Browsing by Author "Gonçalves, Fernando H."

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    Assessing Economic Contributions of the Virginia Seafood Industry: An Estimation Framework Utilizing Primary Data
    Gonçalves, Fernando H.; van Senten, Jonathan; Schwarz, Michael H.; Hegde, Shraddha (MDPI, 2024-05-26)
    With a focus on seafood industries, this study provides a framework for economic contribution assessments, outlines Virginia’s seafood supply chain components, and evaluates the direct, indirect, and induced economic impacts of Virginia’s seafood industry in 2019. Utilizing an analysis-by-parts method in IMPLAN, primary expenditure data from watermen, aquaculture farmers, processors, and distributors were collected through surveys. The efficacy of obtaining primary data through stakeholder surveys heavily relies on the investigator’s interpersonal skills to establish trust and elucidate the study’s benefits, particularly its potential to inform policy decisions. In 2019, the Virginia seafood industry’s estimated total economic contributions amounted to USD 1.1 billion, supporting 7187 individuals. This impact encompasses 6050 direct jobs, 523 indirect jobs, and 614 induced jobs, primarily benefiting watermen and coastal communities. Furthermore, the industry’s influence extends beyond its immediate economic sphere, supporting diverse sectors such as polystyrene foam manufacturing, boat building, sporting and athletic goods, and commercial and industrial machinery. Wages and salaries disbursed throughout the seafood supply chain ripple to Virginia’s economy, benefiting nondepository credit intermediation, owner-occupied dwellings, and real estate sectors. Future research focusing on seafood sales in restaurants and retail outlets will complete the understanding of the seafood industry’s broader economic impact on the state.
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    Assessment of Water Quality, Growth of Penaeus vannamei, and Partial Budget in Super-Intensive BFT and RAS: A Comparison Between Sustainable Aquaculture Systems
    Ramiro, Bianca de Oliveira; Wasielesky, Wilson; Pimentel, Otávio Augusto Lacerda Ferreira; Sun, Taozhu; McAlhaney, Ethan; Urick, Stephen; Gonçalves, Fernando H.; van Senten, Jonathan; Schwarz, Michael H.; Krummenauer, Dariano (MDPI, 2024-12-15)
    This study evaluated water quality, growth, and partial budget analysis (PBA) for Penaeus vannamei, comparing super-intensive Biofloc Technology (BFT) and Recirculating Aquaculture Systems (RAS). The 69-day trial used 100 L units with two treatments (RAS and BFT), each with three replicates. Shrimp were initially reared in a 30-day nursery to a weight of 0.10 ± 0.04 g and then stocked at 500 shrimp m−3. Biofloc growth in BFT was promoted by maintaining a C:N ratio of 15:1, adding dextrose when total ammonia nitrogen (TAN) reached 1 mg L−1. Probiotics (3 g m−3) were administered daily to both groups. TAN levels in BFT initially spiked but stabilized after 36 days. Vibrio abundance was initially higher in RAS, but by the end of the trial, it was higher in BFT. Final weight, weekly growth ratio, and yield were greater in BFT, whereas feed conversion ratio (FCR) and water use were higher in RAS. Survival rates were 83.33% in BFT and 88% in RAS. BFT achieved a superior net benefit/cost compared to RAS. Although RAS more effectively controlled nitrogenous compounds, BFT exhibited better growth performance, with higher final weights, lower FCR, and better Vibrio management. The partial budget analysis indicated an economic advantage for BFT, with a net positive benefit of $2270.09 when shifting from RAS to BFT due to lower operating costs and higher shrimp yield. Among these two sustainable production systems, BFT was more productive while utilizing less natural resources.