3. Importance of bull decisions
• A bull in natural service
normally sires 20 to 40
calves each year.
• Herd improvement, for
the most part, comes from
the sires chosen to
produce each calf crop.
• Ask yourself: What do I
want the bull to do other
than breed the cows?
4. What first?
• Analyze the market –
Determine what type of
animal is profitable to
produce. What do you
want the animal to do
other than breed cows?
• Decide what genetics are
needed to improve your
cow herd.
5. Bull selection criteria
• Physical evaluation – is the animal structurally
sound? In healthy condition? Show signs of
potential problems?
• Records – is there performance information
associated with the bull? What can you expect from
future progeny?
• Strategy – does the animal meet your specific herd
needs and goals?
6. Structural soundness
• Starts from the ground up
• Bull needs to be sound to
avoid injury and last
many years
• Structure is heritable –
offspring will have similar
traits
7. Structural soundness
• Scrotal size affects:
– The serving capacity of
the bull and hence the
number of times the cow
is served.
– The number of normal
sperm in each
service, which depends
on the size and condition
of the bull's testicles.
8. Phenotype + genotype
Understanding basic structure and physical
attributes are important, but studying
genetic and performance data is becoming
increasingly important in the beef industry.
9. Analyzing genetics
• Types of traits
– simply inherited:
differences among
animals are due to one
or two genes (i.e. hide
color).
– performance traits:
differences are due to a
number of genes (i.e.
birth weight, marbling).
11. Using technology
• Expected Progeny Differences (EPDs)
– Derived from performance records, pedigree
information and, where available, genomic data.
– 18 available EPDs available for sire selection tools.
12. Expected Progeny Difference
• An EPD is the expected difference in future
progeny performance of one individual compared
to another.
• Used to compare all cattle within a breed.
• EPD does not equal actual performance.
• Considering EPDs can help you make the best
possible bull decisions for your operation.
13. Example: Birth Weight
BW EPD
Bull A
-1.0
Bull B
4.0
• On average, Bull A’s calves are expected to weigh 5
pounds less than Bull B’s.
14. Example: Weaning Weight
•
Assumptions
– 67 Commercial Cows & 2
Herd Bulls
– 90% Calf Crop average (per
cow exposed)
– Sell all calves at weaning
– Feeder Calf Prices @
$1.40/pound
– Use Bulls for 5 years
– Bull 1 has weaning weight
EPD of +40 lb
– Bull 2 has weaning weight
EPD of +20 lb
Bull 1
Bull 2
16. 30 calves at 550#
30 calves at 570#
Bull 2
Bull 1
5 years
$1.40/lb
$115,500
$119,700
$4,200.00
Projected Gross
Value Difference
17. Before buying a bull
•
•
•
•
Think about specific herd needs
Study performance data and EPDs
Examine physical correctness
Be confident in the genetics you’re
purchasing
21. Crossbreeding
• Why crossbreed?
– Heretosis is free money
– We can design cattle to fit any environment
– To use average breed effects
– To target specific beef markets