Without knowing these parameters, a producer might spend years trying to "breed" for a trait that is actually 90% determined by the quality of the pasture. By focusing on and using Estimated Breeding Values (EBVs) , you can: Increase the average weight of lambs at market. Improve the uniformity and micron of wool clips.
Traits rarely move in isolation. When you select for one, you often get a change in another—sometimes for the better, sometimes not. Genetic Parameters for Sheep Production Traits
Heritability measures how much of the variation in a trait is due to genetics rather than environment (feed, weather, management). Without knowing these parameters, a producer might spend
Enhance the overall "efficiency" of the flock—producing more output with the same input. Traits rarely move in isolation
In some breeds, selecting heavily for increased fleece weight can lead to a slight decrease in fiber fineness.
Reproductive traits like twinning rates or lamb survival. Because these are heavily influenced by environment/management, progress through breeding is slow. 2. Genetic Correlations: The "Package Deal"
Traits like carcass lean meat yield and fiber diameter. You can make rapid progress just by selecting the best-performing individuals.