Ewe NutritionWhile wool growth requires very little energy (40-50 MJME/kg of wool), the nutritional management of ewes will have major changes on fleece yield and wool characteristics:
- Underfeeding reduces the fibre output from wool follicles resulting in finer, shorter wool
- Generous feeding levels support longer, coarser and heavier fibres
- Sudden changes in amount or quality of feed can reduce staple strength and fleece yield.
In the ‘ideal world’, a wool follicle needs the same nutrients delivered consistently all day, every day. A ewe’s world is less than ideal – continual changes in amount and quality of feed, combined with stresses of pregnancy and lactation change wool follicle nutrition and cause narrowing of the fibre.
Diet risks for wool fibre tenderness include underfeeding and changes of diet between pasture and forage crops, or from poor to high quality pastures. Stress associated with pregnancy and lambing amplifies the effects of poor nutrition on wool.
Feed budget – underfeeding remains the most likely cause of light-conditioned ewes and reduced fleece yield and quality.
Consistency of feeding and minimising changes in body condition is the key
Compare pasture growth rates and forage crop yields against the feed demands of ewes and other stock classes on both an annual and seasonal basis. Look for opportunities to increase pasture and forage crop growth rates by reviewing soil fertility and nitrogen use. Also, consider re-grassing with higher yielding modern pasture species.
Feed for improved ewe body condition
To gain an extra 0.5 body condition score (BCS), ewes need to consume an extra 20 kg of dry matter over and above other demands for maintenance, growth, pregnancy and lactation. Ewes that gain BCS will increase fleece yield.
Sudden changes in diet
Abrupt changes of diet from pasture to forage crops or change from summer stalky pasture to lush autumn regrowth can reduce staple strength. More gradual adaptation of the ewe’s rumen to a new feed and/or offering hay or baleage when changing diets can reduce risk of wool break.