Powerpoint presentation on the basics of beef genetics

1. Basic Beef Genetics
Tom Gallagher (CCE Albany)
Meghan Filbert (CCE Delaware)
Phil Trowbridge (Trowbridge Angus)

2. Selecting Your Next Bull
Phil Trowbridge, Trowbridge Angus Farms

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).

10. • Performance is a combination of genetics and
environment.

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

15. BW EPD, lb
+40
+16
YW EPD, lb
+80
BW EPD, lb
Bull 2
WW EPD, lb
Milk EPD, lb
Bull 1
+3
+3
WW EPD, lb
+20
Milk EPD, lb
+16
YW EPD, lb
+80

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

18. Questions?
• Resources for more information:
– trowbridgeangusfarms.com
– angus.org

19. Heterability

20. Heterosis

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

22. Designing a crossbreeding system
• Two breed rotation
• Three breed rotation

23. Criteria for Selection
• Market
– Grass fed genetics – Devon’s
– Replacement heifers
– Feed resources
– Management resources
– Farm environment
• Hills vs. flat land. Simmentals don’t like hills