Ovine Observer

Lamb Survival Initiative

Katherine Davies, Department of Agriculture and Food, Western Australia (DAFWA), Northam

Just over 6 per cent of Western Australian (WA) Merino and sheep producers and 9% of dedicated prime lamb producers achieve marking rates of over 100%. This means that less than 500 producers in WA achieve 100%+ lamb marking in any given year.

The Lamb Survival Initiative, through involvement with regional grower groups, aims to provide support for producers to achieve 100%+ by providing training and support, encouraging  producers to set achievable targets and benchmarking their marking rates against others in similar regions and across the state.

In order to build producer confidence and skills to lift marking rates to 100%+ we encourage them 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 for benchmarking against other producers
• attend at least one training course or workshop which focuses on reproduction
• work closely with industry professional on issues with the reproduction rates of their flock.

Last year, 2015, was the first year of the Lamb Survival Initiative involving five grower groups spread throughout the southern region of WA. These groups included Facey Group (Wickepin), West Arthur Trials Group (Darkan), Southern DIRT (Kojonup), the Gillamii Centre (Cranbrook) and ASHEEP (Esperance), with a total of 33 grower participants.

Lifetime Ewe Management accredited facilitators Ed Riggall and Joe Young 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 go through issues such as condition scoring, feed budgeting and husbandry practices for increasing lamb survival. 

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 enabled producers to gain valuable understanding on where lambs were being lost throughout the reproductive cycle.

As shown in figure 1, ASHEEP maintained its average condition score (CS) between rams out and pregnancy scanning, while Gillamii Centre and Facey Group decreased very slightly and West Arthur and Southern DIRT increased very slightly.

Figure 1 Difference in condition score (CS) between rams out and pregnancy scanning in 2015

FOO was an issue in the Facey Group and West Arthur areas in 2015, with both Wickepin and Darkan receiving only decile 1 rainfall for the 2015 growing season. Figure 2 shows that in areas where paddock feed availability were low; ewes were supplemented with larger amounts of feed, mostly in the form of barley, lupins, hay and pellets. 

Figure 2 FOO and supplementary feeding amounts. Key: kilograms per hectare (kg/ha), grams per head per day (g/hd/day).

Reproductive rates included the number of lambs scanned, marked and weaned per 100 ewes joined (figure 3). You can see that the greatest lamb loss for each group occurred between pregnancy scanning and lamb marking. 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 80% of lamb mortality occurs. Please note that the West Arthur group had incomplete data for weaning, therefore the average weaning rate for the group is higher, but otherwise would have been expected to follow the same trend as the other groups.

Figure 3 Change in reproductive rates from pregnancy scanning to lamb marking and weaning. Note: West Arthur weaning data was incomplete

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 and limiting mob size at lambing.

Further information on increasing lamb survival can be found in the September 2015 edition of Ovine Observer or on the DAFWA website.

While not all producers involved in the project had access to scales, weaning weights were collected by many of the participants with the results shown in figure 4. 

Figure 4 Average weaning weight of lambs for 2015

Feedback from producers in the initiative indicated that further extension of information around weaner management as well as pasture production and management were highly desirable. In 2016, information will also be collected on the number of twins and singles conceived, marked and weaned in order to gain a greater understanding of lamb losses for single and twin born lambs.

If you would like to be involved in the 2016 season of the Lamb Survival Initiative, please contact Katherine Davies, Sheep Industry Development Officer, Northam on +61 (0)8 9690 2169 or katherine.davies@agric.wa.gov.au.