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Higher stocking rates of lambing ewes have been associated with poorer ewe-lamb behaviour and lamb survival. This study tested the hypothesis that increasing the mob size and stocking rate of lambi...

The objectives of this study were to validate the application of Bluetooth technology to determine maternal pedigree and to determine ewe–lamb spatial relationships in extensive farming systems. A total of 35 first-cross Merino ewes (Merino × Border Leicester and East Friesian) and 23 of their lambs aged 1 to 3 wk were fitted with activity monitors equipped with Bluetooth (BT) technology (ActiGraph wGT3X-BT) by means of halters and collars, respectively. The BT devices on lambs were programmed to receive wireless signals once every minute from nearby BT units on ewes, which were programmed as beacons sending BT signals 4 times every second. Ewes and lambs fitted with sensors were dispatched into the paddocks, and after 10 d, the sensor units were retrieved and the BT signals received by lambs were downloaded using the ActiGraph software. The maternal pedigree of the lambs was determined as the ewe from which the lamb received the most BT signals. The distance between the lamb receiving the signal and the ewe sending the signal was estimated from the strength of BT signal received. The pedigree determined by BT was compared with the pedigree determined by DNA profiling and verification. The results showed that the accuracy of maternal pedigree determined by BT signals reached 100% within the first 15 min of returning animals to pasture of ewes and lambs fitted with sensors. Maternal signals (counts/d) received by 1-, 2-, and 3-wk-old lambs were 617 ± 102, 603 ± 54, and 498 ± 36, respectively, and the corresponding nonmaternal signals received were 140 ± 27, 106 ± 30, and 155 ± 39, respectively. Maternal signals received during the dark period were significantly higher than the maternal signals received during the light period (P < 0.05). Maternal signals received during the light period by 3-wk-old lambs were significantly lower when compared with those received by 1- and 2-wk-old lambs. Over 90% of the BT signals received from within 2 m of the lamb were from its mother. The maternal BT signals expressed as a portion of total BT signals decreased with increasing distance from the lamb. The results show that BT wireless networking is a fast and reliable method for the determination of maternal pedigree of lambs in extensive farming systems. In addition, wireless BT technology is also useful in determining mother–offspring spatial relationships.

At least 25% of lambs born in Australia die before marking. Research across southern Australia has demonstrated that reducing mob size at lambing by 100 ewes will, on average, increase the survival of single-born lambs by 0.8% and twin-born lambs by 2.2%. In this paper we assessed the economic value of lambing ewes in smaller mobs to improve lamb survival. The analysis considered scenarios for Merino and non-Merino flocks where producers subdivided lambing paddocks using temporary or permanent fencing, or where ewes were reallocated within existing paddocks based on ewe pregnancy status. Optimum mob sizes were most sensitive to the type of fencing used for subdivision, whether ewes were single- or twin-bearing, whether the effect of paddock size on potential stocking rate was included and the target return on investment. Breed, ewe stocking rate, scanning percentage and lamb price also impacted optimum mob size but had a smaller effect. The optimum mob size for twin-bearing Merino and non-Merino ewes was between 34% and 60% that of single-bearing ewes and this was similar for scenarios where paddocks were subdivided or ewes were reallocated within existing paddocks. Permanent subdivision of paddocks also presents an opportunity to increase stocking rate by capitalising on the benefits of improved pasture utilisation in smaller paddocks. The relationship between paddock size and pasture utilisation is not well quantified but it has an important effect on optimum mob and paddock size. The value of reallocating ewes within existing paddocks was greatest at a scanning percentage of 150% as this presents the greatest opportunity to alter mob sizes for single- and twin-bearing ewes. The economic return from adjusting the relative mob size of twin-bearing ewes from 100% to 50% that of single-bearing ewes was up to $0.27/Merino ewe/yr and $0.44/non-Merino ewe/yr with lamb at $6/kg carcass weight. Overall, these analyses demonstrate that reducing mob size at lambing can be a profitable strategy for improving lamb survival depending on the current size of lambing mobs. However, it is difficult to provide generic recommendations to producers for the optimum mob size of ewes and value of paddock subdivision because these are dependent on enterprise-specific factors.

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.

A survey of the pasture productivity settings, practices and attitudes was undertaken for 229 pastoral producers who volunteered to enter the Triple P Program in 1997, and for 89 pastoral producers from 2 representative districts of Victoria. The latter group of producers was considered to be representative of the general population of pastoral producers in the regions where the Triple P Program was undertaken. Comparison of the survey results reveals that the volunteer participants entering the paired-paddock extension program employed different management practices and had different attitudes to productivity issues compared with the general pastoral producers. Before entering the program the Triple P volunteers were already employing more productive practices such as soil testing, measuring pasture availability and spring lambing. In addition the volunteers had higher whole-farm stocking rates and fertiliser use than the general pastoral producers. The different management practices employed by the 2 groups were consistent with their contrasting attitudes towards managing their farms. The Triple P volunteers were focussed on improving production per hectare through increased stocking rates, which could be achieved by additional expenditure on fertiliser and pasture renovation. The general pastoral producers were more focussed on improving production per head which was achieved by gauging animal performance, maintaining stock in good condition and maintaining expenditure on animal health. We contend that the differences identified between the producers volunteering to participate in the Triple P Program and the general pastoral producers are a direct consequence of the voluntary approach used to recruit Triple P participants. This approach attracts a select group of farmers who are inclined to engage in extension and training activities and tend to have different attitudes and practices to the general pastoral producer. A more proactive approach to recruitment will be required if a larger proportion of the general producer population is to engage in the paired-paddock extension program.

A checklist was developed to determine the extent to which different adult learning principles were embodied in the paired-paddock model used in the Triple P Program. A total of 181 producers that were involved in the Triple P Program between 1997 and 1999 completed the checklist at the end of the program. This enabled the relative strengths and weaknesses of the paired-paddock model from an adult learning perspective to be identified. The 15 adult learning principles assessed in the checklist were all operating in the paired-paddock model to varying degrees. The adult learning principles relating to the learning environment and learning process received the highest ratings from producers. In addition, the ratings given for these adult learning experiences were significantly correlated with the change index, a measure of the degree of on-farm adoption of productive pastures by the program participants. The principles relating to the learning environment were the existence of a comfortable learning environment, which allowed effective 2-way communication enabling participants to learn from each other. Principles relating to the learning process were the active participation of producers in activities, the use of knowledge and experience within the group, and the provision of opportunity for reinforcement of information and practice of skills. The relative weaknesses identified in the paired-paddock model from an adult learning perspective were the degree of self-directed learning done by participants, the limited involvement of participants in planning their learning experience, and the limited extent to which the program related to problem issues among the group. Despite these relative weaknesses it was concluded that the paired-paddock model embodies sound adult learning principles that assist in the delivery of quality learning outcomes for participants.

A detailed study was undertaken on the pasture management practices of 146 producers across south-east Australia who participated in the Grassland’s Productivity Program (GPP) for 3 years between 1993 and 1997. The GPP was an extension program to assist wool producers to develop skills and gain confidence in their ability to manage more productive pastures on their farms. The program consisted of 50 farmer groups (200 farmers participating) spread across the 4 states of South Australia, southern New South Wales, Victoria and Tasmania. Each farmer established paired-paddocks on their own property to compare productive pastures with existing pastures. Productive pastures involve increased rates of fertiliser on pastures containing productive species, with stocking rate adjusted to consume available pasture. After 3 years of involvement in the GPP, there was a whole-farm increase in P fertiliser use by 6.3 kg P/ha, stocking rates by 2.6 dse/ha and annual pasture resowing by 0.9% of the farm, when averaged across the 146 participants. The participants were applying the productive pasture technology to almost a third of their properties in 1997 and the intention was to increase this to over half of their properties by 2000. The participants also changed farm management practices as the program effectively developed management skills. There were increases in the ability to assess pasture quality and quantity, livestock by weighing or physical assessment, and the ability to calculate per hectare production and per hectare gross margins. A high proportion of GPP participants were soil testing (0.92) and spring lambing (0.72) at the completion of the program. The results indicated that the adoption of productive pastures was generally consistent across south-east Australia for pastoral producers who participated in this program, although south-west Victorian and south-east South Australian GPP participants did increase whole-farm P application by more than GPP participants from outside that region. The widespread change in farming practice was attributed to the additive and interactive effect of the paired-paddock comparison, the guidance provided by the facilitator, the group interaction and the skills training. Each of these components of the paired-paddock model combined to form an effective agent for change to increase pasture productivity on these grazing properties.

A survey of 146 pastoral producers across south-eastern Australia was conducted after they had participated for 3 years in the Grassland’s Productivity Program. The exit survey, together with earlier surveys, enabled the changes in whole-farm stocking rate and phosphorus fertiliser use, management practices, and perceptions of the Grassland’s Productivity Program, to be determined. The magnitude of the increases in productivity settings and the increased use of most recommended management practices were not influenced by either the facilitator who guided the groups of participants, or by the annual rainfall for the farm, which varied between 400 and 1000 mm. Path analysis of the survey data found that changes in productivity settings during 1993–97 did not depend on any one feature of the extension program. Rather the changes resulted from a hierarchy of interacting effects including certain initial (1993) and final (1997) management practices, attitudes to the program and perceived benefits from the program, and situational constraints such as the availability of suitable soil types on the farm. There were differences in the significant terms in the regression models that predicted the change in stocking rate, the change in fertiliser rate, or the combined variable for both, that was designated as the change index.

Summary. Nineteen participants in the Grassland’s Productivity Program were surveyed in autumn 1997 to determine whether they had continued to adopt productive pasture practices during the final 18 months of the program. The objective was to determine whether changes in commodity prices in 1996, involving falls in wool and beef prices and increases in prime lamb prices, and unfavourable seasonal conditions, impacted on the continuing adoption of productive pastures by participants of the Grassland’s Productivity Program. Despite the less favourable market and seasonal conditions, the Grassland’s Productivity Program participants continued to increase their adoption of productive pastures, almost trebling the area of land under the productive pasture technology from mid 1995 to 1997. This was achieved by rationalising farm expenditure in ways to cope with the less favourable conditions. The first was to undertake more pasture manipulation instead of high-cost pasture renovation. The second was to maintain expenditure on phosphorus fertiliser but focusing the application on more productive pasture paddocks. As a result the stocking rate across the whole farm was only increased marginally (by 0.2 dse/ha) from 1995 to 1997. Nevertheless the participants predicted that they would increase their stocking rate by an average of 17% across their farms, from 10.9 to 12.7 dse/ha, by the year 2000. The continuing strong commitment to adopt productive pastures is highlighted by the future intention of over half of the Grassland’s Productivity Program participants (53%) to implement the technology over their whole farm. The remaining participants intended to have at least half their farm under productive pastures. There was no discernible difference between wool growers and prime lamb producers in achieving adoption intentions apart from the area of the farm that is sown to productive species. This indicates that a short-term change in enterprise profitability is not necessarily a major determinant of adoption of more intensive grazing practices by participants in this type of group-facilitated program.

Summary. A detailed survey was undertaken in the spring of 1995 with 20 wool producers in south-west Victoria and the south-east of South Australia to determine the impact of their participation for 18 months in a program called the Grassland’s Productivity Program. This program involved groups of producers establishing paired-paddock comparisons on their own farms with guidance from an experienced facilitator. Productive pasture practices (increased fertiliser rates, responsive pasture species and high stocking rates) were used in one paddock, while the remaining paddock was managed with existing practices. A second group of 15 producers from the same districts who did not participate in the Grassland’s Productivity Program were selected at random and also surveyed. Although the 2 groups of producers had similar pasture productivity parameters (phosphorus fertiliser, stocking rates and pasture resowing rates) in the autumn of 1993, the Grassland’s Productivity Program participants had significantly (P