BY LINDA McGURK
Indiana Correspondent WEST LAFAYETTE, Ind. — Fish consumption in the beef-loving Hoosier state may be lower than average, but aquaculture is hotter than ever.
And though fish farms have, historically, relied heavily on fishmeal and fish oil for feed, aquaculture scientists at Purdue University are at the forefront of studying plant-based alternatives, mainly soybean meal.
For the state’s fish farmers and soybean growers, this could be a “marriage made in heaven,” said Sonny Ramaswamy, associate dean of agriculture, during a June 28 open house at Purdue’s aquaculture facilities in West Lafayette.
For soybean farmers, the growth of aquaculture spells a new market for soybean meal, and for fish farmers, blending the traditionally used fishmeal with the locally-grown soy alternative could equal substantial savings on feed.
“We, the state’s soybean farmers, see the potential of (Indiana’s) aquaculture industry and its potential as a major consumer of soybean meal,” said Mike Yoder, director of the Indiana Soybean Alliance (ISA). “We want to work with the state’s fish farmers to build a strong aquaculture industry here in Indiana.”
ISA and the United Soybean Board sponsor several of the research projects currently underway at Purdue’s aquaculture lab. Soybean meal has emerged as the most logical alternative to fish-based diets for a number of reasons, according to Anant Bharadwaj, a research associate in the forestry and natural resources department at Purdue.
“Soybean meal has the best balance of amino acids, compared to other plant-based feeds.
“Compared to fish meal, soybean meal is deficient in one or two amino acids, but this can be corrected by adding supplements,” he said. “Soybean meal is economical, nutritious and available – those are the three major factors why we use it.”
Purdue researchers have made great strides in understanding the effects of feeding soybean meal to fish, despite a fire that devastated the aquaculture research facility on Nov. 14, 2004.
Triggered by an unknown electrical malfunction, the raging flames quickly reduced the lab to a smoldering pile of rubble and the next day, charred fish scattered in the debris served as a ghastly reminder of the $1.2 million worth of research projects that had been completely wiped out.
Today a new lab, built on the original site, is bustling with research activity.
“We’re back up and running, and I think we have an even better lab than before,” said Paul Brown, professor of aquaculture and leading fish nutrition researcher at Purdue.
Twelve outdoor ponds and any number of indoor pools and aquariums house a wide range of fish species, including Atlantic salmon, hybrid striped bass, rainbow trout, zebra fish and tilapia. Different species have different diet requirements and some, like catfish, cope better with plant-based protein than others. The researchers are still trying to understand exactly how much soybean meal can be incorporated in different species’ diets.
“Herbivorous fish tolerate more than carnivorous fish,” said Bharadwaj. “In the initial step, we use soybean meal to replace 30-40 percent of the fishmeal, depending on the species. But the ultimate goal is to completely replace fishmeal, and we’re taking small steps to reach it.”
One of the issues researchers have yet to overcome is that plant-based protein appears to slow down growth in the fish. Likewise, some soybean hybrids can have unintended effects on the animals. Bharadwaj said farmers will play an important role in selecting breeds that are suitable for fish farming.
“Once we know what the fish requires, we’ll try to make recommendations to soybean farmers,” he said. “We aim to produce the perfect soybean for fish.”
This farm news was published in the July 11, 2007 issue of Farm World, serving Indiana, Ohio, Illinois, Kentucky, Michigan and Tennessee. |
