COLUMBUS, Ohio Tiny mites living on the surface of Madagascar hissing cockroaches help decrease the presence of a variety of molds on the cockroaches' bodies, potentially reducing allergic responses among humans who handle the popular insects, according to new research.
Scientists cultured and identified fungi on the cockroaches' body surfaces with and without mites and discovered that the presence of these mites reduced the molds by at least 50 percent.
Many of these same researchers reported a year ago that 14 different types of mold were present on and around this species of cockroach, including several fungi associated with allergies and others that can cause secondary infections if they enter the lungs or an open wound.
The mites eat saliva and organic debris that collects between the cockroaches' legs, eliminating material that would foster mold growth on the insects' bodies. The mites don't appear to actually eat any mold.
"We haven't proved yet that this helps the cockroaches, but reducing the fungi present on their surface is beneficial overall," said Joshua Benoit, a doctoral student in entomology at Ohio State University and a co-author of the study. "By suppressing the molds, the mites have a role in reducing allergic reactions to cockroaches."
The research is published in the current issue of the journal Symbiosis.
he Madagascar hissing cockroach, or Gromphadorhina portentosa, grows to between 2 and 3 inches long and 1 inch wide, and makes its characteristic hissing sound if it is squeezed or otherwise feels threatened. Its gentle nature, large size, odd sounds and low-maintenance care have made the species a popular educational tool and pet for years.
When Benoit and colleagues discovered the molds on cockroach surfaces in a previous study, they recommended that people wash their hands after handling the cockroaches and emphasized the need to keep the insects' cages clean. Be
|Contact: Joshua Benoit|
Ohio State University