2.5. Statistics

Statistical processing of the results was performed with the determination of the sample mean (M), standard error of the mean (S.E.M.), sample median (Med), and intervals of the change. The hypothesis of heterogeneity in the distribution of values across groups of animals was tested using a 3-factor ANOVA test. The significance of paired differences between groups was established using the 2-sided Student’s t-test with Levene’s correction and the nonparametric Mann–Whitney U-test. Differences were considered significant at the level of p < 0.05. The SPSS 20.0 software package (IBM Corporation, Armonk, NY, USA) was used for calculations.