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Brought to you by Kansas State University
College of Veterinary Medicine - Agricultural Practices Section
December 2006 |
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Hormone
concentrations relative to carcass composition
Carcass characteristics (HCW, 12th-rib fat thickness, KPH, LM area,
marbling score) and serum concentrations of leptin, IGF-I, and GH were
collected from cattle (n = 995 steers and 757 heifers) to evaluate
relationships between variables. Data was collected from randomly
selected animals at a commercial slaughter line on four occasions. Blood
was collected at exsanguination and carcass data was collected 24 h
postmortem. Heifers had a significantly greater (p = 0.008) leptin
concentration (11.9 ng/ml) than steers (10.9 ng/ml). Leptin
concentration was positively correlated with marbling score (r = 0.28),
12th-rib fat depth (r = 0.37), KPH (r = 0.23), and USDA yield grade (r =
0.32). Negative correlations were found between leptin and IFG-I (r =
-0.11; p < 0.001) and leptin and GH (r = -0.32; p < 0.001). A model
separating least squares means across USDA quality grade determined that
leptin concentration accounted for variation between the means. There
was no difference observed in leptin concentrations between upper 2/3
choice and prime carcasses (12.9 and 14.2 ng/ml, respectively), but
differences existed between USDA standard (8.5 ng/ml), select (10.3 ng/ml),
low choice (12.2 ng/ml), and upper 2/3 choice/prime (> 12.9 ng/ml)
carcasses. Relationships within endocrine profiles and between endocrine
concentrations and carcass quality characteristics may prove to be a
useful tool for the prediciton of beef carcass composition.
Brandt, M.M., Keisler, D.H.,
Meyer, D.L., Schmidt, T.B., and Berg, E.P. Serum hormone concentrations
relative to carcass composition of a random allotment of commercial-fed
beef cattle. J. Anim Sci. 85(1): 267-275
Voluntary National
ID Program
The USDA recently released the latest draft of the National Animal
Identification System (NAIS) user guide. This new guide replaces
previous versions and stresses that participation in the NAIS program is
voluntary for producers. There is no Federal requirement for producers
to participate in any aspect of the program. The guide states that a
mandatory program is not necessary to achieve program goals, and as
voluntary participation grows, there will be less need to make the
program mandatory.
The NAIS plan is a State-Federal-industry partnership that continues to
evolve and is still open for modifications. The guide also stated that
federal law protects participant private information and confidential
business information from disclosure.
Previous versions and communications from USDA included timelines for
100% premise and newborn animal registration (by January 2009). The
recent version did not contain a timeline for levels of voluntary
participation.
As the program is not mandatory, producers will need incentives to
account for increased costs of participation. The document lists
benefits of participation to include: a better ability to protect
premises and livelihood, better positioned for market access and
marketing opportunities, and better equipped to reduce hardships due to
animal disease events.
The NAIS user guide can be found on the web at:
http://animalid.aphis.usda.gov/nais/index.shtml
Effect of
certified health programs on sale price of beef calves
A longitudinal study of 26,502 sale lots of over 3 million head of
cattle was performed to quantify effects of certified health programs on
the sale price of beef calves sold through a livestock videotape auction
service. Data describing calves marketed from 1995 through 2005 was used
to generate multiple regression analysis to quantify effect of certified
health programs on sale price. Beef calves that qualified for the two
most rigorous certified health programs sold for significantly higher
prices in each year of the study compared to calves that were not in a
certified health program, had not been vaccinated against respiratory
tract viruses, and were not weaned before delivery. Price premiums for
calves in the most intensive certified program ranged from $2.47/cwt in
1995 to $7.91/cwt in 2004. The percentage of lots enrolled in the two
most intensive programs increased over the period of study. Thus, this
study found a premium was paid for a specific level of preconditioning
and participation in the programs increased over this 11 year period.
King, M.E., Salman, M.D., Wittum,
T.E., Odde, K.G., Seeger, J.T., Grotelueschen, D.M., Rogers, G.M.,
Quakenbush, G.A. Effect of certified health programs on the sale price
of beef calves marketed through a livestock videotape auction service
from 1995 through 2005. J. Am Vet Med Assoc 229(9): 1389-1400
Validation of
commercial DNA tests for quantitative beef quality traits
The U.S. national Beef Cattle Evaluation Consortium determined
associations between 3 commercially-available genetic marker panels (GeneSTAR
Quality Grade, GeneSTAR Tenderness, and Ingenity TenderGENE) and
quantitative beef traits. The validation was performed to provide
independent evaluation and confirmation of associations between genetic
tests and phenotypes. Quality grade validation was performed on 400
Charolais x Angus cattle, and tenderness was evaluated on over 1000 Bos
Taurus and Bos indicus cattle. The GeneSTAR Quality grade is being
marketed as a test associated with marbling and quality grade. Genotype
results from this test were not associated with marbling score in this
study, but association of substituting favorable alleles of the marker
panel with increased quality grade approached significance (p < 0.06).
The GeneSTAR Tenderness and Igenity TenderGENE marker panels are
marketed as tests associated with meat tenderness as assessed by Warner-Bratzler
shear force. Both panels had highly significant (p < 0.001) associations
with calpastatin marker and μ-calpain haplotype with tenderness.
Independent validation studies are important to help build confidence in
marker technology and also represent a source of data required to enable
the integration of marker data into genetic evaluations.
Van Eenennaam, A.L., Li, J., Thallman, R.M., Quaas, R.L., Dikeman, M.E.,
Gill, C.A., Franke, D.E., Thomas, M.G. Validation of commercial DNA
tests for quantitative beef quality traits. J. Anim Sci. published
online first 12/18/06, doi: 10.2527.
___________________________________________________________________
Beef Research News is produced by the Agricultural Practices section at
Kansas State University. To modify your subscription to this service
please email Erin Thomas (
ethomas@vet.k-state.edu )
For more information please contact:
Brad White
Beef Production Medicine
Q211 Mosier Hall
Manhattan, KS 66506
bwhite@vet.ksu.edu
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