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Improving Animals Each Generation by Selecting from the Best Gene Sources. The Next Generation. 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
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Improving Animals Each Generation by Selecting from the Best Gene Sources
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 ~$30 million to date • 12,670 daughters already milking • 10,401 in United States • 590 in France, 570 in Italy, 400 in Denmark, 262 in the Netherlands, etc.
Computer Mating Programs • For 5 million dairy cows, mate is selected by computer programs • Inbreeding avoided using pedigrees • Carriers of same defect not mated • Weak traits of cow matched to strong traits of bull • Sires with easy birth chosen for first calf
Single Genes • Some breeds horned (TX longhorn) • Other breeds 100% polled (Angus) • Wild bulls/cows needed horns • Genetic dehorning is easy • Polled (no horn) gene is dominant • Other genes are more valuable
Specialized Animals • Cattle • Dairy, not selected for meat quality • Beef, not selected for milk quality • Chickens • Layers, not selected for meat yield • Broilers, not selected for egg yield • Global use of improved varieties
Breeding Companies • Poultry, swine • Closed, private breeding populations • Central control and vertical integration • Dairy, beef cattle • Open exchange of breeding stock • Producers choose using genetic rankings • Almost no patents or intellectual property
Animal vs. Vegetable Food Costs$ / 50 g protein needed daily
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