"The biggest challenge is determining the correct
types and quantity of probiotics because of the numbers and diversity
of microbes and the poorly understood interactions between the microbes
and the intestine," Donoghue says.
So far the team has screened more than 4 million enteric
isolates to come up with several promising probiotic combinations. The
University of Arkansas and ARS have filed a patent on the selection
A Test To Identify Probiotics
"By using these preselected good microbes, we hope to produce
inexpensive, defined cultures with the ability to reduce or exclude
specific pathogens and enhance enteric health in poultry," Donoghue
says. "We've developed multiple in vitro selection systems for
identification of candidate organisms."
When they find potential probiotics, the researchers test and identify
the individual microbes in their labs and send them to the Arkansas
Livestock and Poultry Commission's diagnostic laboratory in Springdale
as a backup check. They also test these individual isolates to eliminate
potentially harmful microflora by injecting them into turkeys and chickens
and evaluating these birds for lesions and rates of disease and death.
Donoghue says the organisms they are selecting are very easy to propagate
in batch culture, using inexpensive growth media. These bacteria are
all facultative aerobes, meaning that they are oxygen tolerant. Producing
such organisms on a commercial scale is expected to be much less expensive
than some cultures that include strict anaerobes requiring complex equipment
This new method makes it much less expensive to produce probiotics.
This could both lower the price of poultry and make it less likely to
be a source of foodborne illnesses.By Jim
Core, Agricultural Research Service Information Staff.
This research is part of Food Safety (Animal and Plant Products),
an ARS National Program (#108) described on the World Wide Web at www.nps.ars.usda.gov.
Annie Donoghue is in the
USDA-ARS Poultry Production
and Product Safety Research Unit, Center of Excellence for Poultry
Science, University of Arkansas, Fayetteville, AR 72701; phone (479)
575-2413, fax (479) 575-4202.
Collaborations such as the Poultry Production and Product Safety Research
Unit's partnership with the University of Arkansas and Mexican scientists
to gain new insights into use of beneficial bacteria in poultry wouldn't
be possible without support from the ARS Office of International Research
Many ARS research projects are designed to tackle problems that have
impacts felt around the world. OIRP helps ARS researchers conduct research
in nations where mutual interests exist in areas including animal health,
biotechnology and biosafety, protection of crop health and pest control,
food safety, and water and environmental conservation.
With guidance from OIRP, ARS researchers throughout the United States
and overseas are collaborating with scientists from several nations,
including Brazil, Israel, and countries of the former Soviet Union.
Besides investigating food safety, Mexican counterparts are collaborating
on several projects.
For example, ARS researchers in Kerrville, Texas, are working with
scientists from Mexico's National Research Institute of Forestry and
Agriculture (INIFAP) in Cuernavaca, Morelos, to determine the nature
and scope of resistance in southern cattle ticks and horn flies to pyrethroid
and organophosphate pesticides. Their work includes developing practical
guidelines to manage this resistance and protect livestock. They hope
to create assays to monitor such resistance.
In another joint project, Mexican scientists in the Toluca Valley are
screening potato genotypes that ARS scientists are developing for resistance
to late blight (Phytopthora infestans), the most important potato
disease worldwide. Since all known strains of late blight have occurred
in the Toluca Valley, this cooperation is imperative if new varieties
are to resist potential future strains.
Eileen Herrera is an international affairs specialist with OIRP. She
indicates that many projects focus on issues that affect productivity,
trade between the United States and Mexico, and natural resources management
along our shared border. She says OIRP recently completed a pilot program
to exchange graduate students and postdoctoral researchers between Mexico
and the United States. She said the program not only increased cooperation
between the neighboring nations, but it also had the added benefit of
improving professional development within ARS, since the program emphasized
participation from the agency's early-career scientists.
Herrera says the latest direction in their relationship with Mexican
research institutions was to increase and enhance cooperation through
a series of five workshops, in partnership with INIFAP, ARS's counterpart
agency in Mexico. "The workshops are a mechanism for a more strategic
approach to cooperation between ARS and Mexican research institutions,"
Herrera says. "My hope is that within the next few years, we will
take what has already been a productive relationship between scientists
and their respective research locations and build on it to make it more
comprehensive at the agency level."By Jim
Core, Agricultural Research Service Information Staff.
is with the USDA-ARS Office of International Research Programs, 2000
East Allen Rd., Tucson, AZ 85719; phone (520) 670-6380, ext. 120, fax
Good for People
Probiotics are good for people, too. All animals have naturally occurring
beneficial probiotics in their guts. One commonly known probiotic, Lactobacillus
acidophilus, is naturally present in foods such as yogurt, grains,
and meat products. And prebiotics such as inulin have been used extensivelyparticularly
in Europe and Japan where they're now included in many food products
from sports drinks to baby formula.
"Probiotics Protect Poultry From Pathogens" was published
in the January
2004 issue of Agricultural Research magazine.