Mapping Livestock Genomes to Improve Animal
Assembly of the
first draft of the
human genome heralded a new age in human medicine. The time it takes to
find genes related to specific traits or disease has been radically shortened,
in some cases from several decades to a few years. Animal agriculture will also
reap benefits from the Human Genome Project, as the project provides research
tools and resources previously unavailable to livestock production
Due to funding constraints, genomes of
agricultural animals will likely never be elucidated as fully as the human
genome. But commonalities between human, mouse, and livestock genomes will
allow greater understanding of how livestock genetics can be used to improve
ARS has long played a key role in the
international research on animal genomes. In 1994, researchers at ARS
Meat Animal Research Center provided the
first genetic linkage maps for cattle and swine. In 1995, ARS scientists at
Evaluation and Mapping Laboratory in Beltsville, Maryland, identified a
region on chromosome 23 where
influence a cows response to mastitis.
More than two dozen ARS scientists at eight
locations develop genetic information on livestock, poultry, or fish or
microbes that cause animal disease, such as the bacterium that causes
Johnes disease in cattle. This research benefits from access to
sequencers acquired by ARS in 1998. These DNA analyzers are helping mappers
rapidly expand their library of genetic
ARS research focuses on genes involved with
resistance and susceptibility to disease in the animals as well as the genes in
the microbes that allow them to infect and spread disease. By understanding
both the host and the disease agent, scientists should be able to find better
genetic strategies to improve animal health in the future. Information on the
microbes alone will improve diagnosis. The advantage to working with microbes
is that many have small genomes that can be completely sequenced in a short
period of time.
ARS also works on basic genetic maps, such
as the new efforts on catfish and trout, that will subsequently be used to
identify genes that influence animal health. With several international
collaborators, ARS researchers are also developing extensive libraries that
contain sections of animal genomes. These DNA libraries allow scientists to
construct a new type of physical map for livestock species that will be used to
identify potential genes that affect animal health and other production traits.
Comparisons with human and mouse genomes dramatically enhance researchers'
ability to identify the gene and determine its function.
In addition to providing long-term federal
funding to this basic research, ARS has two unique advantages for this work.
First, ARS has access to large populations of pedigreed livestock that have
been researched for many years, and a talented staff of personnel trained in
collecting production data on these animals. Second, ARS has developed
multi-disciplinary teams to conduct genomic research to address animal
For more information on ARS genetic
programs, visit ARS national program on
Animal Production or contact any of the following:
John Bannantine or
Ames, IA - microbes
Athens, GA - microbes
Beltsville, MD - pigs, chickens
MD - dairy cattle
Laegried, Clay Center, NE - cattle, pigs,
East Lansing, MI - chickens
Caird Rexroad III,
National Center for Cool and Coldwater Aquaculture, Leetown, WV - trout
Orient Point/Plum Island, NY - microbes
Stoneville, MS - catfish
Steven Kappes, National
Leland Ellis, Jr., National
diagnostic tests for
piroplasmosis , or equine babesiosis, should eventually help horse owners
ensure their animals are healthy after traveling to countries where the disease
is endemic. The tickborne disease is not present in the United States.
Cooperative research between Phelps Dodge Refining
Corp., El Paso, and ARS will determine whether copper sulfate
can protect catfish eggs from fungi.
Increased levels of the hormone adrenomedullin may
indicate infection in cattle, goats, pigs, and sheep. The ARS discovery may
lead to a test that allows producers to screen for disease stress.
Feeding cattle just before sunset can reduce aggression between
animals , ARS researchers found. Typically, cattle receive their main meal
in the morning.
Algae used in a Smithsonian/ARS-designed scrubber
system for cleaning cattle waste may provide a
supplement for cattle.
ARS-developed antibodies to
nicarbazin form the basis of a test to help protect chickens from
coccidiosis. Nicarbazin is a medication added to poultry feed. The test will
help ensure that chickens receive enough medication to keep them healthy but
not enough to leave residues in the meat.
Research on improved fescue varieties may, in the
future, protect cattle
and horses from the toxic effects of fungi that live in the fescue. ARS
scientists are also working on a vaccine.
Harley W. Moon, retired veterinary pathologist,
was inducted into the ARS Science
Hall of Fame for
diagnoses, treatments, and vaccines for intestinal diseases of
Ralph Lichtenfels, Biosystematics and
National Parasite Collection Unit, and
Jitender P. Dubey,
Parasite Biology and Epidemiology
Laboratory, shared the Distinguished Scientist Award from the Friends of
Agricultural Research- Beltsville, Inc., for outstanding research
Fadly, Avian Disease and Oncology
Laboratory, was awarded the 2000 Excellence in Poultry Disease Research by
the American Veterinary Medical Foundation.