2026 FULL SOLUTION
◉ a selection index allows you to look at one or more traits and
derive a comprehensive ___ for an animal Answer: BV
◉ Because a litter is raised by one dam, often the performance of
littermates will be more alike than you would expect given the
proportion of genes they have in common. This effect, denoted as
(c^2), is known as ___ Answer: common environmental effect
◉ the average performance of many progeny is a good indication of
an individuals _____ Answer: BV
◉ an EPD based on an animals own data is _______more accurate than
one based on a number of his progeny Answer: not always
◉ T/F: the baseline used to compare birthweight EPDs is a standard
reference number used by all beef cattle breed associations Answer:
false
◉ heritability for a litter size is 0.4. When computing the accuracy of
an EPD for litter size, h^2 = ? Answer: 0.4
,◉ T/F: threshold traits are better selected for directly rather than by
a correlated trait Answer: false
◉ bill uses a selection index based on 3 traits. Ted uses an index
based on 6 traits. Whose index provides the greatest overall
selection intensity? Answer: Bill
◉ What are the 2 possible causes for the phenomenon of correlated
traits? Answer: pleiotropy and linkage (ex. lack of recombination)
◉ For birthweight:
Bull A: Angus EPD = +2 ACC = 0.99
Bull B: Charolais EPD = -2.5 ACC = 0.8
which is better? Answer: cannot choose with the info given
(different breeds so you can't compare them)
◉ when heritability is ____, a sires own performance data is valuable
when estimating his EPD for that trait Answer: high
◉ given the following equation, one would assume...
(delta BV y given x)/t = (r bvx, bvy) (acc of x)(i)(sigma bv y) / L
Answer: direct selection for trait x may influence the BV for trait y
, ◉ "paternal half sibs" refer to: Answer: half sibs of the sire
◉ what does r BVx, BV (hat)x represent? Answer: accuracy
◉ if CR is high, accuracy is ___ Answer: low
◉ if CR is high, PC is ____ Answer: high
◉ CR and PC are ____ related Answer: positively
◉ CR and PC are ___ related to accuracy Answer: negatively
◉ c Answer: c
◉ Bonus: where was kojima the morning of April 8 Answer: award
ceremony for her children
◉ i/t = rate of ___ change over ___ Answer: BV, time
◉ Accuracy of selection: the accuracy of predicting ____ Answer: BV