ARS researchers have found that the microbes in
manure can play an important role in breaking down antibiotics and other
pharmaceuticals excreted by treated livestock. Click the image for more
information about it. |
Microbes in Manure Can Minimize Potential
Pharmaceutical Pollution
By
Erin Peabody January 27, 2006
Bacteria are usually viewed as the enemy and targeted with
potent antibiotics to curb their ability to cause infection. But according to
Agricultural Research Service (ARS)
scientists, microbes--including several types of bacteria--can be a
farmers ally when it comes to reducing the risk that
antibiotic-containing manure may pose to the environment.
Livestock and poultry producers rely on antibiotics to treat a host of
diseases and infections. In fact, more than 21 million pounds of antibiotics
were administered to U.S. farm animals and pets in 2004. Such treatments help
promote animals health and well-being, in addition to ensuring a safe
food supply for consumers.
The trouble is, when animals excrete in their waste antibiotics and
other pharmaceuticals that their bodies dont use, the compounds may
linger in the environment. This so-called pharmaceutical pollution can
encourage bacteria to mutate and form strains that are resistant to current
antibiotics.
Scott
Yates, a soil scientist with ARS
George
E. Brown, Jr. Salinity Laboratory in Riverside, Calif., wanted to find out
what happens to antibiotic-laced manure once its mixed with soil, as
typically happens when livestock manure is spread onto farm fields as a
fertilizer.
Yates and colleague Qiquan Wang studied one commonly administered
veterinary antibiotic, sulfadimethoxine, which is used to combat a number of
diseases in livestock and pets.
They developed a mathematical model which revealed that thriving
manure microbes play an important role in determining how quickly
sulfadimethoxine degrades. Some microbes in manure can digest and inactivate
the excreted antibiotic.
According to Yates and Wang, farmers should try to create a hospitable
environment for these tiny helpers. They should store waste from treated
animals in a warm, moist place for as long as possible before spreading it onto
fields. This gives the beneficial soil microbes an opportunity to act on an
antibiotic, before it has the chance to leach into soils and waterways.
ARS is the U.S. Department of
Agricultures chief scientific research agency.