Feed Affects the Meat/Wool Tradeoff

Summary

The project defined the magnitude of the effect of feed supply on the drain that wool imposes on energy available for reproduction.  This enabled sheep breeding advisors to assess whether breeding goals for meat + wool are achievable in specific feed environments.  More immediately, this project provided information to the forth-coming MLA / Australian Wool Innovation (AWI) workshop on the impact of nutrition on appropriate breeding objectives for specific production environments.  
We used sheep from the DAWA GSARI base flocks with defined Estimated Breeding Values (EBVs) for high or low clean fleece weight and CVfd, balancing the groups as far as possible for liveweight and fibre diameter.  Metabolic energy reserves (fat) and available energy (glucose concentration) were measured when the sheep are on low and then on high nutrition.  The results defined the extent to which the metabolic drain by a high genetic value for fleece weight can be ameliorated through better feeding regimes.