Intervet calls 50 countries -- and Worthington -- home: Mergers continue to promote expansion of product lines

WORTHINGTON -- Intervet Schering-Plough has a presence in 50 countries around the world, but boasts its smallest manufacturing site along Lake Street on Worthington's south side.

Williams and Heeren
Pat Williams (left), site general manager, and Luann Heeren, purchasing and planning supervisor, stand in the lobby of the administration building of Intervet Schering-Plough in Worthington. (JULIE BUNTJER/DAILY GLOBE)

WORTHINGTON -- Intervet Schering-Plough has a presence in 50 countries around the world, but boasts its smallest manufacturing site along Lake Street on Worthington's south side.

Beyond its gate, company employees work to produce vaccines used to treat everything from cattle and swine respiratory diseases to equine influenza and ailments in poultry.

The company's roots in Worthington go back several decades, when it was originally established as Oxford Laboratories. Luann Heeren, purchasing and planning supervisor, has been with the company for 30 years.

Since then, there have been a series of nine buyouts and mergers, and the company is actually owned now by Merck. Another potential merger is under way, however, with Merial of Duluth, Ga., buying out the operations.

Pat Williams has served as site general manager of the Worthington facility for the past six years, although he got his start with the company 18 years ago in Millsboro, Del.


"Every merger brought in a new product line," Williams said. "The Intervet Schering-Plough merger just made Intervet much, much stronger -- in the companion animal arena and in just about every product class."

The Worthington facility is the only Intervet Schering-Plough operation in Minnesota and is spread out on a campus made up of seven buildings. The site includes administration, production, warehousing, maintenance, quality control and a research site near Rushmore. Altogether, the company has 69 employees here, while globally there are approximately 94,000 employees in the Merck family. Roughly 8,200 of them work in the animal health industry branch. Williams said the company has 29 manufacturing facilities worldwide, including five in the United States that cater to animal health.

"We run the gamut of producing bacterial and viral antigens for swine, cattle, equine, poultry and companion animals -- cats and dogs," said Heeren of the Worthington facility.

The vaccine products manufactured at the site consist of live and killed bulk antigens, with some live antigens freeze-dried into cakes. The products produced at this site are shipped to other Intervet Schering-Plough sites in Millsboro, Del., Elkhorn, Neb., and DeSoto, Kan., for further manufacturing and packaging. Product from the Worthington site is also exported to the Netherlands, Spain and the United Kingdom.

"We used to ship a lot of antigens internationally from here, but we don't do as much anymore," Williams said. "Now, we send them to our distribution site in Omaha (Neb.), and they take care of shipment for domestic and international (orders)."

Product lines

The top producing product line at Worthington's Intervet location is Vista Once SQ, a respiratory vaccine for cattle. After being off the market for a while, Vista was reintroduced in January and "will probably take its place back as the leading respiratory vaccine for cattle," Williams said. The product contains a combination of five viruses and two bacteria, which makes it unique, he added.

In 2008, Vista had 60 percent of the market share, according to Heeren. She said there will be an estimated production of approximately 6 million individual doses at the Worthington facility this year.


"Right now, it's being distributed only in the U.S., but we're hoping to expand into Canada and maybe South America," Williams said.

Worthington is the exclusive manufacturer of not just the Vista line, but four other products as well.

Mycovac L is the secondlargest product line of those manufactured locally. This vaccine is used to treat the effects of mycoplasma gallisepticum in chickens. The live mycoplasma product has been on the market for 18 years and is distributed across the U.S., in the European Union and the rest of the world, Williams said.

"It's one of the best-performing vaccines on the market," he added.

Nine of the 12 antigens for the Prestige and Encevac product lines are manufactured in Worthington and are used in different combinations for multiple products used to treat equine diseases caused by equine herpes virus, equine influenza virus and encephalomyelitis. The antigens are then shipped to the facility in DeSoto, where they are formulated into the final product.

The site produces multiple antigens for the Prosystem and Magestic product lines, which are used in the prevention of rotaviral diarrhea, TGE, rhinitis, pneumonia and parvo virus in swine. The Argus SC/ST product is used in the prevention of pneumonia, diarrhea and septicemia caused by salmonella choleraesuis in swine. The products made from multiple combinations of antigens manufactured in Worthington are used across the U.S. and the rest of the world, Williams said. As for the Argus line, it's well established in the market and is used to treat salmonella.

In a day's work

Intervet Schering-Plough's Worthington facility is divided into four main departments in its manufacturing area: media prep, bacterin (fermentation), virus (cell culture) and filling/freezedrying. The media prep group prepares broths/media that are used in the propagation of either the bacterial or viral organisms. The organisms are propagated in the virus and bacterin departments and are processed live or inactivated. Inactivated antigens are used in the attenuated vaccines. Some live cultures are lyophilized by the filling/freeze-drying department, and it is this drying process that aids in the preservation and stability of the live cultures. Basically, the product starts out as a liquid, and then is freezedried into a cake form.


Product is shipped out from the local facility every other week.

Heeren said the company produces a forecast each year to identify what products the Worthington facility will manufacture, but that is tweaked on a monthly basis.

"If there's a run on the market, you get that product back on the market as soon as possible," Williams said. "Marketing plays a huge role in what we manufacture here."

"One week you may be doing five different antigens on the bacterial side," Heeren said about the work. Then, in the freeze-drying area, there could be four different products being made in one week.

The local facility operates with two manufacturing shifts in both fermentation and media prep, and employees cover shifts to keep it open seven days per week.

"Every technical employee is trained in every facet of the activity in their department," Williams said.

Growth potential

Williams said Intervet Schering-Plough's Worthington facility is adequate for today, but he would like to see the company grow locally.

"We've done a lot of things in this small area -- in our manufacturing and other buildings," he said. "We want to grow the business as much as we can."

Williams would like to see the local facility do more manufacturing of products for use in companion animals.

"It gives us more flexibility," he said. "We produce basically for larger animals and poultry. We would like to get into more of the singledose type of product."

Sample Inspection
An Intervet employee inspects a sample in a lab inside the Worthington facility. (SUBMITTED PHOTO)

Julie Buntjer became editor of The Globe in July 2021, after working as a beat reporter at the Worthington newspaper since December 2003. She has a bachelor's degree in agriculture journalism from South Dakota State University.
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