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The Game Breeding Game: Where are we
heading?
Jacques van Rooyen
& Helena Theron
The Game Breeding Game: What are the rules of the game?
SA Stud Book Elite Breeding Symposium30 April 2014
Bloemfontein
Jacques van Rooyen Pri.Sci.NatFaculty of Veterinary Science, University of
Pretoria
&
Boscia Wildlife Solutions
Contents
1. The game industry: overview and trends
2. Principles of breeding and selection
3. Shift from Ranger to Rancher
4. Game Breeding- What we know & don’t know:
1. Soay sheep
2. Texas longhorn cattle
3. Sable and Roan antelope
5. Record keeping and selection in game
6. The future: genetic management and selection
Game Industry: Why is it important?
Number of game farms: 2,280 (1980) to ±10,000 today
Surface area: 20,5 mil ha (24% of SA rangelands)
Number of game: Vary: 2.5 – 18.6 mil animals
Economic significance 5th largest agric sector @ R10bil GDP
Plains Game Recent reduction in sale intensity (saturation..?) (Brandon Leer)
High value species/varieties Significant price growth over 10 years... For how long? Competition in animal
performance will increase.
Future: increased competition = increased importance of sound breeding practises –MEASURING AND RECORDING WILL PAY
What to measure and what to record???
Du Toit et al 2013, ABSA,
WRSA 2013, LBW etc
(P)henotype =
= +
+(G)enotype (E)nvironment
The Basic Principle of gene expression
The animal and its performance is a product of the interaction between its genetic potential
and the ability of the environment to express its genetic potential.
Variance between animals will be because of differences in either their genetic composition
or environment or both
(P)henotype =
= +
+(G)enotype (E)nvironment
The shift in focus…
Game Ranger to Game Rancher
Ranger vs. Rancher
Game Ranger:
Priorities:
Conservation of species
I.e. preserving and managing the environmentin which a population of a species could naturally survive
Managing any threat to the survival of the population
Thus: optimizing for survival
Allow natural selection and the survival of the fittest…
Game Rancher:
Priorities:
Financial gain
I.e. Optimizing both the environment and the genetic composition of a population to optimize animal performance for higher profits
Management & Selection objectives
Animal improvement
Thus: optimizing for performance & profit
Breeder select animals based on selection objectives & criteria
Buffalo
Roan
Sable
Do we fully understand what we do?
Horn Length
WHAT IS THE GAME INDUSTRY MAINLY LOOKING AT?
The current trend: breeding &
valuation of genetic potential...
Single trait selection: Emphasis on horn length (coat colour/combination)
as only trait of economic importance
Selection mainly for horn length
Value of animal: Value of animal based on measured horn length =
subjectively because not necessarily linked to true genetic potential/merit where environmental influence has been accounted for
Value of animal often strongly associated with value of sire or dam
HORN LENGHT
DOES PAY!!
BUT SHOULD WE
ONLY SELECT FOR
HORN LENGTH??
The Soay Sheep example
Nature - Johnston et al 2013
The Soay Sheep example
Significant variation in horn length of rams
One gene: Relaxin-like receptor 2 (RXFP2) Genetic & phenotypic data of 1,750 over 21 years
Two alleles: Ho+ - large horns = high
reproductive success
HoP – small horns = increased survival
Heterozygote advantage in Ho+HoP
The Soay Sheep example
• Mechanism for RXFP2 influence on survival and reproductive success is
unknown....
• Might be due to energy expenditure in three phenotypes, especially
during rut
•NB!! Substantial genetic and phenotypic data!
The case of the Texas Longhorn... Hillis, D.M. (2005)
The Texas Longhorn Example
Texas Longhorn: 40 years of selecting for Horn Length = Benchmark ↑ from 40” to 80” (Hillis2005)
BUT!!
“Given the ↑ heritability of many other NB traits such as: Milk production (0.35)
Scrotal circumference (0.48)
Disease resistance (0.4 – 0.6)
Disposition (0.4)
and the low and even neg. corr. between HL and some other desirable traits , a program that selects only for HL will most certain suffer in overall quality in the long term” (Hillis, 2005)
AND
For NB Traits, most progeny of exceptional parents will not be exceptional… (Hillis 2005)
Limb, Don. (2005)
Hillis, D.M. (2005)
40 Years
Horn growth and reproduction:
Sable & Roan antelope
Horn Length Horn Base Horn Rings Tip – Tip Ear Length Body WeightTestis
circumfr.Age
Horn Length 1.0000.200
0.167
0.706
<.0001
-0.066
0.654
0.115
0.430
0.203
0.161
0.175
0.230
0.309
0.031
Horn Base0.200
0.1671.000
0.032
0.825
-0.004
0.980
0.018
0.903
0.108
0.460
0.190
0.192
0.112
0.446
Horn Rings0.706
.<.0001
0.032
0.8251.000
0.018
0.901
0.116
0.427
0.161
0.270
0.113
0.441
0.458
0.000
Tip – Tip-0.066
0.654
-0.004
0.980
0.018
0.9011.000
0.039
0.790
0.350
0.014
0.134
0.359
-0.160
0.271
Ear Length0.115
0.430
0.018
0.903
0.116
0.427
0.039
0.7901.000
0.318
0.026
0.246
0.088
-0.047
0.748
Body Weight0.203
0.161
0.108
0.460
0.161
0.270
0.350
0.014
0.317
0.0261.000
0.577
<.0001
-0.204
0.159
Testis
circumfr.
0.175
0.230
0.190
0.192
0.113
0.441
0.134
0.360
0.250
0.088
0.577
<.00011.000
-0.003
0.986
Age0.309
0.031
0.112
0.446
0.458
0.000
-0.160
0.271
-0.047
0.748
-0.204
0.159
-0.003
0.9861.000
Pearson’s square Correlations between body measurements
of 49 sable antelope bulls
Correlation of serum testosterone with body
measurements in roan & sable bulls
Measurement
Roan antelope (n=5) Sable antelope (n=10)
ū SD
Coeff. /
ū SD
Coeff. /
P-valueP-value
Testosterone 3.144 2.536 - 5.183 4.335 -
Horn Length 484.8 80.369
0
883.2 7.909
-0.116
1 0.751
Horn Base 227.2 13.461
0.461
255.2 7.33
0.231
0.434 0.521
Horn Rings 14.100** 3.943
0.975
27.85 2.625
0.262
0.005 0.464
Testis
circumference 162.2 10.849
-0.1
221.000 14.974
0.742
0.873 0.014
Age 3.2 0.447
0.707
4.25 0.791
0.384
0.182 0.273
Weight 205.000** 16
0.9
208.8 18.79
0.261
0.037 0.466
Horn growth and reproduction: Sable antelope
Horn Length and NB
reproduction traits are
not necessarily linked
What should
we select for..?
0
200
400
600
800
1000
1200
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
mm
Age (years)
Sable Horn Length
Matetse Bulls
Matetse Cows
Malawi Cows
Malawi Bulls
Zambian Bulls
Zambian Cows
0
50
100
150
200
250
300
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Age (Years)
Horn Base Circumference
0
50
100
150
200
250
300
0 365 7301095146018252190255529203285365040154380474551105475
Sable body weight
Male
female
0
50
100
150
200
250
300
350
0 2 4 6 8 10 12
Age (years)
Testes Circumference of Sable bulls
Animal Selection Principles
Most Economic NB traits are:
quantitative (additive)
Influenced by many genes
Continuous variation
Large environmental influence
Breeding value determined
statistically, based on individual, pedigree
& progeny performance
IMPLICATIONS:
1. Selection objectives
2. Setting of norms/standards/criteria
3. Record keeping (Measure)
1. Identification & parenting
2. Basis for comparison
3. Degree of variation
4. Heritability / Breeding values
ARE THESE PROCESSES IN PLACE IN
GAME BREEDING?
Hillis, D.M. (2005)
Criteria and records: Breeding Bull
Breeding bulls has the biggest genetic
impact on a herd over time.
Important Traits to Record & Select for :
1. Body Conformation:
1. Highly heritable
2. Functional efficiency (body weight, legs, male
characteristics etc.
2. Pedigree & Progeny:
1. What do you pay for…? Breeding value?
2. Performance of offspring
3. Best: Good parents and all the other criteria
3. Horn Growth:
1. Economic very NB Trait
2. Heritability vs Nutrition (Environment) 1. Highly heritable in Bighorn Sheep (0.69) (Coltman et al.
’03
2. Contemporary groups & indexes.
4. Reproductive ability:
1. Fitness, sperm count, libido etc.
5. Health & Disease Resistance:
1. Natural selection kept them healthy – keep it
that way!!
2014/04/22
Date of Capture 2013/10/11 Attending Vet Bossie
ID Red T12 Place of Capture Bona Banzi Age at capture (month) 8
Reason for Capture Move to Buisfontein Avg Growth (mm/day) 0.99
Horn Measurements Left Right
Length 10 10
Rings 0 0
Tips 10 10
Spread
Base Circumference 5.75 5.75
Date of Capture Attending Vet
Place of Capture Age at capture (month)
Reason for Capture Avg Growth (mm/day)
Horn Measurements Left Right
ID Length
Red T12 Vaar Mother Rings
Name Red T12 Trust Red 902 Tips
M/Chip No 945000001116696 4C3E333905 Spread
Tag No Red T12 Red G30 Red 902 Base Circumference
Old Tag No N/A N/A N/A
Age (months) 15 6 years 64 Date of Capture Attending Vet
Date of Birth 2013/01/27 Feb-06 Jan-09 Place of Capture Age at capture (month)
Sex Male Male Female Reason for Capture Avg Growth (mm/day)
Species Sable Sable Sable Horn Measurements Left Right
Subspecies X Zambian X Length
Rings
Calf Intervals Date Calf Name Sex Tips
Spread
Base Circumference
Bona Banzi Exclusive Game Movement / Capture Entry SheetR
ED
T1
2
3
Parental Information
Record keeping systems in game
Record keeping systems in game
AnimalID AnimalCategoryID Species MicrochipNumber MicrochipSite TagOrNotchNumberDNASpeciesClassificationStudCertificationNumberGender DateofBirth DateofPurchaseAmountPaidFatherID MotherID Termination
37 1 3 470C330024 Left neck y64 2 2 2002/05/16 0.00 0 Auctioned
38 1 3 423431326E Left neck Y35 1 2002/03/16 0.00 0 0 Sold
40 1 3 44455C6C02 Left neck Y36 1 2002/03/16 0.00 0 0 Auctioned
41 1 1 44256E5C49 Left neck B37 1 2002/05/16 0.00 0 0 Sold
42 1 3 442567433F Left neck B38 1 2002/03/15 0.00 0 0 Auctioned
43 1 3 7F7D7A5010 Left tail base Y39 1 1999/06/20 0.00 0 0 sold
44 1 1 4426692C21 Right neck G36 1 2002/05/07 0.00 0 0 Auctioned
45 1 1 4427116603 Right neck G37 1 2002/07/07 0.00 0 0 Auctioned
46 1 1 44455F6B7C Right neck G38 1 2002/04/07 0.00 0 0 Auctioned
47 1 1 44442C6B71 Right neck O1 1 2002/02/07 0.00 0 0 Sold
48 1 1 44255A0556 Left neck B1 2 1999/08/11 0.00 0 0 Sold
49 1 1 4422362A76 Right neck G39 1 2002/02/11 0.00 0 Auctioned
50 1 1 4426705810 Right neck G40 1 2002/02/11 0.00 0 0 Auctioned
51 2 8 423B5E6800 Right neck R4 1 2000/02/11 0.00 0 0 Sold
52 1 2 442250647A Unknown R39 1 2002/01/11 0.00 0 0 Auctioned
53 1 2 4441121B0A Unknown R40 1 2002/01/11 0.00 0 0 Auctioned
54 2 8 4425705748 Left neck Y1 1 1998/08/21 0.00 0 0 Sold
55 2 8 4422486A29 Left neck Y41 1 1999/08/21 0.00 0 0 Sold
56 2 8 43154E055B Right neck Y11 1 1999/08/21 0.00 0 0 Sold
57 2 8 4315595E1E Right neck B4 1 1999/02/21 0.00 0 0 Sold
58 2 8 430E3E5163 Left neck Y42 1 1999/02/21 0.00 0 0 Sold
59 2 8 2046347274 Left tail base Y7 1 2000/02/21 0.00 0 0 Sold
60 2 8 431043190E Right neck Y16 1 1999/08/21 0.00 0 0 Sold
Record keeping systems in game
• All info of the animal is easily available at one glance
• Extra info available by clicking on the tabs
• Easy to record management as well as genetic info
• Easy to record as much or as little as you want to!
Conclusions:
Can’t just select for Horn Length
Need for a unified, balanced
breeding/selection criteria for each
species / objective
Record keeping in order to track changes
in all important traits in each species
Many research needs to take the industry
forward
Game breeders have a great responsibility
to the future viability of a specific
species/breed
Topics for discussion
Skills in the industry: What is required of a game
farm manager in future?
Size of our data basis Do we have large enough
data sets to move to more advanced tools for genetic selection?
BLUP, Genomics...
Is required record keeping feasible in game? Parentage
Performance data
What research is required? Trait heritability
Gene interaction
Thank You!!