Genetics and Genomics:
Aquaculture researchers at the OCARD have been developing microsatellite markers and single nucleotide polymorphic (SNP) markers for applications in the Midwest aquaculture species, especially yellow perch. Currently, we are developing more SNP markers using next generation sequencing technology for whole genome QTL mapping for yellow perch. We are analyzing genetic diversity of different strains and genetically improved lines of yellow perch and largemouth bass using both SNPs and microsatellites. We are also conducting functional genomics research to identify genes associated with traits of interest such as growth, stress, spawning time, ω-3 fatty acids synthesis and compensatory growth for yellow perch. We have completed two projects on genotype by environment interaction in yellow perch. We have also been conducting studies to identify the sex determination mechanism of bluegill.
Multiple improved lines of yellow perch have been developed, and over one million genetically improved fish have been distributed to fish farms. Two-year on-farm tests on three sites in two states show that our improved fish exhibited 42% higher production, and 32% higher growth rates even while having 27.8% higher survival than local strains. We have selected yellow perch that better utilize soybean-based diets. We are developing all-female populations of yellow perch through selective breeding. A phenotypically male population with female genotype has been created in yellow perch, which could produce fast-growing all-female populations for the aquaculture industry. Through selective breeding, we have created an all-male population of bluegill which would grow 40-50% faster than a mixed-gender population. In addition, a project on the evaluation of hatchery stocks and wild populations of largemouth bass across North America and Asia has been completed. The results of this study provide a valuable base for developing a future selective breeding program for largemouth bass.
Nutrition and Feed:
We are developing alternative protein sources for aquaculture diets. We have evaluated modified soybean protein concentrate as a fish meal replacer in the yellow perch diet, and found soy protein concentrate could replace 50% of the fish meal protein in the yellow perch diet without compromising the growth and health of the fish, and also exhibited better growth performance than soy bean meal fed groups. In addition, we are also developing new biomarkers by using genomics (gene expression analysis), proteomics (protein expression analysis) and metabolomics (metabolite profiling) approaches to define a healthy phenotypic fish.
Stress and Disease:
We are investigating stress response to various husbandry and environmental stressors such handling and temperature in farmed fish, the relationship between stress and fish disease, gene expression patterns associated with various stressors, fish immune-relevant genes and their relation to stress, and probiotics, natural products, and bioactive substances and their effect to counteract and minimize the stress in fish. The major goal of our research is to reduce and minimize stress, uphold a healthy aquatic environment, decrease disease incidence, inhibit the spread of diseases and mortality related to handling and low and high temperature for yellow perch and bluegill.