Imported feed ingredients: Supplier’s sourcing, biosecurity, shipping vital to product integrity, safety
Kevin Eggers, DVM, technical services veterinarian at Zoetis, recently talked with editors of Pig Health Today about African swine fever (ASF) and the possible risks of importing the virus through feed ingredients — including medicated feed additives used for managing swine disease.
ASF and feed ingredients
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Q: Research has shown that ASF virus can survive for weeks or months in certain livestock-feed ingredients, even after transoceanic crossings.1 With so many vitamins and other feed ingredients imported from China, does the prevalence of ASF in that country pose a risk to US pork production?
KE: Never say never, but the American Feed Industry Association, National Pork Producers Council (NPPC), National Pork Board (NPB), Swine Health Information Center (SHIC) and American Association of Swine Veterinarians (AASV) are working — together and with government officials — to minimize that risk. It’s important to note that while three variants of coronavirus (PEDV, PEDV InDel and PDCoV) and Senecavirus A have entered the US since 2013,2 we can’t say with certainty that imported feedstuffs acted as fomites for these pathogens.3
Q: So, where do the risks for virus contamination lie?
KE: It’s not only about where a feed ingredient is manufactured or blended. The level of risk varies with the way feed ingredients are sourced, handled, manufactured and transported. It also hinges on the flow of the products and what protections are in place throughout the manufacturing and distribution chain. In the end, it’s more about the integrity and reputation of the manufacturer and the ability to create and maintain biosecure production and supply channels.
Kevin Eggers, DVM, technical services veterinarian, Zoetis
Q: What imported feedstuffs have the most potential for transmitting ASF?
KE: Research with Senecavirus A, which has been shown to be more stable than the ASF virus, indicates a higher rate of survival in raw soybean meal, choline, alternative pet-food ingredients and any products with porcine-based ingredients.4
Zoetis feed medications from China
Q: Zoetis is a leading supplier of medicated feed additives for the US pork industry. Are any of Zoetis’ swine feed medications made in China?
KE: Yes, Zoetis has several Type A Medicated Articles for swine with origins in China: Aureomycin® 90 and Aureomycin®100 Granular, Aureomycin® 90 Meal, Aureomycin® 50 Granular and Aureomix® S 40/40 Granular, ChlorMax® 50, Lincomix® 20 and Lincomix® 50.
Our Lincomix products, which contain lincomycin, are made entirely at our modern plant in Suzhou, China, and then exported to the US and other markets. It’s important to note that Lincomix is the only US Type A Medicated Article with an approved Mycoplasma hyopneumoniae claim, so it’s an important tool to use in integrated control and elimination programs involving vaccines, injectable antibiotics and other management practices recommended by veterinarians.
The API, or active pharmaceutical ingredients, for sulfamethazine (SMZ) and some chlortetracycline (CTC) products used in the US are also produced in China and obtained from sources that meet Zoetis’ rigid manufacturing standards.
Q: Are any of their inert or excipient ingredients in Zoetis feed medications from China potential carriers of the ASF virus?
KE: The excipients used in the CTC products (both the single and combination Type A Medicated Articles) include mineral oil, rice hulls, calcium sulfate and/or calcium carbonate. All of these ingredients are US-sourced and are considered minor risks for virus transmission.
Our Lincomix products are made with soybean hulls produced in the Americas and processed in China. Soybean hulls are considered moderate risks for virus transmission, but we have many processes in place to safeguard our products from contamination.
Soybean hulls versus meal
Q: If the soybeans hulls used in Lincomix are sourced from China, isn’t that a red flag for users of the product?
KE: Not at all. Lincomix is made from soybean hulls from conventional soybeans sourced in the US and Brazil and processed in China. The soybean hulls are then milled using a dedicated Zoetis supplier that processes the hulls in a closed facility before they are shipped in a closed, dedicated truck to the Zoetis-owned Lincomix plant in China. What’s more, all drivers are dedicated to Zoetis shipments. They’re not contractors who do loads for other manufacturers. As a result, there is little risk of virus contamination.
Q: Even with dedicated trucks and drivers, aren’t there opportunities for the soybean hulls or other ingredients to pick up the ASF virus on the way to the plant?
KE: The chances are slim. We maintain a strict, closed, unidirectional flow of all materials, equipment and people. That means once the ingredients are in our system, they flow in only one direction with elevated biosecurity along the way. The people and the equipment handling them also maintain a unidirectional flow, which greatly reduces the chance of contamination from people or equipment.
Q: Are the soybean hulls quarantined before they enter the Lincomix plant?
KE: The soybean hulls — that is, the outer skin of the soybean — are shipped directly from the processing plant to the miller, and then to the Zoetis plant in China. The soybean hulls are then stored in dedicated, sealed silos and used shortly after delivery.
Recommended hold times
Q: Zoetis recently announced that any feed medications containing soy materials — in this case, Lincomix — that are produced in China would not be shipped to US feed mills for a minimum of 135 days after the “born-on” date of the product or ingredient. What constitutes a “born-on date”? And why 135 days?
KE: The born-on date is when the finished product is either bagged or sealed in a container to help prevent the risk of contamination.
In December 2019, new research from Kansas State University identified increased ASF survival times in soy feed ingredients during transoceanic shipping.5 In February 2020, new feed hold-time recommendations were published and supported by the NPB, NPPC, AASV and SHIC, along with 30 of the largest state pork producer associations, which set a conventional soybean meal target at 125 days.6
In response, Zoetis reevaluated its supply chain biosecurity and solicited feedback from both large producers and members of its Medicated Feed Additive Council, which includes veterinarians and feed industry consultants. In alignment with the US pork industry, Zoetis then implemented procedures to increase product hold time to 135 days, 10 days more than the minimum.
Our 135-day hold time aligns with the responsible import guidelines supported by the majority of the US pork industry, including the NPB, NPPC, AASV and SHIC.
Q: For added peace of mind, wouldn’t it make more sense to test the product for ASF virus before it leaves the plant in China?
KE: That’s not possible. Currently, there is no test specifically allowed during manufacturing to determine if there’s ASF contamination. Only government laboratories are authorized to test for ASF and other foreign animal-disease viruses. Furthermore, feed medications are bulk materials, so sampling would represent only a small portion of the total product. That increases the risk of getting false negatives and may give manufacturers a false sense of security.
Q: Some of the API that Zoetis imports from China is used to make CTC and SMZ products in US manufacturing facilities. What precautions are taken with those materials?
KE: We purchase those APIs from Chinese manufacturers that are audited and approved by both Zoetis and the Food and Drug Administration (FDA). The hold time for API we import from China is 78 days after the born-on date, which is consistent with the published guidelines for materials that do not include soy-based ingredients.
Secure shipping
Q: What precautions is Zoetis taking with feed-medication packaging?
KE: Suppliers and transporters of single-use totes and bags used for packaging API or blended products are also dedicated to Zoetis — again to maintain a closed, unidirectional flow of materials. They’re not delivering packaging materials to companies other than Zoetis. All bagged products are stretch-wrapped in polyethylene for added protection and security.
Q: Once a Type A Medicated Article manufactured in China is in a bag or plastic tote, stamped with a born-on date and ready for shipment, how does Zoetis maintain biosecurity between the plants in China and its manufacturing or distribution sites in the US?
KE: That’s the easy part. After products are packaged, they are placed into clean, steel shipping containers, which are then sealed at the plant and shipped by truck to the seaport, where they are loaded onto ships bound for the US. Unless they are opened by a US Customs agent in Seattle or other US port, the containers remain sealed and are shipped by train to Zoetis distribution facilities in Iowa (Des Moines and Eagle Grove).
Q: So typically, how long does it take for the finished products made in China to reach the US distribution points?
KE: Usually, from the plant in China to the Zoetis warehouses in the US, we’re looking at an average transit duration of 80 days or more (which is in accordance with Zoetis’ internal standards). As a result, most Zoetis finished product has already cleared the industry-recommended, 125-day hold time by the time it’s at one of our US facilities. Either way, no finished product with origins in China is shipped to our customers until 135 days after the born-on date.
Q: What about the transit times for API for CTC and SMZ, which is produced in China and shipped to US manufacturing facilities?
KE: It takes approximately 40 days for API made in China to reach our warehouse or manufacturing facilities in the US. After the imported API is delivered to these sites, it is unloaded from the cargo containers and then stored in the original large sacks. They may get blended at the site prior to 78 days, but the finished product will not ship to customers until after 78 days.
Zoetis manufacturing sites
Q: Tell us more about Zoetis’ feed-medication plant in Suzhou, China.
KE: The plant is located about 1 hour northwest of Shanghai. It’s a modern facility — built in 2015, inspected and approved by FDA in 2016 and officially put into production in 2017. It is used only for manufacturing Zoetis feed medications for livestock and poultry. No other products are made there. Products are exported to Europe and the Asia Pacific region, as well as to the US and Canada.
Q: To what extent are feed medications or API made in China regulated by FDA?
KE: Pharmaceutical plants outside of the US that export products to the US are required to comply with the same FDA standards for manufacturing, testing, product handling, safety and packaging that apply to plants in the US. They are also inspected by FDA every 2 years, and those inspections are equivalent to inspections of US or European facilities.
In addition, FDA’s Foreign Verification Program requires importers such as Zoetis to perform certain risk-based activities to verify that food imported into the US — in this case, feed ingredients — has been produced in a manner that meets applicable US safety standards.
Q: The steps Zoetis takes to prevent product contamination are impressive. However, some US customers might ask why these ingredients are produced in China in the first place. One of Zoetis’ top-selling feed medications, BMD® (bacitracin methylene disalicylate), is made in Chicago Heights, Illinois. Why not move manufacturing to a US location for added biosecurity?
KE: That’s easier said than done. Not only from a manufacturing or capacity standpoint, but there are also regulatory considerations. To comply with FDA requirements, we can’t just pick up the CTC or feed-grade lincomycin API, for example, and move it to the US and start blending it with materials produced in the US. All of that — the blending, the mixing, the manufacturing process — would have to go through US government approval, a process that could take years.
It’s also important to remember that products like Lincomix are used worldwide — not just in the US. In fact, products made at Suzhou alone — medicated feed additives plus premixes and soluble powders — are shipped to more than 60 countries in Asia Pacific, Europe and North America. We consider Suzhou to be an ideal location for servicing both the US and other swine markets. For the same reason, it makes sense to source API for our CTC and SMZ products in China.
In summary, we’re proud of our modern manufacturing plant in Suzhou. More important, we are confident in the many biosecurity safeguards and processes we have in place to deliver high-quality, dependable products for the US pork industry.
For Aureomycin, Aureomix S 40/40, ChlorMax 50 and Lincomix:
Caution: Federal law restricts medicated feed containing this veterinary feed directive (VFD) drug to use by or on the order of a licensed veterinarian.
All trademarks are the property of Zoetis Services LLC or a related company or a licensor unless otherwise noted.
This report is produced by the editors of Pig Health Today® on behalf of the US Pork Business of Zoetis.
1 Dee SA, Bauermann FV, Niederwerder MC, Singrey A, Clement T, de Lima M, et al. Survival of viral pathogens in animal feed ingredients under transboundary shipping models. PLoS ONE 2018;13(3): e0194509. https://doi.org/10.1371/journal.pone.0194509
2 Swine Enteric Coronavirus Introduction to the United States: Investigative Report. USDA-Animal and Plant Health Inspection Services, pp. 1-2.
3 Swine Enteric Coronavirus Introduction to the United States: Investigative Report. USDA-Animal and Plant Health Inspection Services, p. 43.4 Dee SA, Bauermann FV, Niederwerder MC, Singrey A, Clement T, de Lima M, et al. Survival of viral pathogens.5 Holding Time Calculation for Feed Ingredients. https://www.swinehealth.org/wp-content/uploads/2018/10/Holding-Time-Calculation-for-Feed-Ingredients.pdf (Accessed Jan. 4, 2019).6 Dee SA, Bauermann FV, Niederwerder MC, Singrey A, Clement T, de Lima M, et al. Survival of viral pathogens.
AUR-00088
Feb 2021
Posted on February 4, 2021
