5) A swine breeder is selecting for increased number of pigs weaned (NW) and reduced backfat (BF) in her pigs. She plans to choose three out of the following eight boars based on EBVs for these traits. Boar | EBV for Number of Pigs Weaned | EBV for Backfat (inches) 1 | +1.1 | -0.11 2 | +0.8 | -0.25 3 | +2.4 | -0.05 4 | +0.3 | -0.36 5 | -0.5 | -0.10 6 | +3.0 | +0.20 7 | +1.0 | +0.05 8 | -0.6 | -0.40 a) Which boars would she initially select using tandem selection when NW is the first trait under selection? b) Which boars would she initially select using tandem selection when BF is the first trait under selection? c) Which boars would she select using independent culling levels if the levels were set at 0 pigs for NW and -0.10 inch for BF? d) Which boars would she select using an economic selection index if an independent one-pig increase is NW is worth $100.00 and an independent 1-inch difference decrease in BF is worth $1,000.00? e) Why would boar 8 be selected with the index (d) but not with independent culling levels (c)?
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Tandem selection involves selecting for one trait at a time. Independent culling levels involve setting minimum acceptable levels for each trait and culling any animals that do not meet these levels for every trait. Economic selection index combines the economic Show moreā¦
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