Body condition scoring ewes at least six weeks out from mating can make a significant difference to conception rates and scanning percentages.
Research has shown that lambing percentages increase by 6–10% for every extra unit of body condition score at mating. The flushing effect may provide an additional 5–10%.
Ideally, ewes should be going to the ram at a body condition score (BCS) of between 3 and 4 and it is the percentage of the ewe flock with a BCS of below 3 at mating and lambing that is the single most important factor influencing the profitability of an ewe flock.
The biggest percentage jump in scanning percentage will come from reducing the number of poor condition ewes at mating, it is these poor condition ewes that will bring down the overall performance of the flock.
Pre-mating management
By preferentially feeding ewes that have a BCS below three (they may require supplementary feed) in the lead up to mating, their body condition and lambing percentage can be improved.
It is also recommended that a faecal egg count is carried out on these low condition score ewes as they may require a drench.
Ewes need 1.0-1.3 kg DM/head/day of average to good quality feed just to hold body condition during mating and early pregnancy.
Ideally, the ewe mob should be rotated rapidly on to pasture that is 5–6 cm height. Grazing below 3cm or 1500 kg DM/ha will result in loss of body condition and lower lambing rates.
Body condition scoring ewes has been found to be a driver of profitability in top performing sheep flocks. The three best times to BCS are pre-mating, scanning and weaning.