An LSU researcher has teamed up with a New Orleans businessman to create an automated process of rearing the microscopic creatures that fish larvae need to eat.

Kelly Rusch, LSU College of Engineering’s associate dean of research and diversity, said the system, if successfully commercialized, could help prevent overfishing of many species and make domestic aquaculture a more viable alternative to buying seafood from foreign fish farms.

Rusch has a provisional patent for her automated continuous rotifer culture system, which generates a constant supply of rotifers, the microscopic zooplankton that fish larvae eat during a crucial stage of development. The system has been licensed to Aquaculture Systems Technologies LLC in New Orleans, headed by Douglas Drennen, a former colleague of Rusch’s at LSU. It is now in the commercial and marketing phase of development.

The key to Rusch’s system is that it uses process control technology to monitor the rotifers and their environment — its population, temperature, food supply — and doses the tanks appropriately.

The system requires virtually no human supervision, which cuts down on the labor costs that eat into aquaculture’s slim profit margins, which Rusch and Drennen says will be the key to the system’s success.

“For the U.S. to compete globally, it has to expand its aquaculture industry,” Rusch said.

Many popular fish are overharvested or at their limit, Rusch said. She pointed out that when blackened redfish became popular in the 1990s, fishing for the species had to be banned for a while.

Rusch said the United States imports the vast majority of its seafood — 80 percent, according to LSU — with the $9 billion seafood trade deficit second only to the petroleum deficit.

Fish farms now can cultivate this food source manually — and absorb the costs associated with it — or buy the finished product from the West Coast, which is also expensive.

“The problem with that approach is it costs a lot of money,” Rusch said

This, she said, is what makes it more economical to just buy farm-raised seafood from foreign countries, primarily southeast Asia, where labor and electricity costs are lower, along with environmental standards.

Rusch came to LSU in 1987, working in the area of microorganisms, microalgae and zooplankton.

In 1993, she and LSU’s Dr. Ron Malone developed an automated system to cultivate algae called HISTAR, or Hydraulically Integrated Serial Turbidostat Algal Reactor.

Malone had formed the company that would become Aquaculture Systems Technologies to develop a water filtration system he had come up with that used beads to clean water. The company began the process of commercializing HISTAR, hiring Drennen, who worked at LSU with Malone and Rusch as a research associate.

Drennen soon bought the company and has been working to commercialize HISTAR with the help of federal innovation grants from the National Science Foundation. He said those systems, which could be useful for both aquaculture and biofuels applications, could begin to be sold next year.

During this time, Rusch began working extensively with rotifers and began looking at continuous, automated processes that could cultivate rotifers, work that she said in the ensuing years was halting.

By the early- to mid-2000s, she began work on a prototype system that could create the smallest of the three types of rotifers, a creature only 75 microns, or three-quarters the diameter of a human hair.

The rotifers are first inoculated and grown in a culture tank. They are then moved to a “grow out” tank where the system takes PH readings and doses the tank with algae, which is food for the rotifers, based on the population level in the tank. The system harvests rotifers out of that tank and puts them in a holding tank. There, the system monitors and adjusts the oxygen level and temperature and disburses the rotifers to the fish.

Rusch said the system is in the second phase of a Small Business Innovation Research grant from the National Science Foundation. She received a provisional patent last year and expects to file for a full patent by the end of the year.

Rusch said refining the photosensor that estimates the population is key to getting the full patent. Some of the filtration system is quite new as well, Rusch said, because of the small size of the rotifers.

Rusch said there is more than one way the system could work in a commercial setting. A hatchery could buy a system and have it installed to produce the rotifiers to raise seafood, or a company could use the system to produce and supply rotifers. The tank size, she said, is scalable.

Aquaculture Systems Technologies has 12 employees and is on track to reach sales of $2 million around the world this year, primarily on its bead filtration system, Drennen said. He is currently working on revising the software system on HISTAR and could begin selling them next year.

Drennen said he expects the market to develop slowly, with maybe five sold in the first year and then 10 or 15 in the second.

“As there’s more and more interest in culturing more fish through aquaculture, this technology is going to be more and more important,” he said.

As for the rotifer system, the work now focuses on further developing the turbidity sensors that tell how many rotifers are in the tank. LSU is not alone in trying to find ways to commercialize the technology that comes from its colleges and faculty.

“I think one of the keys to commercializing technology that comes out of universities is you have to have a good working relationship with the commercial partner,” Rusch said. “It takes communication and trust. Everyone is in it for the same cause.”

Rusch said it may also be much simpler to do it with a small business, because small businesses tend to be more flexible and have cultures similar to university labs — more so than a large corporation that is locked into its own way of doing things.

She said who owns what intellectual property needs to be worked on the front end of the deal. In her case, Rusch is the one with her name on the patent, and the technology is licensed to Aquaculture Systems.

“I’ve seen university/industrial partnerships that work very, very well and I’ve seen ... ones that have fallen apart,” she said. “The key is the partners have to have a communication pathway throughout the entire process. It’s not, ‘You go do your thing and I’ll do mine.’ You have to have that trust base there.”