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Inactivation by hydrogen peroxide and pH manipulation are two novel methods used recently in experimental vaccines against Streptococcus agalactiae in Nile tilapia. Here we describe in detail inactivation using novel methods as well as the classical method of inactivation. These vaccines showed similar moderate efficacy when compared to the conventional formaldehyde vaccine. In addition, we describe the inclusion of adjuvants in a hydrogen peroxide vaccine.

Inactivation by hydrogen peroxide and pH manipulation are two novel methods used recently in experimental vaccines against Streptococcus agalactiae in Nile tilapia. Here we describe in detail inactivation using novel methods as well as the classical method of inactivation. These vaccines showed similar moderate efficacy when compared to the conventional formaldehyde vaccine. In addition, we describe the inclusion of adjuvants in a hydrogen peroxide vaccine.

Made available in DSpace on 2020-12-10T20:09:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-11 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The increasing use of agrochemicals negatively affects the environment while the generated residues impact the hydrographic networks which feed the rivers and fishing ponds, so this work investigates pesticide contamination in the supply and fishing tank waters and bottom sediment of fee-fishing ponds located in micro-basins planted with sugarcane. The results are expected to indicate the water contamination level and the impact on both the environment and human health. Therefore, water and bottom sediments from fishing ponds nearby sugarcane plantations were sampled quarterly over a year. The pesticide residues in the samples were determined by high-performance liquid chromatography coupled to mass spectrometry. The contaminants detected in the ponds were tebuthiuron (2.908 ng mL(-1)), metolachlor (1.211 ng mL(-1)), hexazinone (1.065 ng mL(-1)), atrazine (1.008 ng mL(-1)), ametryn (1.004 ng mL(-1)), and clomazone (0.858 ng mL(-1)) in the water samples while metolachlor (2.308 ng g(-1)), tebuthiuron (0.540 ng g(-1)), hexazinone (0.394 ng g(-1)), and isoxaflutole (0.004 ng g(-1)) were detected in the sediment samples. Additionally, the results show that the size of sugarcane cultivated area nearby the fishing ponds, herbicide physicochemical parameters, and applications coinciding with high rainfall are all relevant factors for water contamination. Furthermore, sediment contamination is directly correlated with the herbicides in the water ponds. Univ Estadual Paulista Julio de Mesquita Filho UN, Ctr Aquicultura CAUNESP, Via Acesso Prof Paulo Donato Castellane S-N, BR-14884900 Jaboticabal, SP, Brazil Univ Estadual Paulista, Nucleo Pesquisa Avancada Matol NUPAM, Ave Univ 3789, BR-18610034 Botucatu, SP, Brazil Univ Estadual Paulista Julio de Mesquita Filho UN, Ctr Aquicultura CAUNESP, Via Acesso Prof Paulo Donato Castellane S-N, BR-14884900 Jaboticabal, SP, Brazil Univ Estadual Paulista, Nucleo Pesquisa Avancada Matol NUPAM, Ave Univ 3789, BR-18610034 Botucatu, SP, Brazil

Made available in DSpace on 2020-12-12T02:17:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-10-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Streptococcus agalactiae is considered the main bacterial pathogen in cultured Nile tilapia. Formaldehyde-inactivated vaccines are the most accepted method for prevention and control of the disease. However, alternative inactivation methods for S. agalactiae vaccines have not been fully explored. Recently, we developed a hydrogen peroxide-inactivated vaccine against S. agalactiae with moderate efficacy, with the possibility to improve vaccine efficacy by adding adjuvants. The current study compared the efficacy of aluminum hydroxide and Freund's incomplete adjuvant (FIA) incorporated into a novel hydrogen peroxide-inactivated intraperitoneal vaccine against S. agalactiae for Nile tilapia fingerlings. The relative percentage survival (RPS) for aluminum hydroxide-adjuvanted vaccine (59.3%), and FIA-adjuvanted vaccine (77.8%) were higher than the vaccine without adjuvant (40.7%). In addition, fish immunized with aluminum hydroxide-adjuvanted vaccine had significantly higher levels of specific antibodies than control fish at 4 weeks post vaccination (wpv). Blood lymphocytes counts showed a decrease in vaccinated groups when compared to control fish, suggesting white cells migration to the tissues where antigen presentation is ongoing. Fish that received FIA-adjuvanted vaccine exhibited persistence of adjuvant deposits on intraperitoneal surfaces for at least 4 wpv that may be related to its superior performance compared to aluminum hydroxide adjuvanted vaccine, which did not evidence any type of deposit at any sampling times. The results observed in this study demonstrate that hydrogen peroxide-inactivated vaccine administered with either aluminum hydroxide or FIA induce optimal levels of protection, with a superior performance for FIA vaccine, which could be a good alternative to conventional formaldehyde-inactivated vaccines against S. agalactiae, due to its shorter manufacture time, and less toxicity. Aquaculture Center of Unesp (Caunesp) Sao Paulo State University (Unesp), Via Prof. Paulo Donato Castellane, km 05 Aquatic Pathobiology Laboratory Sea Institute of Peru (IMARPE), Esquina Gamarra y GeneralValle s/n, Chucuito Department of Veterinary Pathology School of Agricultural and Veterinary Sciences (FCAV) Unesp, Via Prof. Paulo Donato Castellane, km 05 Aquaculture Center of Unesp (Caunesp) Sao Paulo State University (Unesp), Via Prof. Paulo Donato Castellane, km 05 Department of Veterinary Pathology School of Agricultural and Veterinary Sciences (FCAV) Unesp, Via Prof. Paulo Donato Castellane, km 05 CNPq: 141835/2018-4 FAPESP: 2018/06137-1 FAPESP: 2019/02339-1