Hybrid catfish are one of the greatest opportunities for Southern aquaculture in USA, but before this market can grow up faster there are some challenges that researchers have to face.
Many farmers want to raise hybrids because they’re hardier, have improved growth rates and improved feed conversion. One of the main problems is that the hybrid has a smaller head in relation to its body size, and so they tend to “gill” themselves when being sorted.
David Heikes, Arkansas Extension catfish specialist, seems to have find a solution. “Over the years, I’ve worked on different grading systems. The floating in-pond grader was essentially a bar-grader with horizontal bars just below the grading surface. It was used on hybrids, but the problem is there are so many fish at harvest to process through that machine. [...] Essentially, I’ve come up with a 4-foot-tall, 20-foot-long, flexible grid with a set aperture. The aperture is set according to what fish we’re going after. For example, if we want fish to go to a regular processing plant, we’ll choose a spacing around 1.9 inches. For a gut-market plant, we’ll choose a much wider spacing.”
And this patent could also be applied to others kind of fish. Most other farm-raised species must be graded by hand with box graders or some sort of mechanized grading machine. For more information about this project you can check here.
