Aquaculture is a growing sector of agriculture worldwide, with nearly 1 billion people depending on fish as their primary protein source. Even though concerns over sustainability, overfishing and cost of production have complicated the development of more commercial aquaculture operations, the industry continues to look forward.
To help meet the growing demand for fish worldwide, in March 2015 the U.S. Grains Council (USGC) began two independent aquaculture feeding trials using distiller’s dried grains with solubles (DDGS) in Vietnam.
Historically, Peruvian fishmeal is the typical protein source in Vietnamese aquaculture. Because of recent product shortages and increasing prices, fish farmers are seeking a replacement. The combination of DDGS and soybean meal is currently being researched. In the two USGC studies, DDGS is being fed at 5, 10 and 15 percent inclusions in the diets, as well as a control.
Kevin Roepke, USGC regional director for South and Southeast Asia, said all diets with DDGS are more cost effective than the control diet.
“The goal of this project is to show the industry you can feasibly utilize plant-based proteins, both DDGS and soybean meal, as combined sources of protein in fish diets,� Roepke said. “The two ingredients complement each other very well and can at least partially replace expensive fishmeal.�
The studies are using Pangasius, a medium- to large-sized shark catfish native to South and Southeast Asia. A mild white-flesh fish, Pangasius is popular in the Asian and U.S. markets.
Another aspect of the study will assess any changes in flesh color, addressing concerns that the xanthophyll, a yellow or brown plant pigment, in DDGS may cause a yellow color. The fish in this trial will be harvested, hopefully in September 2015, and analysis of the filet colors will determine what impact xanthophyll has on the finished, frozen product.
Additionally, Roepke hopes the study will be a starting point for introducing corn to Vietnamese fish feeders as an energy source. If the initial trials with DDGS are positive, corn could be used in their rations in the future.
“These studies are being done on a commercial scale, simulating real world conditions,� Roepke said. “Once fish producers realize DDGS can save them money in their formulations without sacrificing quality, increasing the inclusion rates of DDGS and corn will quickly follow.�