Ultrasound pregnancy scanning (echography) of ewes is one of the most impactful management tools available to sheep farmers for both welfare and productivity. By identifying whether ewes are carrying singles, twins, triplets or are empty, producers can tailor nutrition during the critical last 6 weeks of pregnancy — the period of greatest foetal growth and highest metabolic demand on the ewe. Evidence consistently demonstrates that targeted nutritional management based on scanning results dramatically reduces metabolic disease, improves lamb birth weights, reduces perinatal lamb mortality, and prevents the suffering associated with pregnancy toxaemia.
Pregnancy toxaemia (twin lamb disease) is one of the most serious welfare problems in sheep farming. Ewes carrying multiple foetuses have the highest energy requirement but the most limited rumen capacity. Without scanning, producers cannot identify which ewes are at highest risk. The result: multiple-bearing ewes fed the same ration as singles may receive inadequate energy, falling into negative energy balance, mobilising body fat, and developing ketosis.
Studies show that scanning followed by appropriate feed grouping reduces pregnancy toxaemia incidence by 40–70% in high-risk flocks. Each prevented case represents significant suffering avoided.
Triplet and quad lambs identified by scanning can be managed appropriately at lambing — farmers can prepare fostering strategies, bottle-rearing supplies, and additional attention at lambing time. Without scanning, unexpected multiples are a leading cause of lamb abandonment (inadequate milk supply not anticipated) and perinatal mortality.
Empty ewes (approximately 3–8% of the flock in most systems) detected by scanning can be culled or managed separately at maintenance nutrition, preventing wasted resources and allowing appropriate welfare-based decisions.
Optimal scanning window is day 50–90 of gestation (earlier than 45 days reduces accuracy; later than 100 days makes litter size determination more difficult):
Standard scanning groups allow targeted nutritional management:
Body condition score at scanning should inform feed allocation alongside litter number — thin ewes carrying multiples are the highest priority group for welfare intervention.
The return on scanning investment is consistently positive: