes in small Amy said. PROJECT NAME mobs at lambing. “Understanding any factors Improving lamb which influence the survival by optimising His triplet-bearing ewes typically lamb in mobs of relationship between mob lambing density 8–20, while twin-bearing ewes lamb in mob sizes of size and lamb survival will 45–55. Single-bearing ewes can lamb in mobs of up RESEARCH to 800 head. help us develop improved ORGANISATIONS guidelines for producers.” Agriculture Victoria, Tim and his wife Georgie collect significant data on Murdoch University, their lambing mobs, which they have provided to the Amy Lockwood Landmark, Elders, lambing density research project (see story opposite). T: 0429 976 483 University of Adelaide, E: a.lockwood@ Department of Primary The smaller the better murdoch.edu.au Industries NSW Tim has been scanning for multiple lambs since 1995 and has differentially managed single and For help with maximising FUNDING multiple-bearing ewes for 20 years. lamb numbers go to ORGANISATIONS Module 10 of Making AWI and MLA “There are a lot of variables that can come into play More From Sheep: but, generally speaking, the smaller your mob sizes GOAL for multiple-bearing ewes in our part of the world makingmorefromsheep. To quantify the effects of com.au/wean-more- mob size and stocking (higher rainfall, higher stocking rates), the better your lambs/index.htm rate at lambing on lamb lamb survival,” Tim said. Or consider a Bred Well survival on commercial “That’s shown by 20 years of my diaries and Fed Well workshop near farms across southern spreadsheets, which show if you can take a multiple- you: mla.com.au/ Australia. It will contribute bearing mob size of 150 back to three mobs of Bred-Well-Fed-Well to the development of 50 each, you’ll probably pick up 10% extra lambs, practical guidelines, everything else being equal. Want to know more? including cost–benefit analysis, for producers. “My records also show no benefit to smaller mobs Amy Lockwood explains for single-bearing ewes, but I’ll still put them in a her findings on Improving BUDGET protected paddock and give them half the amount of lamb survival by reducing $741,006 + $479,717 feed as a twin-bearer to protect them from dystocia.” mob size at lambing in an in-kind MLA Sheep Productivity Changing tack and Profitability DURATION Tim has changed several ewe management practices webinar at youtube. 2015–2019 in the past 20 years, with shorter joinings being the com/meatandlivestock KEY FINDINGS main one. (search videos). TO DATE Decreasing mob size by “We’ve gone from a six-week joining 20 years ago, 100 twin-bearing ewes down to three joinings of 17 days each, with 20-day at lambing increases the breaks in between,” he said. survival of their lambs by “Last year, out of just under 7,000 ewes joined, we 2%, regardless of breed had 1.7% dry. The year before we had 2.1% dry, so and the starting size of even though it sounds risky, it’s not. the mob. There was no effect of stocking rate at “The end result is that we’re not lambing over a longer lambing on lamb survival. time than we used to 20 years ago, but we’re using scanning technology to be more strategic 27