Decreasing Mob Size at Lambing Increases the Survival of Triplet Lambs Born on Farms across Southern Australia

Industry consultation in Australia revealed that the potential impact of the mob size of ewes during lambing on the survival of triplet-born lambs was an important research priority. Previous research has demonstrated that smaller mob sizes at lambing improve the survival of single- and especially twin-born lambs, regardless of ewe stocking rate. Therefore, we hypothesised that lambing triplet-bearing ewes in smaller mobs, regardless of stocking rate, will increase the survival of their lambs. Research sites were established on 12 commercial sheep farms across southern Australia between 2019 and 2021. One farm used Merinos whilst the remainder of the farms used non-Merino breeds, consisting of composite ewes joined to composite or terminal sires. Three of the farms were used in two years of the experiment. Adult, triplet-bearing ewes were randomly allocated into one of two treatments, ‘High’ or ‘Low’ mob size, at an average of 135 days from the start of joining. Ewe and lamb survival were assessed between allocation to treatments and lamb marking. Lamb survival was significantly greater for lambs born in the Low (65.6%) compared with the High (56.6%) mob size treatments (p p < 0.001). This study has shown that the survival of triplet-born lambs can be improved by lambing triplet-bearing ewes in smaller mobs regardless of stocking rate when ranging from 0.7–13 ewes/ha

Plant individuality: a solution to the demographer's dilemma

The problem of plant individuality is something which has vexed botanists throughout the ages, with fashion swinging back and forth from treating plants as communities of individuals (Darwin 1800; Braun and Stone 1853; Münch 1938) to treating them as organisms in their own right, and although the latter view has dominated mainstream thought most recently (Harper 1977; Cook 1985; Ariew and Lewontin 2004), a lively debate conducted mostly in Scandinavian journals proves that the issues are far from being resolved (Tuomi and Vuorisalo 1989b; Fagerström 1992; Pan and Price 2001). In this paper I settle the matter once and for all, by showing which elements of each side are correct