Lambing in a late break
Breeding ewe nutrition underpins productivity and profitability; her body condition affects her physical and genetic ability to utilise pasture and efficiently convert the feed resource, reproduction levels and lamb survival, and her and her progeny’s lifetime wool production.
Lambing in lower rainfall environments is usually planned so there is a good chance that ewes are lambing onto new season pastures at the end of autumn/early winter, and lambs can grow out for as long as possible on green feed into spring months before pastures mature and the season cuts off.
Often during late autumn, feed availability is low and of low quality. Ewes in late pregnancy need feeding in the paddock or containment to meet the rising demand for nutrition and to spell paddocks, protecting groundcover and allowing pastures to grow. Nutrition at this stage is important for udder development and colostrum quality and quantity, and the foetal lamb gains most of its body weight and lays down brown fat that is critical for survival. Once lambs are born, nutritional needs keep rising in early lactation, so maintaining consistent, good quality feed to meet requirements is important.
When the season break arrives late in May or June, pastures will germinate but feeding will need to continue for several weeks. Green pick will be sparse and full of water at a time when ewes need to be released from containment ahead of lambing.
Lambing in confined areas (2-5m2 per ewe) is not recommended because of privacy and mismothering issues, and health risks to the newborn lamb from manure and mud. However, with a late break and no feed wedge yet, moving ewes to another larger confined area such as some fenced off scrub or small sacrifice paddock will give ewes more space, and still bare but fresh ground for lambing. Mob size rather than stocking density will be more important for twin-bearing mobs, but if they can’t be split into many small mobs then allocate them the larger lambing paddocks, and the single-bearing mobs to smaller paddocks.
To avoid a wool break, let ewes adjust to their new surrounds at least 10-14 days before lambing begins and establish a feeding routine. Keep feeding ewes with the same feed ration fed in containment, using the same feeders to keep familiarity and avoid a change in diet. Use centrally placed trough feeders (20cm double sided trough/lambing ewe) to reduce shy feeders, and so recently lambed ewes can keep an eye on their lambs and return to the birth site. Feeding regularly and keeping disturbance to a minimum will help keep ewes calmer and avoid rushing so much when being fed. Self-feeders (5cm access/lambing ewe) require less labour and cause less disturbance, but it is harder to regulate what ewes eat. There can be more mismothering when ewes and lambs congregate around self-feeders making pirating easier, or there’s confusion when lambs try to find their mothers before they’ve properly bonded, and don’t follow their mothers away and die near the feeder.
To know you’re hitting nutrition targets, conduct feed tests on ration components as they can vary greatly in quality, particularly older 2022 hay. Cereal hay alone supplies only enough nutrition for maintenance, and will not be adequate for pregnant or lactating ewes – they need more
Concentrate on meeting rising energy needs based on ewe standard reference weight and pregnancy status; feeding enough to hold condition and making sure you don’t end up with underfed twins and overfed single bearing ewes at lambing, and they’re all set to cope with the energy peak demand at 30 days lactation.
Protein needs also go up as the foetus grows and the ewe begins lactating to produce high quality milk to support lamb survival and growth. Protein is sometimes underdone on straw or low-quality hay/barley rations, so target the higher protein level for each status in the table below. The ration needs to change every 10 days to meet those rising requirements, and lower condition ewes can be drafted and fed more.
(Source: NRC, 2007)
Note: Ewes carrying twins in pregnancy and lactation will have a 15% higher energy requirement than single bearing ewes, and triplets even higher.
Supplying digestible fibre in a ration by way of high quality hay in a hay feeder increases milk fat, and means less grain is needed to satisfy nutrient needs and minimises wastage. However feeding a high fibre ration to twin-bearing ewes near the point of lambing can be problematic as foetuses start taking up more space and begin to affect the amount of hay the pregnant ewe can eat. To counteract the lower intake, lower the hay portion and increase more nutrient dense barley in the ration.
Calculate how much fibre the ewe can intake (maximise to avoid health issues), then work out what energy and protein you are getting from the fibre source and top any deficits up with the grain portion. Use the NSW DPI Drought Feed Calculator App to work out the most cost effective energy source, and ensure you’re hitting the protein target. Convert dry matter amounts of feed to ‘as fed’ amounts to account for feed moisture.
A useful resource for confinement feeding is the recent publication ‘A guide to confinement feeding sheep and cattle in NSW’.
The Victoria Drought Resilience Adoption and Innovation Hub is a state-wide collaboration of 10 organisations.
Led by the University of Melbourne and with headquarters at UM’s Dookie Campus, the Vic Hub is a Partnership between five farming organisations (Birchip Cropping Group, Food & Fibre Gippsland, Mallee Regional Innovation Centre, Riverine Plains and Southern Farming Systems), four universities (UM, Deakin, Federation and La Trobe), and the State Government (through Agriculture Victoria).
One of eight hubs established nationally under the Australian Government’s Future Drought Fund (FDF), the Vic Hub works to enhance the drought preparedness and resilience of Victoria’s agricultural industries, the environment and regional communities, encompassing broader agricultural innovation. Engaging with a range of industry and community stakeholders, the Vic Hub links research with community needs for sustainable outcomes.
