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EBLEX Better Returns Programme
Genetic Improvement
of Beef Cattle in the UK
Material produced for EBLEX Beef BRP
by Signet Breeding Services
Presentation Outline
 Background
 Importance of Performance Recording
 Using EBVs and Indexes
 Results of using EBVs and Indexes
 Summary
Genetic Improvement - Historical
Perspective
Natural selection + deliberate animal breeding
= great variety of breeds in the UK
‘Master breeders’ e.g.
Robert Bakewell (1725 - 95)
Shire horses, Longhorn cattle
and Leicester sheep
“Prize Livestock at Dishley Grange”
Thomas Weaver 1802
Assessing performance


?

Within-Breed Selection
Selection of the best animals within a pure
breed
Only a small proportion of the beef cattle
population of Britain are purebred but they
are pivotal in the success of any breed
substitution or cross-breeding programmes
(the methods just explained) and therefore
vital for the genetic improvement of beef
cattle in the UK
Performance Recording
Performance Recording
 The analysis of physical performance records of
individual animals
 Results then used to assist decisions when
selecting breeding stock
Performance recording
The major difficulty to overcome:
How much of an animal’s performance is due
to it’s genes and how much is because of the
environment in which it is reared, managed
etc?
Performance recording
Health
Birth & Rearing Type
Year / Season
Age of Animal
Farm factors
eg mineral status
Age of Dam
Nutrition
Inherited Genetic
Potential
Performance recording
Which is the best bull?
….it is the same animal
but on a very different
amount of feeding!
Performance recording
Why is this important?
 Selection ‘by eye’ can lead to the wrong breeding
decisions.
 Environment can mask poor performance
 Not all traits are visible e.g. gestation length etc
 Selecting for one trait can be to the detriment of another
e.g. increased muscling and calving ease. A method of
monitoring change is therefore required.
 The effects of breeding decisions can last in the herd for a
very long time
Performance recording – BLUP
BLUP: Best Linear Unbiased Predictor
 statistical procedure used in the UK dairy industry since
early 1970s
 disentangles genetic and non-genetic effects on
performance
 genetic links between herds required for across herd
analysis (AI)
 compares related animals with their contemporaries across
many different herds using related animals as a benchmark
HERD 2
HERD 1
Across
Within
Across
HERD 3
Performance recording – BLUP
 ‘individual animal model’ used: for each animal its own
performance records are used as well those of its relatives
 data on all performance traits analysed simultaneously
taking into account correlations between traits and the
heritability of the traits
 Estimated Breeding Values (EBVs) produced for each animal
for each trait – these are the estimates of the genetic worth
of the animal
How do we assess performance?
Performance
records
BLUP
Pedigree
information
Trait Heritabilities
Trait Correlations
INDEXES
EBVs
Beef Performance Recording
Service Providers
 ‘Beefbreeder’ delivered by Signet
 ‘Breedplan’ delivered by Pedigree Cattle Services
Ltd
 Breeds use one service or the other
 Although the information provided by the two
systems may differ in some respects, the
approach and methods they use are similar.
Estimated Breeding Values (EBVs)
Terminal Sire
EBVs
Gestation Length (days)
Calving Ease Direct %
Easier calving
Birth Weight (kg)
200 Day Growth (kg)
400 Day Growth (kg)
(600 Day Growth (kg))
Efficient growth
(Carcase Weight (kg))
Muscle Score (points)
Muscle Depth (mm)
Fat Depth (mm)
(Eye Muscle Area (cm2))
(Rib Fat (mm))
(Intramuscular fat (%)
(Retail Beef Yield (%))
Saleable meat
Lean meat yield
Estimated Breeding Values (EBVs)
Maternal
EBVs
200 Day Milk (kg)
Longevity (years)
Udder Score (points)
Teat Score (points)
Age at First Calving (%)
Calving Interval (days)
Maternal Calving Ease
(Calving Ease (Daughters))
Cow Weight (kg)
Scrotal Circumference (cm)
Docility (t.b.a)
Signet (Beefbreeder) Index
Gestation Length (days)
Calving Ease Direct %
Birth Weight (kg)
200 Day Growth (kg)
400 Day Growth (kg)
(600 Day Growth (kg))
(Carcase Weight (kg))
Beef Value
Muscle Score (points)
Muscle Depth (mm)
Fat Depth (mm)
(Eye Muscle Area (cm2))
(Rib Fat (mm))
(Intramuscular fat (%)
(Retail Beef Yield (%))
Ranks animals on the
expected financial merit
of the offspring’s
carcases
ABRI (Breedplan) Index
Gestation Length (days)
Calving Ease Direct %
Birth Weight (kg)
200 Day Growth (kg)
400 Day Growth (kg)
(600 Day Growth (kg))
(Carcase Weight (kg))
Muscle Score (points)
Muscle Depth (mm)
Fat Depth (mm)
(Eye Muscle Area (cm2))
(Rib Fat (mm))
(Intramuscular fat (%)
(Retail Beef Yield (%))
Terminal Sire Index
The economic value of an
animal to produce prime
steers and heifers for beef
production.
Signet (Beefbreeder) Index
Gestation Length (days)
Calving Ease Direct %
Birth Weight (kg)
200 Day Growth (kg)
400 Day Growth (kg)
(600 Day Growth (kg))
(Carcase Weight (kg))
Muscle Score (points)
Muscle Depth (mm)
Fat Depth (mm)
(Eye Muscle Area (cm2))
(Rib Fat (mm))
(Intramuscular fat (%)
(Retail Beef Yield (%))
Calving Value
To improve financial
returns by reducing
costs associated with
extended gestation
lengths and difficult
calvings
EBLEX FRED
Born: 25/06/05
Sire
Dam
WINTERHILL BOB
BRADWELL LIZ
Analysis
Date:
Calving
Value
200 Day
Milk
(kg)
200 Day
Growth
(kg)
400 Day
Growth
(kg)
EBV
2C
+1
+ 20
+ 32 + 4.8 - 0.2
Accuracy
%
85
45
82
29/11/2006
85
Muscle
Depth
(mm)
78
Fat
Depth
(mm)
75
100 Day Wt.
200 Day Wt.
300 Day Wt.
400 Day Wt.
500 Day Wt.
Scanned
172
308
486
672
812
Yes
Beef Value
26
81
Accuracy Values
Accuracy…
 Indicates the amount of data used to calculate the EBV / Index
 Expressed as a %
 Influence by the following…
 Whether the animal has been measured for the trait
 Whether relatives have been measured for the trait
 How heritable the trait is (since all are different)
 The amount of information on correlated traits both from the
animal itself and its relatives
 The number of contemporaries recorded
 Is a measure of RISK
Accuracy Values
EBLEX FRED
And is a +ve or a
-veDam
EBV a good or a
bad thing?
BRADWELL
LIZ
Born: 25/06/05
So, how good Sire
is
32kg for
400 Day
WINTERHILL
BOB
Growth?
Analysis
Date:
Calving
Value
200 Day
Milk
(kg)
200 Day
Growth
(kg)
400 Day
Growth
(kg)
EBV
2C
+1
+ 20
+ 32 + 4.8 - 0.2
Accuracy
%
85
45
82
29/11/2006
85
Muscle
Depth
(mm)
78
Fat
Depth
(mm)
75
100 Day Wt.
200 Day Wt.
300 Day Wt.
400 Day Wt.
500 Day Wt.
Scanned
172
308
486
672
812
Yes
Beef Value
26
81
How to Use EBVs & Indexes
Trait
Calving Value
200 Day Milk (kgs)
200 Day Growth (kgs)
400 Day Growth (kgs)
Muscle Depth (mm)
Fat Depth (mm)
Beef Value
Bottom 10% Bottom 25% Breed Avg
-1C
-3
0
0
-0.1
0.1
6
0C
-2
5
10
0.5
0
11
1C
0
12
21
1.3
-0.1
16
Top 25% Top 10%
2C
1
18
31
2.1
-0.2
20
3C
3
24
41
3
-0.3
24
Why use EBVs?
 Real Farm Example:
– Marmaduke
– Neptune
Beef Value Top 10%
Beef Value Below Average
 Result:
– The Marmaduke advantage:
•
•
•
•
Bull calves 15kg heavier and finished 17 days earlier
Heifer calves 9kg heavier and finished 30 days earlier
Plus improved conformation in both cases
Worth on average extra £50/calf
Why use EBVs?
 Real Farm Example:
– Marmaduke
– Neptune
Calving Value Bottom 5%
Calving Value Top 10%
 Result:
– The Marmaduke disadvantage:
•
•
•
•
17% more difficult calvings
2.25% more caesareans
4% more calf deaths
Cost an extra £10/cow mated (on average)
Conclusions:
1). EBVs are a good predictor of performance
2). Remember to check all the traits when selecting a bull
Producers are using EBVs to select
stock bulls
Industry evidence – (Perth Sales February 08)
TOP 1% bulls on Beef Value
9 sold to average £8120
TOP 10% bulls on Beef Value
26 sold to average £4248
TOP 25% bulls on Beef Value
22 sold to average £3107
AVERAGE bulls Beef Value
14 sold to average £3000
New Breeding Technologies
 Selection conventionally based on effects of
genes rather than on genes themselves
 New molecular techniques allow genes and
‘markers’ to be identified on the chromosome
Useful for traits that…
 Have low heritability
 Are difficult / expensive to measure e.g. disease resistance
 Can not be measured until the next generation
 Are not routinely measured e.g. meat tenderness
 Are phenotypically but not genetically correlated with a trait
 you do not want to increase e.g. marbling and back fat
Breeding Summary
 Three main methods of genetic improvement of
beef cattle in UK
 Breed substitution
 Cross breeding (exploiting hybrid vigour)
 Within-breed selection (perf. recording)
 Performance cannot be judged by eye alone
 EBVs and Indexes are the best indicators of
breeding potential
 EBVs and Indexes are easy to use and their
commercial value is well proven
Further information
www.eblex.org.uk
Material produced for EBLEX Better Returns Programme
by Signet
© Signet 2009
For further information contact:
www.signetfbc.co.uk