The production of catfish accounts for approximately one-third of the total fish production in the United States. Disease management is crucial for sustainable growth and profitability as aquaculture production expands. One of the three major bacterial diseases affecting the U.S. catfish industry is caused by Aeromonas spp., especially the hypervirulent A. hydrophila pathotype that causes significant annual economic losses. Vaccination could be an effective and sustainable alternative to antibiotics in reducing disease outbreaks, and vaccines may be delivered by immersion, injection, or orally. However, immersion and injection-based vaccination can be costly and labor-intensive and are therefore not feasible in large-scale catfish farm production. Oral vaccination has emerged as a cost-effective and non-invasive way to immunize fish. In this study, a synthetic biodegradable polymer - poly (lactic-co-glycolic acid) (PLGA)- was implemented to encapsulate formalin-killed A. hydrophila ML09-119 as an oral vaccine. Encapsulation was accomplished using a double emulsion (W/O/W) solvent evaporation method. The antigen-PLGA emulsion was stabilized with polyvinyl alcohol (PVA), hardened, and freeze-dried particles were ~10 µm in size, suitable for uptake in the gut. Our hypothesis is that channel catfish vaccinated orally with the PLGA-encapsulated antigen will have improved survival rates and enhanced immune responses following an A. hydrophila challenge. Through this work, we will have a more complete understanding of PLGA-based oral vaccination against A. hydrophila infection, which could be a practical strategy for sustainable catfish farming.