The most important target for ewe flocks is to regain condition lost in early pregnancy before lambing commences.  Meeting this target gives the optimum profitability. An alternative option is to start at a higher condition score, lose 0.6 of a condition score and re-gain at least 0.3 of the condition lost by lambing.

There is a trade-off between the saving on feed in early pregnancy (lose more condition) and loss of production, particularly lamb survival and ewe wool production. As ewe condition approaches CS 2 both her and her lambs survival will be compromised.  Any breeding ewe be no lower than score 2 for this reason.

In late pregnancy green feed must be used to gain condition as supplementary feed costs are too high to offset any gains in production. Ewes require 1200 FOO (900 HM) by lambing for single ewes and 1800 FOO (1400 HM) for twinning ewes to regain lost condition. If this amount of green feed isn't likely to be available then the next best approach is to lose less condition or maintain ewe condition throughout pregnancy. Establishing pastures should be deferred so that FOO targets can be reached. The greatest value of supplementary feed is maintaining the ewe while pastures are being deferred to allow good pastures for lambing.

Key points:

• Incre asing ewe condition should only be done using green feed.  It is rarely economic to feed grain to increase condition
• Only lose enough condition over autumn that can be regained using green feed after the break. Defer pastures to achieve this level of feed.
• If ewes are, by reason of a good summer, on a higher starting CS, continue to follow the shape of the higher profiles rather than lose more condition to start on the lower profile.  This will still give a high economic return.        

Profitability of following the optimum pro f ile

Following the optimum profile of joining at CS 2.6, losing 0.3 of a condition score in early pregnancy until the break of season and regaining all lost condition on green feed gives the highest profitability for this region and system of $33.30/ewe (figure 2, profile 3).

Maintaining ewes at their joining condition throughout the whole of pregnancy is expensive, approximately $3.70/ewe compared to losing and regaining condition at CS 2.6 due to the extra hand feed over autumn and not taking advantage of the rapidly growing feed in spring(figure 2, profile 2).  Maintaining at a higher condition score such as CS 3 throughout pregnancy is -$6.80 less profitable than losing and regaining at CS 2.6 (profile 1.).