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Goals of Animal Breeders • Provide the world’s food needs • Adapt animals to do new, more profitable jobs • Actual work (guide dog, draft horse) • Entertainment or companionship • Pharmaceutical production • Use modern selection tools
Natural Selection Tools • Mother nature uses these tools: • Starve, thirst, or freeze to death • Injury, infection, or disease • Eaten by predators • Males battle each other for mates • Harmful mutations abort or kill young • Mother nature obeys the law of the jungle
Artificial Selection Tools • Animal breeders use these tools: • Specialization of breeds and lines • Fence or barn or house • Import/export of genetic material • Artificial insemination, progeny test • Embryo transfer • Marker assisted selection • Animal breeders obey economic laws
Potential Future Tools • X, Y sorted semen (already in use) • Embryo splitting (some use) • Adult cloning • Transgenics • Genomic selection (main focus of research)
Family Size • Progeny test • Obtain 100 daughters of each bull • Measure important traits • Select the best bulls for further use • Descendants of 1 bull (Elevation) • 80,000 daughters • 2.3 million granddaughters • 6.5 million great-granddaughters
Data Analysis • National genetic rankings (dairy) • 200 million monthly records of milk yield and other traits • 30 million×30 million relationship matrix among cows and bulls • International genetic rankings • 27 countries on 5 continents • Combined ranking done in Sweden
Best BullO-Bee Manfred Justice • Semen sales 198,000 units/year • Semen price $40/unit • Income ~$30 million to date • 12,670 daughters already milking • 10,401 in United States • 590 in France, 570 in Italy, 400 in Denmark, 262 in the Netherlands, etc.
Computer Mating Programs • For 5 million dairy cows, mate is selected by computer programs • Inbreeding avoided using pedigrees • Carriers of same defect not mated • Weak traits of cow matched to strong traits of bull • Sires with easy birth chosen for first calf
Single Genes • Some breeds horned (TX longhorn) • Other breeds 100% polled (Angus) • Wild bulls/cows needed horns • Genetic dehorning is easy • Polled (no horn) gene is dominant • Other genes are more valuable
Specialized Animals • Cattle • Dairy, not selected for meat quality • Beef, not selected for milk quality • Chickens • Layers, not selected for meat yield • Broilers, not selected for egg yield • Global use of improved varieties
Breeding Companies • Poultry, swine • Closed, private breeding populations • Central control and vertical integration • Dairy, beef cattle • Open exchange of breeding stock • Producers choose using genetic rankings • Almost no patents or intellectual property
Conclusions • People improve the genetic merit of their animals each generation • Selection tools make fast progress • Improving animal production • Improving animal health • Animal protein is very affordable • North America has few citizens
Acknowledgments • Mel Tooker, Suzanne Hubbard, and Mark McGuire suggested several improvements