ON FARM SHEEP REPRODUCTIVE EFFICIENCY8 To join or nottojoin? “It also quantified the New decision‑support tool impacts of live weight and Andrew said a age‑at‑joining on the survival decision‑support tool has of the ewe lamb dam and her been developed to help progeny, carryover effects producers and consultants on the ewe’s performance determine how mating when joined at 19 months, ewe lambs should be and the productivity of evaluated alongside other her progeny. production alternatives. “While there are still some “The tool also determines the knowledge gaps, we know a optimal management system lot more than we did and this for an enterprise mating ewe is what allowed us to model lambs, together with the the cost‑effectiveness of impacts on profitability of joining ewe lambs.” sub‑optimal management,” The results are in he said. The economic analysis “It’s in the prototype stage was carried out for Merino now and we’re aiming to and maternal ewe lambs have it in limited use by the in three different regions, end of the year.” and for autumn and spring‑lambing flocks. Supporting extension and adoption I ncreasing the number of ewes mated to lamb at Results included the In preparing the project’s 12–14 months can be an effective way to build following: final report, Andrew and replacement ewe numbers, increase lamb supply • Mating maternal ewe lambs economic analyst John and boost farm profitability – particularly with was profitable in all regions Young summarised their maternal breeds in high‑rainfall areas. and times of lambing major findings into draft key The project drew on examined. messages for improving the An MLA‑funded research reproductive performance of project, led by Dr Andrew prior MLA and Murdoch • Joining maternal ewe lambs Thompson from Murdoch University‑funded research was more profitable than ewe lambs. University, used economic into joining ewe lambs. It joining Merino ewe lambs. These will be refined based modelling to guide the was made possible with the • Profits from joining ewe on testing of the tool, then decision‑making process contribution of significant lambs were greater in shared via existing extension behind whether or not to join data sets from Cashmore environments with a longer and adoption programs maternal or Merino ewes at Oaklea Performance growing season, regardless and materials, including seven to nine months of age. Maternals (see story of ewe breed. MLA Tips & Tools, Bred opposite) in south‑west • Joining maternal ewe Well Fed Well and Profitable “Joining ewe lambs is not for Victoria and Moojepin lambs was not sufficiently Grazing Systems. ■ everyone,” Andrew said. Multi‑Purpose Merinos in profitable to be a priority “You need to have the right WA’s Great Southern region. in wheatbelt regions with Dr Andrew Thompson sheep, be operating in the Ewe lamb focus low rainfall. T: 08 9360 6000 right environment with the Andrew said the earlier work • It was more profitable to The full report can be right season, and be doing quantified the effects of join ewe lambs at eight downloaded at: everything else right before sire genetics on ewe lamb months of age, rather than mla.com.au/ you consider this option.” reproductive performance. seven months. yearlinglambs Andrew said producers It showed reproductive rate • The economic optimum was should first consider whether increased by about 4% per for live weight at joining to there are other production extra kilo of live weight at be around 75% of mature issues that are likely to joining (when below 45kg). weight (42–45kg) and, have a higher pay‑off, “The earlier research found for all scenarios, feeding including improving pasture that improving the nutrition to gain more weight production and utilisation, or of ewe lambs during joining during joining itself was improving reproduction from also increased reproductive more profitable. mature or hogget ewes. rate,” he said. 14