Feed Ingredients and the Threat of Foreign Animal Disease

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With African Swine Fever in other parts of the world, there is renewed focus on the prevention of foreign animal diseases. One way to reduce the possibility of disease transmission is to know how long certain feed ingredients have been stored before allowing their use on pig farms. Dr. David Pyburn, Senior Vice President of Science and Technology, National Pork Board, outlines this peer-reviewed research and the strategies for pig farmers.


Don Wick


Dave Pyburn, Senior Vice President of Science and Technology, National Pork Board




Don Wick: 00:00 From the Pork Checkoff in Des Moines, Iowa, it’s Pork Pod. Pork Pod, a look at the hot topics in today’s pork industry. The Pork Checkoff is working for you through various forms of research, promotion, and consumer information projects. I’m Don Wick speaking on behalf of the Pork Checkoff. And today our guest is Dr. David Pyburn, who is the senior vice president of science and technology with the National Pork Board. And certainly as we take a look at the issue of African Swine Fever, it has brought renewed focus to some research that has been done on feed ingredients. Dr. Pyburn, refresh our memory if you would, tell us a bit more about this particular piece of Pork Checkoff funded research.

Dr. Dave Pyburn: 00:39 Remember, the reason we were doing this study and the reason it’s already done before we’ve had this African Swine Fever expansion of territory, if you will in eastern Europe, western Europe, Belgium, and also in China. But the recent, the reason this work was already done that we have this in the can is, is because of PED. And, uh, we were pretty well convinced that PED likely came to us either in a feed ingredient or on feed tote. Likely came to us from these regions, one of these regions in China that has experienced African Swine Fever Virus right now. So, Scott Dee up at Pipestone, put together some research looking at as best he could, the big three foreign animal diseases. Looking at the capability for feed to transport those viruses here. And once they got here and got put in front of our pigs, they have those viruses still alive.

Dr. Dave Pyburn: 01:36 So, he looked actually at African Swine Fever Virus. He used that virus, he used a surrogate viruses for Classical Swine Fever and for Foot and Mouth Disease because he couldn’t actually use the real viruses in those cases. But the work was done with African Swine Fever and he looked at those feed stuff that we are purchasing and bringing them in from China. So things like amino acid minerals, in some cases soybean oil, soybean cake, and some other items as well, vitamins as well. And, uh, when he did that, what he found was that in fact CSF is not likely to survive, at least based on his one study, CSF is not likely to survive that transport across the ocean to get here to the United States, but in both cases for FMD, Foot and Mouth Disease and also for African Swine Fever, it’s, it very well could survive in those feed stuffs and come here to the United States in those feed stuffs, um, feed stuffs that range from, as I said, the amino acids, vitamins, minerals, and the soybean oil, soybean meal as well.

Don Wick: 02:41 So knowing that, what should a pig farmer today do to make sure that we’re not seeing the situation?

Dr. Dave Pyburn: 02:50 Well, I think the number one thing they can do is to talk with their feed supplier and try to determine upfront of the different ingredients that I have in my feed, the different components that are in my feed. Where do they come from and do they come from some countries that have African Swine Fever, China being one of them. But we also get feed stuffs from other areas as well. Determine that first. Then determine if it is made in a country where African Swine Fever or any of the three foreign animal diseases are known to be active. Then are they produced in a bio secure manner and those countries. Ask your feed supplier if they know. That they may not know it, but it would be something that should be discoverable as to how they’re produced in those countries.

Dr. Dave Pyburn: 03:32 If you can’t figure out whether they’re produced a bio secure manner or in a bio secure facility in those countries, then I think you have to assume that there could be some risk here of putting these viruses in front of our pigs in feed. So then your choice is am I willing to accept that risk as is? Do I want to do something to mitigate that risk or do I want to consider maybe trying to find another source for any of those components that come from African Swine Fever or any of the foreign animal disease positive countries.

Don Wick: 04:03 Obviously when you’re making that feed decision or purchasing your feed ingredient, sometimes it doesn’t come top of mind, so does this take a little bit of homework or what do you find dealing with most of these feed companies?

Dr. Dave Pyburn: 04:14 Yeah, and so we understand that this is not a normal conversation that producers are used to having with their feed suppliers and the companies that sell them feed components, but I would say it’s one we need to start getting used to and we need to be able to have these discussions. And I think it goes beyond what we’re dealing with today. We’ve got heightened alert today because of African Swine Fever. We had a heightened alert three to four years ago because of PED, but I think we need to stay on top of this stuff around the clock now because China, some of these other countries they’ve had FMD, they’ve had Classical Swine Fever for a number of years. We maybe should have gotten this done a lot sooner, so it’s a discussion that we want producers to start getting comfortable having with their feed suppliers.

Dr. Dave Pyburn: 04:56 We want feed suppliers to start getting comfortable either answering these questions or discovering the answers to these questions and to that end up on our website at www.pork.org/FAD.. We’ve got a document there, a disease risk matrix document that leads you through what I’ve just talked about, looking at your feed components. Are they safe, are they done in a secure facility? Those kinds of questions. And then on the backside of that document we’ve got the discussion points that lead you through that discussion with your feed supplier so that you know the questions or you can walk in or deliver the questions ahead of time to your feed supplier and you can get some answers to some of these questions you’ve got as far as the bio security of your feed.

Don Wick: 05:41 In addition to the feed stuff Dave, I’m curious just when we look at how mobile our society is today and people travel worldwide, how big of a concern is some of these travel considerations when we’re looking at some of these very contagious diseases?

Dr. Dave Pyburn: 05:55 Well in some cases, some the countries that have gotten this virus they’re not sure exactly how they got the virus into the country, but that’s speculated to be a high possibility suspect as far as how the virus got into their country is through tourism, through travel, between countries, through the hauling of illegal, in most cases, illegal feed stuffs between countries. We’ve got to get the public to also understand that our food structure basically is at risk here from some of these diseases, from any of these diseases. And thus don’t be bringing back illegal materials from countries that you visit. When you go through quarantine as you return from foreign countries, declare everything you’ve got that could be a risk material. They list out on that blue form that they give you. Be sure to declare everything and only bring in what they say is safe. We’ve got to watch for this because the UK for example, and this goes back about 20 years ago now, but the UK is fairly well convinced that the last time they had Classical Swine Fever, it probably came in a sandwich that was discarded and then consumed by a pig.

Don Wick: 07:04 Wow It’s pretty amazing. Anything we are missing Dave that we should focus on?

Dr. Dave Pyburn: 07:08 Yeah, ask me about holding time.

Don Wick: 07:11 So when we think about some of these feed ingredients talk to me, David, about holding time, what should they keep in mind?

Dr. Dave Pyburn: 07:19 So this goes back to that Pipestone Scott Dee research that we talked about and as we looked at, producers wanted some answers and rightfully so, they wanted some answers. They want action that they can take to hopefully make their feed more secure here on this end, even after it’s been received here or their feed components make them safer. And so we looked at Scott Dee’s research. Again, I want to stress one study and we’ve only got a couple of data points here as far as determining how quickly these viruses degrade over time in these feed stuff or feed components. But we took a look at that and we figured out what it’s something which is called half life for the virus. What that means is that’s the total amount of time that takes 50% of all the virus in a substrate to die.

Dr. Dave Pyburn: 08:04 So you get one after one half life of virus. You got 50 percent of the virus left after two half lives of the virus. You have 25 percent of the half life or a 25 percent of the virus left. You can see where I’m going here. You just keep halving your total amount of virus in whatever substrate you’re talking about. So we took a look at those feed components that Scott studied and we drew basically a line through the data points that he had and we figured out what the half life was for African Swine Fever and also for the surrogate for Foot and Mouth Disease. And by doing that, we determined that that really when you’re looking at both of them, the half life in total number of days is six. Okay? So that’s six days to get 50 percent of whatever amount of virus you have in these substrates to degrade to the point where only 50 percent is left.

Dr. Dave Pyburn: 08:54 Okay? So when you do that and you do the math, if you keep dividing and half after 13 half lives, you’re down to where 99.99% of that original virus is gone. It’s degraded, it’s dead. So you’ve got a very small amount that’s there with half lives. When you’re dividing by a half each time, you will never get to absolute zero, but you can get down pretty close. And 99.99% is pretty close. So with that we said, okay, it takes 13 half lives to get down to where you’ve only got .01% of the virus left. And so six days is the half life for both Seneca Valley and for African Swine Fever in the mineral amino acid, a feed components. So take 13 times six, you get 78. That’s where we came up with the 78 days of hold time to get viral degradation down to 99.99% of the virus gone.

Dr. Dave Pyburn: 09:55 And so that’s what you’ve seen us put out as far as the holding time calculation for feed ingredients for those producers that want to reduce their risks. Again, one study, one study that was not done at multiple temperatures, one study that was not done with multiple virus amounts, it was a study that wasn’t done with other organic or biological material in there such as urine or feces or blood. So there’s, there’s a lot of variables here that weren’t looked at. But today that’s the best science we’ve got when we start looking at how quickly these viruses will degrade in feed components. So that’s 78 days and that’s 78 days when you’re looking at amino acids, minerals, and vitamins. That doesn’t hold for all feed components. We also looked at, we looked at the soybean meal. Soybean meal, the half life was 22 days. You take 22 times 13 and you come up with 286. So that means that 99.99% of the virus in soybean meal will be gone after 286 days. In all likelihood, nobody’s going to hold soybean meal for that many days. So it may be that if you’re getting soybean meal or soy oil cake or something like that from a country that has these viruses, maybe the best thing for you to do is consider getting that somewhere else.

Don Wick: 11:11 When you talk about this holding time Dave, is that on the farm or is that the feed manufacturer?

Dr. Dave Pyburn: 11:14 You know, the best place for this is going to be actually well before that because think about it wherever we, when we bring in these components and we’re really looking at feed components, not whole feed, we’re looking at brought in Coleen, Lysine, the vitamins we use, other amino acids that we use, the minerals that we use. When you think about that, that gets mixed in a mill. So that touches all kinds of equipment in a mill. Well, you really ended that whole time to happen before it goes into the mill or you end up contaminating that feed mill. So really what we need to do is have producers, feed suppliers, be talking to people that are manufacturing this stuff about hold time. Hold it either in country where it’s produced, hold it once it hits the port, hold it once it hits a warehouse before it actually comes out of the sealed bag so that we’re not contaminating things here ahead of time, if you see what I mean.

Don Wick: 12:04 Thanks to you for listening to this edition of Pork Pod. For more information on this topic, visit pork.org.