Key monitoring times for the ewe flock

Page last updated: Friday, 17 March 2017 - 8:10am

Please note: This content may be out of date and is currently under review.

To ensure sheep are in the right condition at the right time, they should be frequently monitored and their nutrition adjusted throughout the year. Frequent monitoring is especially important at times of drought, or at the change of season when paddock condition can change rapidly.

The seven step reproductive cycle

There are seven important phases in the reproductive cycle of Merino ewes. The lifetimewool project has quantified the impact of nutrition on the production of the ewe and lamb in each of these phases. The cycle starts at joining (day 0), proceeds through lambing (day 150) and weaning (day 240), and finishes with the pre-joining management of ewes.

Management of ewe condition during each step of the cycle affects:

  • conception success, reproductive rate, placental development, udder development and colostrum production of the ewe
  • foetal growth of the lamb, including wool follicle development which influences wool production in the progeny
  • ewe milk production, which influences lamb growth after birth.

At joining is ovulation, conception & placental development. Follicle development starts after day 30 into lambing. Foetal growth from day 90 into lambing. Over lambing is udder development. After lambing is follicle maturation & lamb growth into weaning

The five key times to monitor ewe condition and health

These five key monitoring points cover the times when sheep are most likely to be in the yards, and also allow adequate time to address the flock’s nutrition before any impact is permanent.

Table 1 Five key monitoring times for ewe condition and health
Phase Time (in days)


Day –60 from joining

Rams in (optional)

Day –60 from joining

Rams out  

Day 0

Pregnancy scanning  

Day 90 from joining


Day 120 from joining


12 weeks from start of lambing

Condition score and nutritional performance

Condition score is the most useful method of gauging the flock’s nutritional status and hence, performance. Assess between 25 and 50 sheep from the middle of the mob, or a random selection from each raceful.  

Keep a written record of their condition or plot it on a chart like the one shown below to develop a condition score profile for that mob of ewes.

Keep a written record of condition score throughout the ewe's year. Plot the condition score along a timeline.
Figure 2 Condition score of cycling ewes

Ewe mortality rapidly increases when ewes are under condition score 2 and lamb mortality rapidly increases when their mothers are under score 2.5 during pregnancy.

Aim to have ewes around condition score 3 during joining and lambing, with twinning ewes increasing their condition score over late pregnancy to condition score 3.3.


Mandy Curnow