Antioxidant Role of Selenium in Rats with Experimental Acute Otitis Media

The aim of this prospective experimental animal study was to determine whether selenium had a protective effect on oxidative stress in rats with acute otitis media, by measuring the alterations of antioxidant parameters and lipid peroxidation on days 4 and 10 after inoculation into the middle ear. Streptococcus pneumoniae was inoculated into the middle ear cavities of 32 rats in animal laboratory of a tertiary medical center. Group 1 served as the control group and the animals were administered 1.5 ml/day saline. Group 2 received 0.2 mg/kg/day oral selenium for 10 days. The blood samples of each group were obtained on post-inoculation days 4 and 10. The levels of thiobarbituric acid reactive substances, albumin, total sulphydryl, superoxide dismutase and glutathione peroxidase were investigated. Day 10 level of thiobarbituric acid reactive substance in group 2 was lower than the day 4 level of the same substance in the control group. Although glutathione peroxidase and superoxide dismutase levels significantly decreased starting from 4th day until 10th day in group 1, their levels increased in group 2. Day 10 levels of albumin and total sulphydryl in group 1 were significantly higher than day 4 levels in group 2. We found that selenium supplementation for 10 days decreased thiobarbituric acid reactive substances and increased glutathione peroxidase and superoxide dismutase levels when compared to the control group. We believe that selenium supplementation may be beneficial to prevent the clinical sequelae and recurrence of otitis media

Activity of Brazilian propolis against Aeromonas hydrophila and its effect on Nile tilapia growth, hematological and non-specific immune response under bacterial infection

The effect of the ethanolic extract of propolis (EEP) on Aeromonas hydrophila was analyzed by determination of minimum inhibitory concentration (MIC). Then, the effects of crude propolis powder (CPP) on growth, hemato-immune parameters of the Nile tilapia, as well as its effects on resistance to A. hydrophila challenge were investigated. The CPP (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0%) was added to the diet of 280 Nile tilapia (50.0 ± 5.7 g fish-1). Hemato-immune parameters were analyzed before and after the bacterial challenge. Red blood cell, hematocrit, hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and hydrogen peroxide (H2O2) and nitric oxide (NO) were evaluated. The MIC of the EEP was 13% (v/v) with a bactericidal effect after 24 hours. Growth performance was significantly lower for those fish fed diets containing 2.5 and 3% of CPP compared to the control diet. Differences in CPP levels affected fish hemoglobin, neutrophils number and NO following the bacterial challenge. For others parameters no significant differences were observed. Our results show that although propolis has bactericidal properties in vitro, the addition of crude propolis powder to Nile tilapia extruded diets does not necessarily lead to an improvement of fish health.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Departamento de Produção Animal Faculdade de Medicina Veterinária e Zootecnia/FMVZ Grupo NECTAR Universidade Estadual Paulista/UNESP, Rua Prof. Doutor Walter Mauricio Correa, s/n, Caixa Postal 560, Campus de BotucatuDepartamento de Melhoramento e Nutrição Animal Faculdade de Medicina Veterinária e Zootecnia/FMVZ Grupo AQUANUTRI Universidade Estadual Paulista/UNESP, Rua Prof. Doutor Walter Mauricio Correa, s/n, Caixa Postal 560, Campus de BotucatuDepartamento de Bioestatística Instituto de Biociências de Botucatu Universidade Estadual Paulista/UNESP, R. Prof. Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Junior, Campus de BotucatuDepartamento de Agricultura Faculdade de Ciências Agronômicas/FCA Universidade Estadual Paulista/UNESP, Rua Prof. Doutor Walter Mauricio Correa, s/n, Caixa Postal 560, Campus de BotucatuDepartamento de Produção Animal Faculdade de Medicina Veterinária e Zootecnia/FMVZ Grupo NECTAR Universidade Estadual Paulista/UNESP, Rua Prof. Doutor Walter Mauricio Correa, s/n, Caixa Postal 560, Campus de BotucatuDepartamento de Melhoramento e Nutrição Animal Faculdade de Medicina Veterinária e Zootecnia/FMVZ Grupo AQUANUTRI Universidade Estadual Paulista/UNESP, Rua Prof. Doutor Walter Mauricio Correa, s/n, Caixa Postal 560, Campus de BotucatuDepartamento de Bioestatística Instituto de Biociências de Botucatu Universidade Estadual Paulista/UNESP, R. Prof. Dr. Antônio Celso Wagner Zanin, 250, Distrito de Rubião Junior, Campus de BotucatuDepartamento de Agricultura Faculdade de Ciências Agronômicas/FCA Universidade Estadual Paulista/UNESP, Rua Prof. Doutor Walter Mauricio Correa, s/n, Caixa Postal 560, Campus de BotucatuCNPq: 472389/2009-