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Context Data collected from producers in south-eastern Australia found that the survival of twin-born lambs decreased by 3.5% for each extra 100 ewes in the mob at lambing. Increasing stocking rate by 1 ewe/ha decreased lamb survival by a further 0.7%. These survey findings suggest that lamb survival could be improved by optimising the allocation of ewes to mobs and paddocks at lambing. Aim The present paper reports two experiments. Experiment 1 tested the hypotheses that (1) the survival of twin-born lambs would be greater when ewes lamb in smaller mobs and at lower stocking rates, and (2) the effects of mob size and stocking rate would be greater in Merinos than in non-Merino breeds. Experiment 2 tested the hypothesis that the survival of twin-born Merino lambs would be greater at lower mob sizes when ewes lambed at stocking rates

Improving the reproductive performance of sheep is a national research priority, but identifying which components of the reproductive process should be the highest priority for further research is complex. The analysis reported in this paper tested the hypothesis that research areas can be prioritised using knowledge of potential gains and bio-economic modelling of critical control points. The analysis was carried out in two parts and the control points included increasing conception, increasing survival of single- or twin-born lambs, increasing survival of ewes at lambing, increasing weaner survival and increasing early reproductive success. For each control point, four productivity levels were examined and the average change in profit per unit of change in the control point per animal was calculated for three flock types. The second component quantified the potential industry gain from the change in profit per unit in each control point, the potential for change (number of units) and the potential adoption (number of ewes or weaners). On the basis of the assumptions used, increasing survival of twin-born lambs was the area with the highest pay-off and had an estimated value of AU$515 million. The value of increasing twin-lamb survival compared with single-lamb survival was affected by the proportion of single- and twin-bearing ewes in the flock. In a flock based on maternal ewes, there are relatively more twin-bearing ewes, so increasing twin survival was a higher priority than for flocks based on Merino ewes in which the proportion of twins was lower. The analysis suggested that the second most important area for future research was improving reproduction from ewe lambs with a pay-off of AU$332 million, followed by improving survival of ewes AU$303 million, improving survival of single born lambs AU$285 million, improving the number of lambs conceived AU$235 million, improving reproduction from 2-year-old ewes AU$221 million and, finally, improving weaner survival AU$52 million. The priorities determined using this method were robust and varying the assumptions of the bio-economic analysis had little impact on the priorities. There was no change in the overall ranking of the critical control points from either increasing the meat or wool price by 20% or altering the flock structure of the Merino flock. Therefore, we can be confident that the priorities determined in the present analysis with current prices and production systems will be valid in to the future.

Lifetime Ewe Management is an extension program designed to assist sheep producers to improve their understanding of ewe nutrition and to develop the skills and confidence to improve their management. The course is based on a small-group extension model and was developed by the Lifetimewool project as a way to incorporate the research findings, economic modelling and producer guidelines developed by the project. Lifetime Ewe Management commenced in Victoria in the spring of 2006 and by the end of 2010, 221 producers had completed the 2-year program. The changes in knowledge, attitudes, skills, aspirations and management practices of 182 of these participants were examined. Participants of the Lifetime Ewe Management program increased their whole-farm stocking rates by 14%, increased lamb marking percentages by 11–13% depending on enterprise type, and decreased ewe mortality rates by 43%. These improvements resulted from a significant change in the perceived importance of managing ewes to condition-score targets to improve profitability and increases in the ability of participants to condition score ewes, assess pasture quantity and quality and feed budget. These changes were consistent regardless of how innovative the participants were at the beginning of the program. The appeal and success of the program was attributed largely to the small-group model where producers worked with their own flock under the guidance of a skilled facilitator and with access to effective decision-making tools. The Lifetime Ewe Management program design provides a blueprint for future extension programs striving to achieve widespread practice change.