The Production of Fast-Growing, Sterile Walleye Hybrids through Genetic and Endocrine Technologies
Jeffrey Malison
The walleye is one of the most highly valued food and sport fish in the Great Lakes region. Because of its high market value and limited supply, this species is an excellent candidate for commercial aquaculture. However, the commercial production of food-size walleye is constrained by the fish’s slow growth when reared under intensive culture conditions.
This project is investigating the potential of three technologies to be used in combination to produce walleye strains with significantly improved growth. Hybrids, monosex female populations, and genetic triploids (i.e., individuals with three sets of chromosomes) of other species have shown advantages in growth and survival rates, total size, docility, and adaptability.
Researchers are developing methods for producing monosex female hybrid walleye; they are developing and testing methods for inducing in them triploidy at high rates; and they are comparing the growth, feed conversion, and reproductive development of these hybrids to diploid hybrid and purebred walleye.
The resulting techniques will produce fish strains with significantly improved growth, thereby spurring the development of a commercial food-size walleye aquaculture industry. These technologies will also be useful tools for enhancing recreational fisheries in and around the Great Lakes.
Update - February 1999
Hydrostatic pressure shock methods to induce triploidy in a high percentage of hybrid walleye were successfully developed in the spring of 1998. Triploid and diploid hybrids and diploid purebred walleyes have been produced, and studies comparing the growth, performance, and reproductive development of these fish are under way. Two year-classes of a lake strain of female walleyes and one year-class of a river strain of saugers are being reared and should reach reproductive maturity in the spring of 1999. The saugers were treated at the juvenile stage with 17
a-methyltestosterone to induce partial sex inversion in the females, and present plans are to produce monosex female hybrid walleye next spring.
For a free program guide that describes
each of the projects currently funded
by the UW Sea Grant Institute, please contact:
Linda Campbell
Communications Office
Sea Grant Institute
University of Wisconsin-Madison
Goodnight Hall, 1975 Willow Drive
Madison, WI 53706-1103
USA
Phone (608) 263-3259
Fax (608) 262-0591
