Immune responses induced by inactivated vaccine against Aeromonas hydrophila in pacu, Piaractus mesopotamicus

Autor(es)

Vaz Farias, Thais Heloisa ^[1] ; Arijo, Salvador ^[2] ; Medina, Alberto ^[2] ; Pala, Gabriela ^[3] ; da Rosa Prado, Ed Jhonny ^[3] ; Montassier, Helio Jose ^[4] ; Pilarski, Fabiana ^[1] ; de Andrade Belo, Marco Antonio ^{[3, 5]}

Afiliação do(s) autor(es)

^[1] Aquaculture Ctr UNESP CAUNESP, Lab Aquat Organisms Pathol Lapoa, Rodovia Acesso Paulo Donato Castellane S-N, Jaboticabal 14884900, SP - Brazil

^[2] Univ Malaga, Fac Sci, Dept Microbiol, Malaga 29071 - Spain

^[3] Sao Paulo State Univ, Dept Prevent Vet Med, UNESP, Rodovia Acesso Paulo Donato Castellane S-N, Jaboticabal 14884012, SP - Brazil

^[4] Sao Paulo State Univ, Dept Microbiol, UNESP, Rodovia Acesso Paulo Donato Castellane S-N, Jaboticabal 14884012, SP - Brazil

^[5] Brazil Univ, Lab Anim Pharmacol & Toxicol, Av Hilario da Silva Passos 950, Descalvado 13690000, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: FISH & SHELLFISH IMMUNOLOGY; v. 101, p. 186-191, JUN 2020.
• Citações Web of Science: 1

Resumo

Aeromonas hydrophila is responsible for outbreaks of a severe infectious disease in fish farms around the world and is one of the major causes of economic losses to the neotropical fish farmers. This study assessed the induction of immune responses and protection against A. hydrophila in pacu, Piaractus mesopotamicus, vaccinated through intraperitoneal and immersion route with inactivated virulent strain. Fish were randomly distributed in three vaccinated groups: intraperitoneal (i.p.) route; immersion; and immersion + booster; and control group (unvaccinated). All vaccination protocols used the concentration of 1.7 x 10(8) CFU mL(-1) of inactivated A. hydrophila., and an oil adjuvant was used for vaccine prepararion for i.p. route vaccination. Blood and skin mucus from 9 fishes per treatment were collected at 14, 28, 42 and 84 days post-vaccination (DPV) for determination of lysozyme concentration in skin mucus, as well as antibodies anti-A. hydrophila in blood serum and skin mucus. Fish were challenged at 84 DPV with homologous and virulent strain of A. hydrophila for evaluation of resistance against bacterial infection. The results demonstrated that vaccination with inactivated A. hydrophila suspension by i.p. or immersion resulted in significant increase of skin mucus lysozyme and specific antibody levels in serum and skin mucus, at 28 and 42 DPV, and this increase in innate and adaptive immunity remained significant in pacu vaccinated through i.p. route up to 84 DPV. Although no significant differences were observed in the survival study, pacu vaccinated through i.p. route presented 31,33% of relative percentage survival (RPS) in LD50-96h when compared unvaccinated fish challenged at 84 DPV. The results observed in this study indicate that vaccination programs with inactivated A. hydrophila, including booster doses by i.p. or immersion routes, could result in more effective protection in pacu against this bacteriosis, by increasing innate and adaptive mucosal and systemic immune responses. (AU)

• Processo FAPESP: 12/12256-7 - Estudo da participação da insulina e do efeito glicocorticóide exógeno sobre a resposta inflamatória aguda de tilápias do Nilo, Oreochromis niloticus, desafiadas com Aeromonas hydrophila.
• Beneficiário: Marco Antonio de Andrade Belo
• Modalidade de apoio: Auxílio à Pesquisa - Regular