Evaluation of oxidative stress in healthy cattle submitted to ozone therapy by rectal insufflation using increasing doses

• Grant number: 21/07928-5
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2021
• Effective date (End): September 30, 2022
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal researcher: Breno Fernando Martins de Almeida
• Grantee: Matheus Nogueira de Morais
• Home Institution: Faculdades Integradas de Ourinhos (FIO). Fundação Educacional Miguel Mofarrej. Ourinhos , SP, Brazil

Abstract

Ozone therapy induces transient and controlled oxidative stress in the organism, inducing an antioxidant response, as demonstrated in other species. However, very little is known about how ozone therapy affects the oxidative stress parameters, especially in cattle. This type of assessment is necessary to understand the pathophysiological mechanisms that ozone therapy causes in the organism, an initial item for this therapy to be recommended as safe and effective. In this context, this project aims to evaluate the oxidative stress parameters of healthy cattle submitted to ozone therapy by rectal insufflation. For this purpose, 10 healthy adult cattle will undergo 8 applications of ozone by rectal insufflation twice a week at a dose of 0.05 (week 1), 0.1 (week 2), 0.15 (week 3), 0.2 (week 4) mg of ozone/kg, with a collection of samples for assessment of oxidative stress up to 10 weeks after the start of therapy. Additionally, another 10 healthy cattle will constitute the control group and will have samples obtained at the same times as the treated group. Oxidative stress will be determined by total antioxidant capacity (TAC) by four methods: by reduction of ABTS cation (TAC-ABTS), reduction of ABTS cation associated with peroxidase (TAC-ABTS+HRP), iron reduction (TAC-FRAP), and cupric (TAC-CUPRAC); in addition to the determination of total oxidizing capacity (TOC), lipid peroxidation by thiobarbituric acid reactive substances (TBARS) and uric acid and albumin antioxidants. The variables will be tested for normality and homoscedasticity and the differences between moments will be verified by ANOVA with repeated measures and Tukey's post-test or Friedmann with Dunn's post-test, while the differences between groups at each moment will be verified by the t or Mann-Whitney test. Correlations will be determined by Pearson or Spearman coefficients. Analyzes will be considered significant when p<0.05. (AU)