34 MARCH 2022 • WORLD AQUACULTURE • WWW.WA S .ORG been developed, there are challenges related to unpredictable fecundity, egg quality and occasional deformities during early ontogenetic development. One method to improve hatchery production/quality includes a dietary approach because many nutrients necessary for proper development are maternally transferred to eggs (Lane and Kohler 2006, Migaud et al. 2013, Izquierdo et al. 2015). This motivated us to perform a pilot study in collaboration with a commercial hatchery to evaluate the effect of dietary supplementations of fish oil (high in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)), microalgae oil (high in DHA) and nucleotides on the reproductive performance and subsequent effect on juvenile production and quality. Largemouth bass Micropterus salmoides is a sport fish in the Centrarchidae family, native to North America and widely introduced into Europe, Africa, South America, Japan and China. In the United States, 31 states produce largemouth bass, with sales reaching $27 million in 2018. Freshwater global aquaculture value and production of largemouth bass ranked 16 and 19, respectively, with a total production of 458,000 tons in 2017. Most production occurs in China (99.8 percent of that amount) where it is highly valued as a foodfish (Hussein et al. 2020). In North America, largemouth bass is a highly valued sport fish and also as a foodfish by the Asian community, especially in big cities such as New York, Chicago and Toronto, sparking interest in production. Although reproduction and nursery culture techniques have Challenges in Largemouth Bass Juvenile Production Angel Rojo-Cebreros, Herbert Quintero, Nicholas Romano, David Heikes and Angel Sanchez-Ramirez FIGURE 1. Survival of largemouth bass fry when starved that were spawned from broodstock an unaltered commercial diet (Diet 1) or those top sprayed with fish oil/microalgae oil without (Diet 2) or with nucleotides (Diet 3) over two weeks. FIGURE 2. Individual average length-weight relationship of largemouth bass Micropterus salmoides fry during first four weeks post hatching, from broodstock fish fed three different diets. FIGURE 3. Growth curve of largemouth bass fingerlings during first eight weeks post hatching that were spawned from broodstock fish fed an unaltered commercial diet (Diet 1) or those top sprayed with fish oil/microalgae oil without (Diet 2) or with nucleotides (Diet 3).
RkJQdWJsaXNoZXIy MjExNDY=