Imported feed ingredients: sourcing, biosecurity, shipping hold vital to product integrity and safety

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 U.S. pork production?

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 the pork industry and government officials to minimize the risk. It’s important to note that while three variants of coronavirus (PEDV, PEDV InDel and PDCoV) and Senecavirus A have entered the U.S. since 2013, we can’t say with certainty that imported feedstuffs acted as fomites for these pathogens but the possibility does exist.²

Where do the risks for virus contamination lie?

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.

What imported feedstuffs have the most potential for transmitting ASF?

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.¹

Zoetis is a leading supplier of medicated feed additives for the U.S. pork industry. Are any of Zoetis’ swine feed medications made in China?

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 (chloretetracycline), ChlorMax® 50 (chlortetracycline), Lincomix® 20 and Lincomix® 50 (lincomycin). Our Lincomix products, which contain lincomycin, are made entirely at our plant in Suzhou, China, and then exported to the U.S. and other markets. The API, or active pharmaceutical ingredients, for sulfamethazine (SMZ) and some chlortetracycline (CTC) products used in the U.S. are also produced in China and obtained from sources that meet Zoetis’ rigid manufacturing standards.

To what extent are feed medications or API made in China regulated by FDA?

Pharmaceutical plants outside of the U.S. that export products to the U.S. are required to comply with the same FDA standards for manufacturing, testing, product handling, safety and packaging that apply to plants in the U.S. The licensed facilities are inspected by FDA every 2 years, and those inspections are equivalent to inspections of U.S. or European facilities.

Current Good Manufacturing Practices (cGMPs) are included in the FDA standards and encompass the conditions in which the product is produced, not the product itself. The word “current” means present or today, not the past or future and requires the adherence to a current general standard of manufacturing to ensure product specifications and labeling are met. Compliance with cGMPs ensures good housekeeping, inventory controls, precise documentation of production processes, ability to trace and locate product in the field and back through production if necessary. Furthermore, the compliance with cGMP ensures the integrity of the product and integrity of the product and all other products within the facility are maintained.

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 U.S. — in this case, feed ingredients — has been produced in a manner that meets all risk-based measures.

Are any of the inert or excipient ingredients in Zoetis feed medications from China potential carriers of the ASF virus?

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 U.S.-sourced and are considered minor risks for virus transmission. Our Lincomix products are made with soybean hulls, the outer skin of the soybean, produced in the Americas and processed in China. Soybean hulls are considered moderate risks for virus transmission, however, the cGMP processes provide assurance the proper use and handling of such materials are in place to safeguard products from contamination.

Will the use of soybean hulls processed in China for Lincomix impact risk of contamination?

Lincomix is made from soybean hulls from conventional soybeans sourced in the U.S. and Brazil and then transported to China for processing. The soybean hulls are 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. In addition, all drivers are dedicated to Zoetis shipments and not contracted through other manufacturers. The people and equipment handling the soybean hulls maintain a unidirectional flow – stipulating they flow in only one direction with elevated biosecurity along the way. Due to the high level of biosecurity that Zoetis has in place for processing and transportation of these soybean hulls, there is little risk of virus contamination.

Tell us more about Zoetis’ feed medication manufacturing plant in Suzhou, China.

The plant is located about one hour northwest of Shanghai. It was built in 2015, inspected and approved by FDA in 2016 and officially put into production in 2017. The plant is used only for manufacturing Zoetis feed medications for livestock. No other products are manufactured there. The products manufactured at Suzhou are exported to Europe, Asia Pacific region, U.S. and Canada.

Are the soybean hulls quarantined before they enter the Lincomix plant?

Soybean hulls are shipped directly from the processing plant to the miller, and then to Suzhou, China plant. The soybean hulls are then stored in dedicated, sealed silos and used shortly after delivery.

After processing and formulation into saleable product, how long does Zoetis hold the medicated feed additives prior to shipment and distribution to their customers?

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 U.S. pork industry, including the NPB, NPPC, AASV, and SHIC, Zoetis then implemented procedures to increase product hold time to 135 days, 10 days more than the minimum, after the born-on date or when the product is bagged and sealed.

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? 

Currently, testing for ASF contamination is not allowed during manufacturing. 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. This would also increase the risk of getting false negatives and may give manufacturers a false sense of security.

What precautions is Zoetis taking with feed-medication packaging?

Suppliers and transporters of single-use totes and bags used for packaging API or blended products are 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.

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 U.S.?

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 U.S. Unless they are opened by a U.S. Customs agent in Seattle or other U.S. port, the containers remain sealed and are shipped by train to Zoetis distribution facilities in Iowa (Des Moines and Eagle Grove).

Typically, how long does it take for the Lincomix products produced in China to reach the U.S. distribution points?

Usually, from Suzhou, China to the Zoetis warehouses in the U.S., is 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 U.S. facilities. Either way, no finished product with origins in China is shipped to our customers until 135 days after the born-on date.

The steps Zoetis takes to prevent product contamination are robust. However, some U.S. customers might ask why these ingredients are produced in China in the first place. Why not move manufacturing to a U.S. location for added biosecurity?

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, acquiring regulatory approval for relocating the CTC or feed-grad lincomycin API to the U.S., and subsequently blending them with domestically produced materials, is a time-consuming process. Every step, including blending, mixing, and the entire manufacturing process, must undergo U.S. government approval — a procedure that could extend over several years.

In summary, we’re proud of our manufacturing plant in Suzhou, China. More important, we are confident in the many biosecurity safeguards and cGMP processes we have in place to deliver high-quality, dependable products for the U.S. 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.