Feeding a Ewe Flock That Is Behind Condition at Day 115

Recommendation: do all three, in this order - cull the 45 thinnest ewes this week, transition the flock onto fodder beet, and buy baleage for the twin-bearing mobs.

Reasoning

• Late pregnancy is when the demand curve steepens. About 70% of foetal growth happens in the last 6-8 weeks, and a twin-bearing ewe's energy requirement rises to roughly 1.3-1.5 times maintenance. A set-stocked flock on 1,350 kg DM/ha and falling is being asked to do more on less.
• Culling first is the efficient move. The 45 ewes at BCS 1.5-1.8 with worn teeth are the least likely to rear a lamb and the most likely to cost money - pregnancy toxaemia, assisted lambings, or a dead ewe. Selling them realises about $4,950 and cuts demand immediately by roughly 45 ewes at about 1.5 kg DM/day, near 70 kg DM/day - several days of extra feed for the rest.
• Condition gain is achievable but tight. A mature Romney gains one BCS for roughly 5-6 kg liveweight, so 2.1 to 3.0 means about 5 kg over five weeks, roughly 1 kg/week. That is realistic only on genuinely good feed.
• Fodder beet supplies energy cheaply but is low in protein, needs a 7-10 day transition to avoid acidosis, and should not be the whole diet for twin-bearers, which need protein for udder development.
• Check the baleage maths before committing. 220 bales at ~200 kg DM is about 44,000 kg DM. Spread over 275 ewes for 42 days that is only about 3.8 kg DM/ewe/day, not the 8 kg assumed. Confirm bale weight and budget for more if twin mobs are to be fed properly; $20,900 is a large commitment on a low bank balance.

Priority: thin ewes out, twins fed best, singles maintained.

What it is

Pregnancy toxaemia (sleepy sickness) occurs when a ewe's energy demand outruns her feed intake in late pregnancy. She mobilises body fat, ketones build up in the blood, and the ewe becomes dull, separates from the mob, staggers, goes down and usually dies, often with lambs still inside her. It most commonly hits thin ewes carrying twins in the last 4-6 weeks, and is triggered by any stress that stops her eating - cold, wet weather, a yarding, shearing, dogging up, or a sudden feed change.

Why this flock is exposed

• Average BCS 2.1 at day 115 is well below the 3.0-3.5 target for twin-bearers.
• 60% of the flock is carrying twins, which is the highest-demand group.
• Pasture cover is low and falling, and the flock is set-stocked, so there is no ability to shift stock onto better feed quickly.
• The thinnest ewes at 1.5-1.8 are the ones with the least fat reserve to mobilise.

How the plan reduces risk

1. Culling the 45 thinnest removes the highest-risk animals entirely - they are the ones most likely to go down.
2. Fodder beet and baleage lift the energy supply and give the twin mobs a buffer when the weather turns.
3. Transitioning gradually onto beet avoids a sudden rumen upset, which is itself a trigger.
4. Mobbing and feeding twins separately means extra feed reaches the animals that need it, not the singles and drys.
5. Handling quietly and avoiding unnecessary yarding in the last month reduces the stress triggers. Any ewe found dull and off-feed should be treated immediately; a drench of propylene glycol and veterinary advice can save her, but prevention through condition is far cheaper than treatment.

Why fewer ewes can mean more lamb

Culling does reduce the number of ewes mated, but the 45 ewes in question are not producing much. A ewe at BCS 1.5-1.8 with worn teeth is likely to:

• ovulate and conceive late, or not at all;
• carry and rear a single rather than twins;
• produce a small lamb with poor survival, especially in bad weather;
• go down with pregnancy toxaemia, costing the ewe and both lambs.

Those ewes consume feed that has a far higher return elsewhere. Removing them frees roughly 70 kg DM/day for five weeks - around 2,500 kg DM - which goes to twin-bearing ewes that convert it into two lambs each. A twin-rearing ewe at BCS 3.0 will wean two lambs at 15-18 kg carcass weight; a thin single-rearing ewe may wean one lamb at 12 kg or nothing at all.

Crunching it roughly

• 45 ewes sold at $110 = about $4,950 cash in the hand, before lambing, when the bank balance is lowest.
• Feed saved supports higher survival and weaning weights across about 165 twin-bearing ewes. Lifting survival in that mob by even 5-8% is roughly 8-13 extra lambs - at $110-$150 a lamb store, that alone is $900-$2,000, before counting the ewes that would have died.
• Fewer ewes also means fewer assisted lambings, less labour at the busiest time and lower animal health costs.

The honest caveat: the arithmetic works because these particular ewes are genuinely low performers. Culling 45 ewes in average condition at BCS 2.8-3.0 would be a different calculation and would probably reduce output. The decision hinges on which animals go, not on the number.