Page 30 - NZ Herefords National Sale Catalogue ebook

THE BREEDOBJECT INDEX SYSTEM 3. It addresses the issues of prioritizing the economic
importance of EBVs and relationships between
Combines genetic information (EBVs) with financial traits, in the selection process.
information (costs and returns relating to a specific
production system) and brings these together into one Selection Indexes reflect both the short term profit
figure or Index (EBV for Profit), which is expressed in generated by a sire through the sale of his progeny, and
‘dollars per cow mated’. It has major advantages over the longer term profit generated by his daughters in a
selecting bulls using EBVs: self-replacing cow herd.
1. It is much more user friendly because it ranks bulls Standard Selection Indexes are now available for most
based on their profitability in a specified production breeds. The standard breed specific Selection Indexes
system. have been designed to cater for the commercial market
production systems of general relevance in each
2. It is expressed as ‘profit per cow mated’, whereas particular breed. These Selection Indexes are intended
most EBVs do not directly relate to profit. for use by both seedstock & commercial producers.

2021 HEREFORD GROUP BREEDPLAN EBV’S AVERAGES
Direct Dtrs GEST BW 200W 400W 600W MAT W
+2.1 +1.8 -0.5 +4.1 +33 +55 +78 +67
Milk SS DC CWT EMA RIB FAT RUMP RBY IMF
+17 +2.1 -2.9 +52 +3.6 +0.7 +0.8 +0.8 +0.5

Selection Indexes - NZ HEREFORDS
Hereford selection indexes are calculated for three Beef Heifer Index - Estimates the genetic differences
market specifications, namely, Hereford Prime, Beef between animals in net profitability per yearling heifer
Heifer, Dairy Beef. These Indexes relate to typical joined for a typical self-replacing commercial herd
commercial herds in New Zealand targeting these where Hereford bulls are joined to either Hereford or
specifications. other British breed heifers. Selected heifers are retained
for breeding and so maternal traits are of importance.
Index values are reported as EBVs, in units of relative Steers target 510 kg live weight (280 kg HSCW and 7
earning capacity ($’s) for a given market. They reflect mm P8 fat depth) and heifers 450 kg ( 250 kg HSCW and
both the short-term profit generated by a sire through 8 mm P8 fat depth) at 20 months of age.
the sale of his progeny, and the longer-term profit
generated by his daughters in a self-replacing cow
herd (where applicable). A selection index combines the Dairy Beef Index - Estimates the genetic differences
EBVs with economic information (costs and returns) for between animals in net profitability per mixed age
specific market and production systems to rank animals dairy cow joined with all progeny destined for slaughter.
based on relative profit values. Note that different types Steers and heifer progeny target 550 kg live weight (300
of animals can give similar profit values, so consideration kg carcase weight and 6 mm fat depth) at 24 months of
should be given to both the index and the component age and at 475 kg live weight (260 kg carcase weight
EBVs when selecting animals for a particular production and 7 mm fat depth) at 22 months, respectively.
system. More information is available on selecting
animals using a selection index. FINANCIAL IMPLICATIONS OF USING AN INDEX
The Index values are derived using BreedObject Two bulls, with Indexes of $0 and $50 are mated to
technology. More information is available from the genetically similar cows. Each bull mates 200 cows
BreedObject web site. during its lifetime. The second bull, with an Index of $50,
will generate $5000 ($50/2 X 200) more profit during his
Hereford Prime Index - Estimates the genetic differences lifetime than the first bull.
between animals in net profitability per mixed age cow
joined for a typical self-replacing commercial herd
where Hereford bulls are joined to either Hereford or
other British breed females and targeting the production SELECTION INDEX VALUES
of grass finished steers for the Hereford Prime program. HEREFORD PRIME BEEF HEIFER DAIRY BEEF
Selected heifers are retained for breeding and so
maternal traits are of importance. Steers target 550 kg +$111 +$112 +$105
live weight (300 kg carcase weight & 7 mm P8 fat) at
20 months of age, and heifers 475 kg (260 kg carcase
weight & 8 mm fat depth), at 22 months of age.
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