Page 12 - Hooked on Herefords Feb 2021

Announcement of the updated Technical

NZ Hereford Indexes

As we have been announcing over the past year, including for commercial breeders. So, as breeders you need to be
bulk emails sent late December and at the beginning aware of the changes to the indexes and the reasons why.
of this month, the Technical Committee and Animal
Genetics and Breeding Unit (AGBU) have been working for What are Selection Indexes?
numerous years on updating the NZ Herefords Indexes. Like breeding values (EBVs), Selection Index technology
The reason we were required to update the indexes is as is a well-established, science-based methodology that is
follows: used in many livestock species around the world. Selection
• The NZ indexes were last reviewed in 2016, since then Indexes provide an overall “score” of an animal’s genetic
costs and incomes have changed which effects the value for profit for a specific production system and are
short-term profit generated by a bull and longer-term calculated based on weightings placed on individual
profit generated by his daughters traits that are deemed to be important for that production
• The software package to generate the indexes is system. As such, Selection Indexes account for both sides
called BreeObject. The BreedObject technology has of the profit equation (costs as well as income), and also
recently been updated to version 6 reflect both the short-term profit generated by a bull
• By changing the software versions from BreedObject through the sale of his progeny, and the longer-term profit
4 to BreedObject 6, the current index values and generated by his daughters if they are retained in the herd.
rankings would change even if we didn't revaluate the
indexes Best Practice Guide to Using Selection Indexes
The article explains what the indexes are, why and Incorporating Selection Index information into selection
how they are updated and finally describes the new 3 decisions takes all the hard work out of trying to decide
indexes which have been selected. Whilst working on how much emphasis you need to put on individual EBVs
the new indexes, the varying markets for bulls, was given when determining which animals, you want to retain in
much consideration. The Technical Committee finally your herd or purchase. The recommended strategy for
identified three markets which they believe best meet the selecting animals is to complete the following steps:
requirements. While they acknowledge there may be other
markets, it’s believed that the majority of bulls would be i. Identify the Selection Index of most relevance to
able to fit in one of the three selected indexes. your or your clients breeding objectives. This decision
As you will be aware, selection indexes were not should be aided by the index descriptions available in
designed to be a tool for stud breeders to be basing the Help Centre on the BREEDPLAN website.
their selection on, (you should be looking at individual ii. Rank animals on the Selection Index. This can be done
EBVs as opposed to Indexes) however it is a viable tool easily from the NZ Herefords website from accessing

12 | NZ Herefords Newsletter. February, 2021 Hooked on Herefords