Page 51 - NZ Herefords Magazine 2019 Edition

Industry Focus

Beef Progeny Test

turns spotlight onto

structural assessment

WORDS / PHOTOGRAPHS BEEF + LAMB NZ GENETICS

THE BEEF + LAMB NEW ZEALAND (B+LNZ) Genetics Beef BEEF CLASS STRUCTURAL TRAITS SIRE
Progeny Test (BPT) compares bulls under New Zealand DEVIATIONS FROM IDEAL
commercial farming conditions. It includes a project assessing
the performance of sires for structural soundness. BEEF CLASS STRUCTURAL TRAIT MIN MAX MEAN SD

HOW THE PROGENY TEST WORKS Rear Legs Hind View 0.594 1.134 0.847 0.106
Now in its fifth year, the test involves mating more than 3000 Front Feet Angle 0.624 1.061 0.834 0.093
cows and heifers annually across four large stations and one Front Feet Claw Set 0.611 0.974 0.787 0.063
dairy farm. Dairy-born calves are assessed for calving ease, while
beef-born steers are assessed on their finishing performance Rear Legs Side View 0.549 0.848 0.714 0.052
and carcass traits. Replacement heifers are tracked for their Rear Feet Angle 0.627 0.832 0.718 0.038
maternal characteristics. Front Legs Front View 0.398 0.612 0.536 0.035
A mix of both internationally sourced and New Zealand
semen is used from more than 10 breeds. Specific bulls are Rear Feet Claw Set 0.064 0.112 0.087 0.009
included to provide genetic links to international programmes,
where carcass data is being collected. NEXT STAGE OF THE TEST
Over time, the test will: B+LNZ Genetics will look at the economic cost of unsound
• Evaluate maternal performance and survival for different structure on production and cow longevity. EBVs could then
cow types in commercial conditions. be developed for more effective genetic gain in structural
• Generate potential new EBVs for cow performance – e.g. soundness.
heifer puberty, cow condition score and cow stayability. Australian data shows that the structural traits found to be
• Evaluate the relationship between maternal performance, problematic in the B+LNZ Genetics Beef Progeny Test are 30 to 50%
finishing performance and carcass quality/market attributes. heritable. Angus Australia publish five structural EBVs and breeders
• Evaluate across breeds. can submit data by using a Beef Class accredited assessor.
If you are a breeder collecting this data already, then it can
STRUCTURAL ASSESSMENT SPOTLIGHT be submitted to BREEDPLAN and stored until a time when
The 1027 calves from Cohort 1 were structurally assessed at 14 EBVs are available.
to 16 months old, using the Beef Class Structural Assessment
system. The progeny test was looking for variation in structure HEREFORD SIRES WELL REPRESENTED
to see: To date the B+LNZ Genetics Beef Progeny Test programme has
• if a trait was problematic; accepted 97 Hereford sires – nearly 40% of the 254 sires used
• how much variation existed between sires, to see if the trait across the 10,123 total cow matings and resulting 7086 calves.
was under genetic control, and Most Hereford sires nominated by breeders have been
• whether overseas genetics were different from local genetics. accepted, representing a true and broad cross section of New
The Beef Class Structural Assessment System was used to Zealand’s Hereford gene pool. The progeny test is an important
assess the sires. Traits were assigned a score of 1 to 9, with a data resource for research and EBV prediction for New Zealand
score of 5 generally considered ideal. The table above shows Hereford breeders, because the test’s data informs BREEDPLAN.
how much the traits deviated from ideal. For example, for Rear All Cohort 1 steers have been processed and sires’ results
Legs Hind View the sires’ calves were on average 0.8 of a score for all traits are now available on the B+LNZ Genetics website.
away from ideal and at the most 1.1 of a score away from ideal. Nearly 400 white-faced steers have each had 25 individual
Across the cohort assessment, the most problematic traits measurements taken – informing their 11 sires for genetic
were: evaluation. Cohort 2 sires and progeny will soon have results
• Rear Legs Hind View (often tending cow hocked/6s); available on growth, carcass, and structural assessment.
• Front Feet Angle (often tending low angle/6s), and Key ongoing female measurements are still being collected and
• Front Feet Claw Set (often tending scissor/6s). will take many years to be fully reported on. Sires’ daughters from
These same structural traits also tended to be genetic – i.e. Cohort 1 at Mendip Hills Station have now produced three calves
associated with the bull. and have had reproduction data collected from four matings.

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