The Game Breeding Game: What are the rules of the game?

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Charleen York
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SA Stud Book Elite Breeding Symposium 30 April 2014 Bloemfontein Jacques van

1 The Game Breeding Game: What are the rules of the game? The Game Breeding Game: Where are we heading? SA Stud Book Elite Breeding Symposium 30 April 2014 Bloemfontein Jacques van Rooyen Pri.Sci.Nat Faculty of Veterinary Science, University of Pretoria & Boscia Wildlife Solutions Jacques van Rooyen & Helena Theron

2 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

3 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: mil animals Economic significance 5 th largest agric 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

4 The Basic Principle of gene expression (P)henotype = (G)enotype + (E)nvironment = + 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

5 The shift in focus (P)henotype = (G)enotype + (E)nvironment = + Game Ranger to Game Rancher

6 Ranger vs. Rancher Game Ranger: Priorities: Conservation of species I.e. preserving and managing the environment in which a population of a species could naturally survive Managing any threat to the Buffalo survival of the population Roan Thus: optimizing for survival Sable 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 Do we fully understand what we do?

7 Horn Length WHAT IS THE GAME INDUSTRY MAINLY LOOKING AT?

8 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

10 HORN LENGHT DOES PAY!! BUT SHOULD WE ONLY SELECT FOR HORN LENGTH??

11 The Soay Sheep example Nature - Johnston et al 2013

12 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 Ho P small horns = increased survival Heterozygote advantage in Ho + Ho P

13 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!

14 The case of the Texas Longhorn... Hillis, D.M. (2005)

6) Disposition (0.4) and the low and even neg. corr.

15 The Texas Longhorn Example Texas Longhorn: 40 years of selecting for Horn Length = Benchmark from 40 to 80 (Hillis 2005) BUT!! Given the heritability of many other NB traits such as: Milk production (0.35) Scrotal circumference (0.48) Disease resistance ( ) 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) 40 Years Limb, Don. (2005) Hillis, D.M. (2005)

16 Horn growth and reproduction: Sable & Roan antelope

17 Pearson s square Correlations between body measurements of 49 sable antelope bulls Horn Length Horn Base Horn Rings Tip Tip Ear Length Body Weight Testis circumfr. Age Horn Length < Horn Base Horn Rings < Tip Tip Ear Length Body Weight < Testis circumfr < Age

18 Correlation of serum testosterone with body measurements in roan & sable bulls Roan antelope (n=5) Sable antelope (n=10) Measurement ū SD Coeff. / P-value ū SD Coeff. / P-value Testosterone Horn Length Horn Base Horn Rings ** Testis circumference Age Weight **

19 Horn growth and reproduction: Sable antelope Horn Length and NB reproduction traits are not necessarily linked What should we select for..?

20 mm 200 Sable Horn Length Matetse Bulls Matetse Cows Malawi Cows Malawi Bulls Zambian Bulls Zambian Cows Age (years)

21 300 Horn Base Circumference Age (Years)

22 300 Sable body weight Male female

23 350 Testes Circumference of Sable bulls Age (years)

24 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 Hillis, D.M. (2005) ARE THESE PROCESSES IN PLACE IN GAME BREEDING?

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.

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.

25 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 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!!

RED T12 Record keeping systems in game Bona Banzi Exclusive Game Movement / Capture Entry Sheet 2014/04/22 Date of Capture 2013/10/11

(mm/day) 0.99 Horn Measurements Left Right Length 10 10 Rings 0 0 Tips 10 10 Spread Base Circumference 5.75 5.

Left Right ID Parental Information Length Red T12 Vaar Mother Rings Name Red T12 Trust Red 902 Tips M/Chip No 945000001116696

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

26 RED T12 Record keeping systems in game Bona Banzi Exclusive Game Movement / Capture Entry Sheet 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 Rings 0 0 Tips Spread Base Circumference Date of Capture Attending Vet Place of Capture Age at capture (month) Reason for Capture Avg Growth (mm/day) Horn Measurements Left Right ID Parental Information Length Red T12 Vaar Mother Rings Name Red T12 Trust Red 902 Tips M/Chip No C3E 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

27 Record keeping systems in game AnimalID AnimalCategoryID Species MicrochipNumber MicrochipSite TagOrNotcDNASpeciStudCertificGender DateofBirth DateofPurchasAmountPa FatherID MotherID Terminatio C Left neck y /05/ Auctioned E Left neck Y /03/ Sold C6C02 Left neck Y /03/ Auctioned E5C49 Left neck B /05/ Sold F Left neck B /03/ Auctioned F7D7A5010 Left tail base Y /06/ sold C21 Right neck G /05/ Auctioned Right neck G /07/ Auctioned F6B7C Right neck G /04/ Auctioned C6B71 Right neck O /02/ Sold A0556 Left neck B /08/ Sold A76 Right neck G /02/ Auctioned Right neck G /02/ Auctioned B5E6800 Right neck R /02/ Sold A Unknown R /01/ Auctioned B0A Unknown R /01/ Auctioned Left neck Y /08/ Sold A29 Left neck Y /08/ Sold E055B Right neck Y /08/ Sold E1E Right neck B /02/ Sold E3E5163 Left neck Y /02/ Sold Left tail base Y /02/ Sold E Right neck Y /08/ Sold

28 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

29 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

30 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

31 Thank You!!

Estimating breeding value

Estimating breeding value Key terms Estimated breeding value (EBV) Heritability Contemporary groups Using information from relatives Accuracy Which animal to select? Animal P1 P2 EBV sire's perform. Index