How can you keep pathogens out of your feed mill?
In addressing feed safety issues, there are five questions that should be answered, according to Chad Paulk, assistant professor in grain science and industry at Kansas State University (KSU), who spoke November 19 during the 2020 KSU Swine Day.
“Feed is just one of the many potential vectors of pathogens,” he said. “Some of the key things we can do is exclude high-risk ingredients from high-risk countries, improve our supplier communications, … creating that culture around biosecurity within your feed mill … and consider feed and environmental testing to learn more.”
Paulk said the following steps should be taken to mitigate the risk of pathogens in feed.
Is it likely to get infected?
First, one must determine whether the ingredient or complete feed is likely to be infected with a pathogen.
“What determines that risk? When we’re thinking about risk of pathogens contaminating ingredients, what do we need to be thinking about?” Paulk asked.
He said the geographical location of the ingredient’s origination needs to be determined, and then find out if there is a pathogen or disease outbreak in that region that could contaminate ingredients. If there is, then find out what the agricultural practices are in that area that could spread the pathogen, or whether there are practices that can mitigate risk.
Can it survive?
Research has shown that ingredients that tend to harbor viruses have a higher protein content, such as soybean meal, Paulk said.
“There’s a lot of different pathogens that act differently or survive for different lengths of time in different ingredients, so it’s really something you have to take on a case-by-case basis to understand what pathogen you’re dealing with, what ingredient you’re dealing with and what their survival rate’s going to be,” he said.
Is it infectious?
What kind of virus is present and how much of it can have an effect on its infectiousness.
“When we’re trying to determine if it’s infectious, it’s going to depend on the virus, it’s going to depend on how much virus is needed for the animal to get infected,” he said.
How can it be prevented?
Through research, Paulk said he has learned that the main sources of contamination in the feed mill are trucks or people. He said there are things that can be done to prevent trucks with dirty tires and people with dirty shoes from entering the feed mill.
“What kind of practices are we incorporating at the feed mill or what can we improve upon to potentially prevent bringing that virus in?” he asked. “Our goal is to eliminate contamination from trucks or people.”
Some practices can prevent contamination in the feed mill. Receiving mats or funnels should be used to keep feed ingredients from contacting dirty surfaces, drivers should stay in their trucks, and there should be an employee culture that is focused on biosecurity.
How can it be mitigated?
Feed mitigants can be used to provide another level of protection against viral contaminants, but not all mitigants work the same with all viruses.
“If we’re not able to prevent (contamination) or we want an added layer of risk reduction, there are potential feed mitigants that can be added,” Paulk said. “But the one thing we have to consider is, as you look at different viruses, they have different properties about them and mitigants are going to act in different ways.”
Another consideration when choosing a mitigant is the surface type where contamination could occur, such as cement, plastic, rubber, stainless steel and tote bags.
“When we think about moving feed through a feed mill, all of our different surfaces and how dust collects on those surfaces and the ability to survive,” he said.