Page 11 - Merchiston Angus Catalogue ebook

INDEX DESCRIPTIONS Angus Pure Index (API) EBVs EXPLAINED

New Zealand Angus AngusPure Index - Predicted Response
The following three graphs reflects the relative change if the
New Zealand Angus Published Sires (at the Mid-August 2020 Heritability Estimates
TransTasman Angus Cattle Evaluation) were ranked on this
selection index and the top 10% were used within a breeding
program. Given that the Published Sires are the sires of the Expected Change in Individual Traits Calving Ease Dir 14% 86%
next generation(s) of New Zealand Angus cattle and have Gestation Length 65% 35%
more highly accurate EBVs (due to having progeny) than the Birth Wt 32% 68%
average animal in the database, these graphs represent the 200-Day Wt 12% 88%
approximate selection response one would expect to see in the 400-Day Wt 23% 77%
breed from using this index. CEd CEm GL BW 200W 400W 600W MCW Milk SS DC Cwt EMA Rib Rump RBY IMF
600-Day Wt 35% 65%
Above the 0 line (X axis) selects for more positive numbers and below Mature Cow Wt 40% 60%
Self Replacing Index (SRI) the line selects for more negative numbers. For some traits Milk 10% 90%
(e.g. growth), a positive response is desirable and for others
New Zealand Angus Self-Replacing Index - Predicted Response (e.g. days to calving), a negative response is desirable. Scrotal Size 39% 61%
Days to Calving 7% 93% 41% 59%
Expected Change in Individual Traits average over time develop a cow herd with the following: Eye Muscle Area 32% 68% 45% 55%
Carcass Wt
Genetic Selection of bulls using only the API tool will on
34% 66%
Rib Fat
•
Improved weaning rate through increased fertility and
easier calving
Rump Fat
•
Retail Beef Yield %
Progeny will be prime at heavy carcase weights where the
• A slowly increasing cow weight/size, and milk production Intra-muscular Fat % 32% 68% 60% 40%
CEd CEm GL BW 200W 400W 600W MCW Milk SS DC Cwt EMA Rib Rump RBY IMF improved marbling and subsequent eating quality traits The amount of genetic The amount of environmental
can be expressed
influence in a trait. (non-genetic) influence in a trait.
Above the 0 line (X axis) selects for more positive numbers and below
the line selects for more negative numbers. For some traits These characteristics are ideal for an environment where the
(e.g. growth), a positive response is desirable and for others
(e.g. days to calving), a negative response is desirable. cow herd can be managed with extra feed if seasonal feed May 2021 – Percentile Band for all 2019 born animals
deficits occur.
May 2021 TransTasman Angus Cattle Evaluation - Percentile Bands for all 2019 born animals
Use this table as a guide to compare individual animals with the current genetic level of the breed
Genetic Selection of bulls using only the SRI tool will on Calv-Ease Birth Growth Fert Carcase Indexes Extra
average over time develop a cow herd with the following: Checking individual EBVs relevant to your herd is advised. Dir Dtrs GL Bwt 200 400 600 Mwt Milk SS DC Cwt EMA Rib P8 RBY IMF SR AP HDT Doc
• Improved weaning rate through increased fertility and % days kg cm days kg sq.cm mm % $ %
easier calving Comparison of SRI and API High 1% +12.1 +10.7 -10.3 +0.1 +65 +115 +153 +150 +27 +4.2 -9.5 +89 +12.2 +3.3 +3.4 +2.7 +4.4 +168 +214 +145 +32
High 5% +9.8 +8.7 -8.3 +1.4 +59 +105 +140 +132 +24 +3.4 -8.0 +81 +10.0 +2.2 +2.2 +2.0 +3.6 +146 +183 +135 +25
• A slowly decreasing cow size, milk and slowly increasing SRI is a maternal trait emphasised index. API is also a maternal High 10% +8.4 +7.5 -7.3 +2.1 +56 +100 +133 +123 +22 +3.0 -7.2 +76 +8.8 +1.7 +1.6 +1.6 +3.2 +135 +168 +129 +20
body condition driven index with added carcase trait emphasis. High 15% +7.3 +6.7 -6.7 +2.5 +54 +97 +128 +117 +21 +2.8 -6.7 +73 +8.1 +1.4 +1.3 +1.4 +2.9 +129 +157 +125 +18
• Progeny will be prime at a younger age for slaughter High 20% +6.5 +5.9 -6.2 +2.8 +53 +95 +125 +113 +20 +2.6 -6.2 +71 +7.5 +1.1 +1.0 +1.2 +2.7 +124 +148 +122 +16
API selected animals can produce more net profit per animal High 25% +5.7 +5.3 -5.8 +3.1 +52 +92 +122 +109 +19 +2.5 -5.8 +69 +7.0 +0.9 +0.7 +1.0 +2.5 +119 +141 +118 +14
These characteristics are ideal for an environment where through extra performance when feed is abundant. High 30% +5.0 +4.7 -5.5 +3.4 +50 +91 +119 +106 +18 +2.3 -5.5 +68 +6.6 +0.7 +0.5 +0.9 +2.3 +116 +134 +115 +12
the herd is exposed to prolonged seasonal feed deficits and Finished progeny can be taken to heavier weights with High 35% +4.3 +4.1 -5.2 +3.6 +49 +89 +117 +103 +18 +2.2 -5.2 +66 +6.3 +0.5 +0.3 +0.8 +2.1 +112 +127 +112 +11
feeding supplement is unlikely. increased likelihood of achieving marbling premiums. High 40% +3.7 +3.6 -4.9 +3.8 +48 +87 +114 +101 +17 +2.1 -4.9 +65 +6.0 +0.3 +0.2 +0.7 +2.0 +108 +120 +109 +9
High 45% +3.0 +3.0 -4.6 +4.0 +47 +86 +112 +98 +17 +2.0 -4.6 +63 +5.6 +0.2 +0.0 +0.5 +1.9 +105 +113 +106 +8

50% +2.3 +2.5 -4.3 +4.2 +47 +84 +110 +95 +16 +1.9 -4.3 +62 +5.3 +0.0 -0.2 +0.4 +1.7 +101 +105 +104 +6
SRI selected animals can produce more net profit per animal Low 45% +1.6 +1.9 -4.0 +4.4 +46 +83 +108 +93 +16 +1.8 -4.0 +60 +5.0 -0.1 -0.4 +0.3 +1.6 +97 +97 +101 +5
Checking individual EBV’s relevant to your herd is advised. through extra performance in environments where Low 40% +0.9 +1.3 -3.8 +4.6 +45 +81 +106 +90 +15 +1.7 -3.7 +59 +4.7 -0.3 -0.6 +0.2 +1.5 +93 +89 +98 +3
the cow herd is likely to be challenged by regular seasonal feed Low 35% +0.2 +0.7 -3.5 +4.8 +44 +80 +103 +88 +14 +1.6 -3.4 +57 +4.4 -0.4 -0.8 +0.1 +1.3 +90 +82 +95 +2
deficits, maintaining body condition is critical Low 30% -0.7 +0.1 -3.2 +5.0 +42 +78 +101 +85 +14 +1.5 -3.1 +55 +4.1 -0.6 -1.0 +0.0 +1.2 +86 +74 +92 +0
to longevity and feeding out is not a viable option. Low 25% -1.6 -0.7 -2.9 +5.3 +41 +76 +98 +81 +13 +1.3 -2.8 +53 +3.7 -0.8 -1.2 -0.2 +1.0 +81 +66 +88 -2
Low 20% -2.6 -1.5 -2.5 +5.6 +40 +73 +95 +78 +12 +1.2 -2.3 +50 +3.3 -1.0 -1.4 -0.3 +0.9 +76 +57 +84 -4
Low 15% -3.8 -2.5 -2.0 +5.9 +38 +71 +91 +74 +12 +1.0 -1.9 +47 +2.8 -1.2 -1.7 -0.5 +0.7 +70 +47 +80 -6
Low 10% -5.4 -3.9 -1.4 +6.3 +35 +67 +86 +68 +10 +0.8 -1.2 +43 +2.2 -1.5 -2.1 -0.8 +0.4 +63 +35 +74 -9
Checking individual bull EBVs to make sure the index
Low 5% -7.9 -5.8 -0.4 +6.9 +32 +62 +78 +59 +9 +0.4 -0.1 +36 +1.3 -2.0 -2.7 -1.2 +0.1 +54 +21 +65 -13
and the EBVs match your expectations are advised.
Low 1% -13.2 -9.6 +1.6 +8.2 +25 +51 +63 +42 +6 -0.3 +2.1 +26 -0.4 -3.0 -3.9 -2.0 -0.5 +27 -2 +44 -21
Using the flow chart may help you with your decisions.
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