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Healthy Animals 40

Germplasm Collection is Key to Ensuring Healthy
Animals

Research Briefs
More milk, less
calves. ARS scientists have discovered why Holsteinsbred to
produce more milkare less fertile than before breeding efforts were
stepped up to increase dairy production.
Cleaner
chicken. Technology developed by ARS researchers that automatically
scans poultry carcasses for contamination has been successfully tested in a
commercial poultry plant.
Easier for
ewes. Artificial insemination techniques that work well with cattle and
swine can be difficult or costly to perform in sheep, but help's on the way,
thanks to ARS studies.
Better blood
flow. Doppler technologythe very same technology used by
meteorologists to track thunderstormsis being used by ARS scientists to
better understand the rate at which fescue toxicosis restricts blood flow in
cattle.
Thwarting E.
coli. Immunizing calves with either of two forms of a vaccine newly
developed by ARS researchers might reduce the spread of sometimes deadly
Escherichia coli O157:H7 bacteria.
Hitchhiking
bugs. Plywood-shelved carts that are used to transport eggs into
processing plants can harbor Enterobacteriaceae, according to a
microbial survey conducted by ARS scientists.
Sterile
screwworms. Transgenic screwworms developed by ARS researchers could
set the stage for new, improved methods of eradicating the pest based on the
sterile insect technique.
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It was a modest enough beginning a decade ago, when researchers from the
National Animal Germplasm Program (NAGP) began stashing away genetic material
from 40 distinct lines of chickens. Those birds have become the foundation of
one of the worlds great germplasm repositories, which now houses half a
million samples from 12,000 animals.
The collection of germplasm at the Fort Collins, Colo., facility maintained
by the Agricultural Research Service (ARS) assures a future with genetic
diversity of agriculturally significant animalsespecially dairy and beef
cattle, chickens, sheep, swine and even bison, elk and fish.
As we learn more about genes and gene function, it becomes not only a
backstop for the industry, but a tool for the research community, says
Harvey Blackburn, NAGP coordinator. With a genetic resources collection
like we have here, the more thats known about gene function, the more
important it becomes.
Providing vital genetic material for scientific research has become a
primary function for Blackburn and other NAGP specialists at the Colorado
facility. They have distributed 2,500 animal samples to ARS researchers,
private laboratories and university scientists who are working to improve the
genetic makeup of animals.
The collection has been useful in many ways. For example, ARS researchers
have used frozen bull semen to genotype prominent bulls that have sired dairy
cattle. This information, combined with milk production comparison data
gathered from the cows, has been used to improve dairy cattle breeding
programs.
Genetic material also has been used to restore breeds of cattle and other
animals that have died out. Researchers insist that maintaining diversity by
preserving germplasm--even if the material comes from breeds that arent
currently being studiedacts as an insurance policy against future
diseases or other threats.
In many cases, the storage chest at NAGP has saved money for animal
producers, who have begun using semen samples preserved at deep-freeze
temperatures, rather than keep a live herd of cows or other animals, which are
costly and time-consuming.
ARS researchers in Miles City, Montana, store and use their cattle germplasm
to help their efforts to reduce beef production costs, as demand for corn grows
with the need for ethanol and human food. Young female cattle, for instance,
can be bred for lower target weights, consuming 27 percent less feed over the
winter. The program might reduce costs of each replacement heifer by more than
$31.
The germplasm collections provide information as well as breeding material
for animal producers, and they play an important role in protecting and
improving agricultural livestock.
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National Animal Germplasm Program coordinator Harvey Blackburn
and technician Ginny Schmit place germplasm samples into a liquid nitrogen tank
for long-term storage.
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In Florida, ARS scientists are working to save cattle breeds that are
tolerant of tropical temperatures by studying the cattle genome and storing and
preserving the germplasm they need for that research. The Subtropical
Agricultural Research Station in Brooksville is a satellite repository that
also supplies genetic material to ARS in Colorado.
The NAGP collection has been used to prevent existing breeds from dying out.
Scientists there collected and distributed germplasm to support milking
Shorthorn cattle, a rare breed whose numbers are unknown in the United States.
The Shorthorns have lower milk yields than Holstein or Jersey cattle, but have
been successfully crossbred with other breeds. They also are valued for their
even temper and production efficiency. NAGP researchers have helped collect
genetic material from animals that have been verified as native Shorthorns.
In related work, scientists at the ARS National Sedimentation Laboratory
(NLS) in Oxford, Miss., have been cataloging 124 species of fish, amphibians,
reptiles and mammals to build a baseline sampling of animal diversity,
including about 11,000 samples taken since 1986. During those efforts,
scientists documented the presence of one rare species, the Yazoo darter, a
fish found only in fresh water and ponds near Oxford.
Researchers there maintain the collection of 11,000 specimens mostly for
identification purposes, or to document the arrival of the occasional rare
species, said Scott Knight, who works at the NSLs water quality and
ecology research unit. In 2001, University of Southern Mississippi
ichthyologist Stephen T. Ross published a 624-page book about the inland fishes
in the Deep South.
In Michigan, researchers worked with DNA-based technology to develop 40
distinct lines of chickens at the Avian Disease and Oncology Laboratory (ADOL)
in East Lansing. Those studies have revealed tools and techniques used in the
diagnosis, control and prevention of diseases such as virus-induced tumors in
poultry. The unique and genetically well-defined lines have been critical to
significant research projects at ADOL and at similar laboratories in the United
States and overseas, and have increased understanding about genetic resistance
to disease.
The ARS U.S. Meat Animal Research Center in Clay Center, Neb., has evaluated
more than 50 cattle breeds, selection lines, and crossbred cattle populations
since its inception in the 1960s. Dozens of sheep and swine breeds, crossbred
populations, and selection lines have also been evaluated.
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Information from this research has a significant influence on the types of
animals being produced in the industry. A byproduct of the research has been
the accumulation of diverse and influential genetic material. This genetic
material has been invaluable for finding and verifying genetic markers
associated with meat tenderness, prolificacy, muscling, and other measures of
production efficiency. The research station is also a satellite repository and
supplies genetic material to the Colorado collection.
For more information about ARS germplasm collections, contact
Mark
Boggess, leader of ARS National Program #101, Food Animal Production.
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