Deltamethrin (DLM) represents one of the most commonly used pesticides. It passes through milk, vegetables, and fruits to humans or through animals (veterinary drugs and feeding on contaminated forage) to milk; it can escape from skin to blood and be secreted in breast milk in lactating women. It is believed to have neurotoxic, nephrotoxic, and hepatotoxic properties. To investigate deltamethrin-induced hepatotoxicity, 64 rats were divided into eight groups. The control group did not receive any treatment. The groups were as follows: D 30 mg DLM/kg body weight (BW) dissolved in corn oil; B 1 mL whey (1010 cfu/mL of Bifidobacterium longum ATCC 15707); S 1 mL whey (0.5 ppm selenium); BS 1 mL whey (1010 cfu/mL of B. longum ATCC 15707 + 0.5 ppm selenium); BD 1 mL whey (1010 cfu/mL of B. longum ATCC 15707 + DLM); SD 1 mL whey (0.5 ppm selenium) + DLM; and BSD 1 mL whey (1010 cfu/mL of B. longum ATCC 15707) + 0.5 ppm selenium + DLM. Results revealed that the manipulation of Bifidobacteria with selenium triggered a significant improvement in AST (U/mL), ALT (U/mL), GSH (mg/g), TNF-α (pg/mL), NF-κB (ng/mL), and BCL2 (ng/mL) from 166.7 ± 6.42, 30.67 ± 0.55, 0.252 ± 0.005, 17.18 ± 0.42, 1.14 ± 0.10, and 1.77 ± 0.06 versus 334.9 ± 4.7, 72.83 ± 2.49, 0.108 ± 0.005, 33.57 ± 0.59, 2.58 ± 0.05, and 1.04 ± 0.04, respectively, compared to DLM group. As well as reduction in histopathological necrosis, congestion, and degradation. Whey beverages fortified with B. longum and selenium implicated a reduction in oxidative stress and histopathological degradation that accomplished DLM toxicity. The utilization of whey (a byproduct of cheese making) is considered a recycling process that supports eco-friendly practices and sustainability, thus encouraging its use as a protective tool in animal feed or manipulation by humans, especially workers in pesticide plants.