Mycotoxin contamination of feed poses a serious threat to the poultry industry, causing significant economic losses. Traditional adsorbents are ineffective against a wide range of toxins and can reduce the nutritional value of feed. Therefore, developing strategies to activate the animal's endogenous detoxification systems is a pressing issue. This study examined the efficacy of the complex phytogenic supplement (CPS) "Rezovet," containing N-acetylcysteine (NAC), alkylresorcinols, and indole compounds, under experimental mycotoxicosis induced by zearalenone (ZEN) and ochratoxin A (OA). An in vitro experiment on the human hepatoma cell line HepG2 demonstrated that "Rezovet" and its components reliably activate nuclear factor 2 (NRF2), the main regulator of the antioxidant and detoxification response. NRF2 activation was accompanied by an increase in glutathione-S-transferase (GST) gene mRNA expression and its total activity. Furthermore, NAC and indole-3-propionic acid induced a cytoprotective autophagic response in ZEN-exposed cells. Inhibition of autophagy by chloroquine eliminated the protective effect. In an in vivo experiment on Cobb-500 broilers (n=120), the addition of Rezovet (0.5 kg/t feed) to a diet contaminated with ZEN (0.5 mg/kg) and OA (0.25 mg/kg) significantly (p<0.05) reduced liver damage and oxidative stress (a 35% decrease in malondialdehyde levels, a 50% increase in glutathione), while simultaneously increasing GST activity by 40%. Significant improvements in productivity were recorded: livestock survival increased by 4.2%, live weight at 28 days increased by 8.5%, and feed conversion improved by 5.7% compared to the group receiving mycotoxins alone. Metagenomic analysis revealed a 152% increase in the proportion of the commensal bacterium Akkermansia muciniphila in the caecal microbiome and a suppression of urease-producing bacteria (Proteus spp., Klebsiella spp.) in the litter. The synergistic mechanism of action of Rezovet, combining the activation of cellular defense systems and the modulation of microbial communities through mechanisms described in the theory of microbial autoregulation, is discussed. Rezovet is shown to be an effective non-adsorptive agent for the biological detoxification of mycotoxins and microbiome management.