Overview

The Multiple EndUses feature allows you to target different markets within your breeding program, typically controlled via an index per market while maintaining overall diversity.

In addition to matings targeted at long-term nucleus gains, you might want to make matings to give progeny that are targeted towards other uses/markets/customers/outcomes such as:

• To target the production of seedstock for sale to a range of customers with differing needs: eg.
  • Terminal versus maternal bulls
  • Target specific environments e.g. drought prone vs tropical (GxE)
  • A specific disease important to some but not to others
  • High versus low demand for marbling in the carcass
  • Targeting a specific set of novel traits e.g. low methane emission
  • Targeting a specific set of ‘trait leaders’ in dairy cattle.
• To contribute to a multiplier tier(s), possibly with a different breeding objective(s)
• To make resources for specific testing in some way – e.g. high versus low EBV groups for a specific trait, or balancing experimental treatments for relationships and/or trait merit.
• To prepare for a likely splitting of the breeding population into separate lines, each with their own trait profile and each to be diversity-managed independently.
• Development of sire and dam lines for eventual crossing, to exploit trait complementarity and possibly heterosis.
• To set up a Genomic Reference population that is diverse yet highly related to the target population for gEBVs.

Generally, you will want to use the best stock for the nucleus (most suited to the nucleus objective). And genetic diversity will generally be important only in the nucleus (although you will have the option to manage diversity in different parts of your population(s)). So, in some ways, this is all about targeting the head of the breeding program at the nucleus, and the tail of the program somewhat towards diverse customer needs. See Kinghorn et al. (2015) for an example.