Joining him as co-principal investigators are USDA ARS colleagues Jitender Dubey, Ph.D.; Mark Jenkins, Ph.D.; and Manan Sharma, Ph.D. Kalmia Kniel, Ph.D., with the University of Delaware, also is a co-PI.
Rosenthal pointed to Kniel and Sharma’s previous work on filtration to reduce bacterial and viral pathogens in water as basis for the current project.
“We’re evaluating the basic principle that physical exclusion might be an option to reduce parasite burdens,” Rosenthal said.
As part of proof-of-concept work, the researchers will use Eimeria as a Cyclospora surrogate. A close relative of Cyclospora, the chicken pathogen Eimeria is readily available and safe for humans to work with.
In their initial laboratory trials, they inoculated water with a known quantity of Eimeria, ran it through a PVC tube filled with sand to simulate a sand filter and measured the pathogen reduction in the outflow. Rosenthal said the results were encouraging.
But when they back-flushed their make-shift filters, they recovered about 80% of the original Eimeria population.
They repeated the experiment using a filter comprising 50% sand and 50% ZVI. They found a similar reduction in pathogens in the outflow. But when they back-flushed the ZVI medium, they detected very few Eimeria.
“We’re seeing when you have ZVI, it’s tighter holding, so I think it’s doing something physical that sand alone doesn’t do,” Rosenthal said.
To determine whether ZVI has an additional effect on the pathogen, he said they plan to swirl it in a solution of zero-valent iron and water.
“Then we can take those parasites and examine them to see if they are looking injured,” he said. “More importantly, we’ll feed them to the chickens to see if they are capable of causing infection.”
For the final test, the researchers will run Cyclospora through the ZVI filtration system to determine whether they see a population reduction similar to Eimeria.
Rosenthal said he hoped the project will provide scientific data the industry can use to make risk assessments.
“It’s certainly my hope that they might find these kinds of data helpful on practical applications as a means to reduce or manage risk,” he said. “We’re here to understand and try to address real problems for our stakeholders.”