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Practical Bull Selection for YOUR Situation. Jared E. Decker DeckerJE@missouri.edu http:// steakgenomics.blogspot.com. Decisions. Practice what you preach…. Overview. Have a Plan Use economic selection indexes Use genomic-enhanced EPDs. What would you do….
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Practical Bull Selection for YOUR Situation Jared E. Decker DeckerJE@missouri.edu http://steakgenomics.blogspot.com
Overview • Have a Plan • Use economic selection indexes • Use genomic-enhanced EPDs
What would you do… If you were driving from Brooksville, Florida to Miles City, Montana?
Have a Plan • Identify the marketing endpoint for your operation • Do you sell cattle at weaning? • Do you retain ownership through the feedlot? • Do you sell to a specialty market?
Have a Plan • Are you going to crossbreed or straightbreed? • If you crossbreed, which breeds will you use? • Must have a plan!
Have a Plan • What economically relevant traits influence your bottom line? • Take an inventory of your herd • Which traits need improvement?
Have a Plan • Why would I want to develop a plan (a.k.a. breeding objective)? • Focus selection decisions on our economic well being • Make selection decisions more accurately and consistently • Simplifies evaluation of candidates for selection Courtesy of Michael MacNeil
Factors to consider in Selection Decisions Number of calves Weight of calves Body composition Product quality Number of cull cows Weight of cull cows Expense Nutrients required Number of replacements Interventions Medical care Genetic load Income Courtesy of Michael MacNeil
Economically relevant traits Number of calves Weight of calves Body composition Product quality Number of cull cows Weight of cull cows Nutrients required Number of replacements Interventions Medical care Genetic load Income Expense Courtesy of Michael MacNeil
EPDs Inform selection decisions for Income • Number of calves • Heifer pregnancy, sustained reproductive success, stayability, calving ease • Weight of calves • Weaning weight, yearling weight, carcass weight • Body composition • Yield grade (carcass weight, fat depth, ribeye area) • Product quality • Marbling score • Tenderness • Number of cull cows • Heifer pregnancy, sustained reproductive success, stayability, calving ease • Weight of cull cows • Mature weight Courtesy of Michael MacNeil
EPDs inform selection decisions for Expenses • Nutrients required • Mature weight, weaning weight maternal (milk), feed intake • Number of replacements • Heifer pregnancy, sustained reproductive success, stayability, calving ease • Interventions • Calving ease, docility, udder quality, ? • Medical care • No EPDs currently available, under development • Genetic Load Courtesy of Michael MacNeil
Questions • That is a lot of EPD to consider at one time – genetic improvement would be faster if I considered few traits, right? • That depends on how you define “genetic improvement”: the individual traits would change more quickly by considering fewer of them, but the increase in genetic potential for profit would be slower. Courtesy of Michael MacNeil
To index… or not to index? How do I keep all the economically relevant traits in balance and moving in the right direction? Courtesy of Michael MacNeil
To index… or not to index? USE INDEXES!!! Courtesy of Michael MacNeil
What is an economic index? • Combination of EPDs weighted according to their economic importance • Expressed as a dollar value • Breeds have different indexes • Different indexes for different marketing endpoints
Economic Index Example • Can sort by any of the $Indexes • When would we want to use $Beef index? • Can put restrictions on other traits as well
Economic index selection • Humans have certain advantages • Computers have other advantages • Computers are really good at analyzing large amounts of data! • Use them!
Quiz Time: Which Bull? Bull A: Bull B:
Quiz Time: Which Bull? Bull A: BMI$: Baldy Maternal Index CEZ$: Calving Easy Index BII$: Brahman Influence Index CHB$: Certified Hereford Beef Index Bull B:
Quiz Time: Which Bull? Keeping replacement females Bull A: BMI$: Baldy Maternal Index CEZ$: Calving Easy Index BII$: Brahman Influence Index CHB$: Certified Hereford Beef Index Bull B:
Quiz Time: Which Bull? Retaining ownership in feedlot Bull A: BMI$: Baldy Maternal Index CEZ$: Calving Easy Index BII$: Brahman Influence Index CHB$: Certified Hereford Beef Index Bull B:
Quiz Time: Which Bull? Answer: They are the same bull! Bull A: BMI$: Baldy Maternal Index CEZ$: Calving Easy Index BII$: Brahman Influence Index CHB$: Certified Hereford Beef Index Bull B:
Genomic-enhanced EPDs • Provide more accurate estimates for young animals • Reduce risk • Help manage inventory and make selection decisions • Identify differences between full siblings
Take Home • Economic indexes simplify and improve selection decisions • Genomic-enhanced EPDs work and provide more information for young animals
Thank You! Questions? http://steakgenomics.blogspot.com