Meeting the Challenges of Keeping Aquatic
Among agriculturally important animals, fish
pose unique challenges for maintaining health. More than 50 diseases affect
fish and shellfish cultured in the United States, and managing diseases and
parasites is one of the industrys highest priorities. ARS supports about
two dozen scientists in three main laboratories that work together to support
ARS researchers study how fish transmit and
contract disease in their watery surroundings. For example, current research
bacterium Streptococcus iniae likely enters the fishes nostrils
through the water. Also, parasitic worms that can infect fish can pass from
birds who feed on the fish into the ponds. The worms then develop in aquatic
snails, then enter the fish.
Understanding such complex relationships
helps scientists devise the best approach to disease control. Much of the work
at ARS Aquatic Animal Health Research
Laboratory in Auburn, Alabama, focuses on vaccine development.
vaccine for S. iniae reduced mortality in tilapia and hybrid striped
bass by more than 80 percent in the laboratory. Another recent success was the
first approved modified
live-bacterium fish vaccine to protect young channel catfish from enteric
The Auburn staff works closely with
geneticists in Stoneville, Mississippi, to
improve fishes natural ability to resist disease. To date, genetic
improvement in agriculture has focused on livestock, poultry, and crops. Now
ARS researchers hope to bring both traditional breeding and molecular biology
to bear on disease management in aquatic systems.
ARS has a long history of helping fish
farmers deal with parasites. Researchers in Stuttgart, Arkansas, conduct experiments to
support regulatory approval of compounds such as copper sulfate and potassium
permanganate that can be added to the water to reduce parasites. Thats
important because few chemicals are approved to treat diseases and parasites.
Water-based treatments are often more effective because ill fish dont
eat, so medication cant be delivered effectively through food.
Other research projects include developing
diagnostic tests for important diseases, characterizing the fish immune system,
and improving nutrition for cultured aquatic animals.
For more information, visit the
site describing this national program.
Or contact any of the following:
Klesius, Auburn, AL
William Wolters, Stoneville,
Growth charts of
sunshine bass and zooplankton developed by ARS scientists help
aquaculturists protect their fish by stocking them at a precise time when they
can grow fast and not become prey to the zooplankton.
Gerald M. Ludwig
To improve piglet health and growth after weaning,
ARS researchers are comparing the immune
system responses of piglets fed spray-dried plasma to those without the
supplemental protein. Piglets fed the plasma showed evidence of being better
able to resist infections.
Jeffery A. Carroll
The first animal model to
study tuberculosis spread in white-tailed deer, developed by ARS
scientists, has allowed researchers to find that deer saliva, nasal secretions,
urine, and feces contain the disease organism. Thats helping them define
how infected deer spread TB and should help eradication efforts.
Diana L. Whipple
A new, ARS-designed
reduced Salmonella by 94 percent in a commercial poultry
Insectary leftovers make
nutritious cattle feed, ARS and University of Hawaii scientists found. The
mix, based on wheat germ or corn cobs, is originally used to raise sterile
fruit flies for insect control programs.
Eric. B. Jang
ARS laboratory experiments showed that
sodium carbonate kills
E-coli and other harmful microbes in cow manure. This finding could lead
to a cost-effective way to improve livestock and human health.
James B. Russell
Entomologist Edward F.
Knipling died March 17 at his home. Knipling pioneered the sterile male
insect technique that led to eradication of the wild screwworm population in
the United States, Mexico and parts of Central America.
These ARS researchers have been honored recently
for their achievements:
ARS Scientist of the Year
Technology Transfer Awards:
Klesius, Aquatic Animal Health Research
Laboratory, for outstanding research to improve the health of farm-raised
Ann M. Donoghue,
Germplasm and Gamete
Physiology Laboratory, for significant contributions in understanding
turkey sperm function, physiology, preservation, and quality.
Craig A. Shoemaker and
Phillip H. Klesius,
Aquatic Animal Health Research Laboratory, for a
modified live vaccine to protect channel catfish from enteric septicemia.
Katherine I. ORourke
and Donald P. Knowles, Jr.,
Animal Disease Research Unit, for diagnostic
tests to detect scrapie in live animals, piroplasmosis in horses, and
anaplasmosis in cattle.
Mitchell, Southeast Poultry Research
Laboratory, for an electrostatic space charge system to reduce airborne
dust and disease-causing microorganisms in poultry houses.
Bellows, Ft. Keogh Livestock and Range Research
Laboratory, named Outstanding Agricultural Leader of Montana by Montana
State University for exceptional research contributions in beef cattle
physiology and reproduction.
P. Hoberg, , Biosystematics and National
Parasite Collection Unit, appointed Museum Affiliate to the University of
Alaskas Mammalogy Department.
Carroll, Robert L. Matteri,
Cheryl J. Dyer,
Animal Physiology Research Unit, awarded the
National Pork Producers 2000 Award for Innovative Basic Research.