Lamb survival initiative results for 2017
Rebecca Butcher, DPIRD, Moora, WA
Author correspondence: rebecca.butcher@dpird.wa.gov.au
This article presents the results of the 2017 Lamb Survival Initiative. This project is now complete. The results for 2015 and 2016 can be found in the March 2016 and September 2017 editions of the Ovine Observer, respectively.
Introduction
The Department of Primary Industry and Regional Development’s (DPIRD) Lamb Survival Initiative ran from 2015 to 2018 in conjunction with regional grower groups and private consultants. It was aimed at providing support to producers to increase lambs survival and achieve 100%+ marking rates. The initiative provided training and support and allowed producers to benchmark their marking rates against others in similar regions and state-wide.
In order to build producer confidence and skills to lift marking rates to 100%+ the initiative encourage producers to:
- undertake pregnancy scanning for multiples on a significant proportion of their adult ewes
- record and submit data on the reproductive rate, marking rate and weaning rate achieved in the scanned ewe flock/s so that the rates can be benchmarked against producers in similar regions
- attend at least one training course or workshop focused on reproduction
- work closely with industry professionals where reproduction rates are less than expected.
In the final year of the initiative (2017) three producer groups were involved, Facey Group (Woodanilling), Southern DIRT (Kojonup) and a private group based at Augusta. A total of 20 producers participated across the three groups. Lifetime Ewe Management accredited facilitators Ed Riggall and Jonathan England were selected by the groups to provide in depth information on reproduction.
Facilitators met either on-farm with each producer or organised group meetings to provide recommendations on farming practices such as condition scoring, feed budgeting and sheep husbandry.
Information collected around the reproductive cycle included:
- ewe condition score at rams out and pregnancy scanning
- scanning rate (number of lambs scanned per 100 ewes joined)
- marking rate (number of lambs marked per 100 ewes joined)
- weaning rate (number of lambs weaned per 100 ewes joined)
- weaning weights (where facilities available)
- feed on offer (FOO) at lambing and details of supplementary feeding.
Collection of this information has enabled producers to gain valuable understanding on where lambs were being lost throughout the reproductive cycle providing them with targeted ways to improve their lamb survival and marking percentage.
Ewe condition score
As shown in Figure 1, each of the groups maintained a high average condition score (CS) between rams out and pregnancy scanning. Condition score was slightly reduced at pregnancy scanning compared to at rams out at each site, however the loss in condition score was very small being less than 0.15. In previous years, condition score generally increased between rams out and pregnancy scanning however, these results reflect the late break and reduced FOO in 2017.
Feed availability
In 2017, FOO was moderate to low amongst the groups, ranging from 700-1200 kilograms/hectare (kg/ha), and generally lower than in 2016.
Figure 2 shows that in areas where paddock feed availability was higher; ewes were given less supplementary feed, the type of supplement used varied from hay, wheat seconds, oats, barley, an oat/barley mix and/or lupins. Higher rates of supplementary feed were allocated to feeding twin bearing ewes over singles.
Lifetime Wool recommendations are for lambing down ewes in a minimum of 1200kg of dry matter/hectare (DM/ha) for single bearing ewes and 1800kg DM/ha for twin bearing ewes. As this was not possible for most groups, supplementary feeding was critical. Lamb survival can be improved by 15-20% in twin bearing ewes where condition score is increased from 2.5 to 3 through careful management of nutrition (Lifetime Wool). This would result in an extra 30 lambs for every 100 ewes joined.
Reproductive rates
Reproductive rates included the number of lambs scanned, marked and weaned per 100 ewes joined (Figure 3). The Augusta group had the highest reproductive rates for scanning, weaning and marking. Each of the three groups had marking rates about 100%, achieving one of the main aims of the initiative.
As seen in previous years, the greatest lamb loss for each group occurred between pregnancy scanning and lamb marking and was higher in groups with higher scanning percentages. This mortality may be either in-utero, during the birthing process or in the first 72 hours of life, where it has been found that most lamb mortality occurs.
Despite a challenging year with low FOO, the losses between lamb marking and weaning were small, particularly for the Woodanilling and Augusta groups.
Weaning weight
While not all producers involved in the project recorded weights at weaning, the practice is becoming more prevalent than in previous years as producers practice precision farming. The average weaning weights were recorded with the results shown in Figure 4.
The difference between average weaning weight for the lowest and highest groups was almost 10kg. While Southern Dirt (Kojonup) had the highest average weaning weight for 2017, it was 7kg below the group’s average for 2016 due to the poor year.
There are many strategies that can be put in place to increase lamb survival including monitoring the condition score of ewes, scanning for multiples foetuses and preferentially feeding twin bearing ewes, as well as providing shelter, implementing a pest management program and limiting mob size at lambing.
Further information on increasing lamb survival can be found in the September 2016 edition of Ovine Observer or on the website.
If you would like to know more information from the results of the Lamb Survival Initiative, please contact Rebecca Butcher, Sheep Industry Development Officer, Moora on (08) 9651 0540 or rebecca.butcher@dpird.wa.gov.au.