genetic improvement of brahman in southern africa prof norman maiwashe (phd, pri sci nat)...
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Genetic improvement of Brahman in Southern Africa
Prof Norman Maiwashe (PhD, Pri Sci Nat)Agricultural Research Council, Private Bag X2, Irene 0062
University of the Free State, PO Box 339, Bloemfontein 9300
2014 Brahman World Congress, 8 April 2014, South Africa
Outline
1• Background
2• Brahman in SADC
3• Performance recording
4• Genetic evaluation and selection
5• Summary
Fundamentals of genetic improvement
• Genetic improvement refers to beneficial genetic change
Superiority of selected animals
Genetic Change = Accuracy of selection criterion
per year Genetic variation
/ Generation Interval
EBV is the most accurate selection criterion
You need performance to get EBV
Qualities of Brahman cattle
Hardiness AdaptabilityGood mothering abilityHeat tolerance Disease resistance Parasite resistance
First importation of Brahman to SADC – 1950s
A lot happened since the first importation of Brahman
• Some interesting statistics on Brahmans in the SADC
Brahman is one of the most popular breeds in SADC
South African figures
Number of animals recorded annually in major SA breeds
Brahman in SADC
Few countries in SADC have formal Brahman Breeders Societies
Genetic Improvement
• Breeding Goal
• Selection Criteria
• Genetic Evaluation
• Selection and breeding
Breeding Goal of the Brahman
• Breeding of animals that:– are adapted, – have desired conformation, – highly fertile (both bulls and cows), – achieves acceptable growth rates and – would be preferred by commercial producers
• Are all Brahman breeders selecting towards this Goal?
Performance Recording
NAM RSA
0
20
40
60
80
100
Recording Not-recording
% F
arm
ers
• Levels of performance recording differs among the SADC countries
Acc
urac
y of
se
lect
ion
Brahman breeders are taking performance recording seriously!
• Implementation of a Completeness of Performance Herd Rating System
• It summarizes the quantity of pedigree and performance data
Collaboration between ARC and SA Brahman
1. Collection of feed intake data through central test centers
2. Ultrasound scanning of animals
Non-exhaustive list of traits measured
• Birth weight • 200-, 400- and 600-day weight • Mature weight
• Days to calving• Gestation length• Scrotal size • Docility
• Structural / conformation, • Behavioral traits
• Ultrasound measures:– Rump and rib fat thickness– Eye-muscle area and– Intramuscular fat
percentage
Regional Genetic Evaluation conducted by BreedPlan
Genetic trends for growth traits
± 10kg
± 6 kg
± 8 kg
±0.5 day
±0.5 day
±0.2 cm
What to make of the genetic trends?
• Selection using many breeding values could result in undesirable response in other economically important traits– Traits are genetically correlated
It can get worse …1. Birth direct2. Birth maternal3. Weaning direct4. Weaning maternal5. Total maternal6. Yearling direct7. 600 d direct8. Calving direct9. Calving maternal10. Carcass weight11. Rib fat12. Rump fat13. LMA14. Marbling score15. Quality grade16. % Retail yield17. Pounds (kg) retail yield18. Yield grade19. US LMA20. US rib fat21. US % IMF22. Fat percentage23. Condition score
24. Gestation length25. Days to calving26. Calving interval27. Stayability28. Heifer pregnancy rate29. Rebreeding rate30. Calf weaned/cow exposed31. Scrotal circumference32. Pelvic area33. Frame score34. Muscle score35. Udder score36. Docility37. Tick score38. Parasite egg count39. Mature weight40. Maintenance energy41. Feed efficiency42. Drop weight43. Type score44. Uterine score45. Tooth score46. Precocity score
47. Feedlot feed consumption48. Feedlot survival49. Pre-wean survival50. Serving capacity51. Serving proportion52. Semen volume53. Hip height54. Leg score55. Length productive life56. Doing ability57. Grand-maternal weaning58. Twinning rate59. Days to 11mm BF60. Days to 75% Choice61. Days to carcass weight62. Hair whorl score63. Average daily gain64. Weight /day of age65. Liver weight66. Resting heart rate67. Pulmonary arteriole pressure68. Brisket disease rate69. Bravery70. Aggression
Prof Bruce Golden, USA
Mission impossible
Breeding objectives – Rand/Dollar Value
• There is a need for unified or optimal selection tool– That takes antagonisms amongst traits into account
• Selection Index (Rand-Values) provides such a tool
Rand-Value Index = Breeding Values * Economic Values
Recent development on Rand-Values
• Namibia has led the way• South Africa has recently implemented a Rand-Value
Index• The Rand-values represent different production-
marketing systems
1. Brahman Rangeland Grazing Index
2. Brahman Wean Index
3. Brahman Feedlot Index
Summary
1. Good progress in the Brahman is partially attributable to a good pace of adoption of science and technology amongst breeders
2. Regional integration in design and implementation of genetic improvement in the breed should be encouraged
3. Investment in research and development is essential to ensure that the breed remain competitive
Summary
4.Opportunity for the breed– Increase in the demand for animal protein– Communal and emerging farming community – Climate change
5. Threat to breed improvement– Inconsistent breeding goal
Beautiful Animals Productive Animals
Thanks for Your Attention
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