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Feathers are the most prevalent agricultural waste generated by chicken farms, polluting the environment and wasting protein resources as a result of the accumulation of large amounts of feathers. Therefore, keratinase-producing microorganisms represent a promising potential technique for the degradation of feather waste. <i>Streptomyces netropsis</i> A-ICA and <i>Bacillus subtilis</i> ALICA, previously isolated from the rhizosphere of desert plants (<i>Larrea tridentata</i> and <i>Prosopis juliflora</i>) respectively, were assessed for their feather-degradation ability. Keratinase activity was optimized using various parameters, including incubation time, pH, temperature, and feather concentration. The maximum keratinase activity of <i>S. netropsis</i> A-ICA and <i>B. subtilis</i> ALICA (113.6 ± 5.1 and 135.6 ± 4.1 U/mL) was obtained at the 5th and 3rd day of incubation with initial pH of 7.0 and 7.5 at 25 and 30 °C, and 1% (<i>w/v</i>) of chicken feather, respectively. Under the optimized conditions, the concentration of soluble protein in the feather hydrolysate reached 423.3 ± 25 and 565.3 ± 7.7 µg/mL, with feathers weight loss of 84 ± 2 and 86± 1.5% by <i>S. netropsis</i> A-ICA and <i>B. subtilis</i> ALICA, respectively. The highest disulphide bond reductase activity reached 10.7 ± 0.4 and 10.96 ± 1.1 U/mL, after five and three days of inoculation with <i>S. netropsis</i> A-ICA and <i>B. subtilis</i> ALICA, respectively. Furthermore, the antioxidant activity of feather protein hydrolysate obtained <i>by S. netropsis</i> A-ICA and <i>B. subtilis</i> ALICA was evaluated using DPPH radical-scavenging activity, which exhibited a significant antioxidant potential with an IC₅₀ value of 0.8 and 0.6 mg/mL. The 3D models of detected keratinases in both strains showed high similarity with subtilisin family. Further, the docking results clarified the importance of GSG and VVVFTP domains in <i>B. subtilis</i> and beta-keratin, respectively. The present study revealed the keratinolytic potential of <i>S. netropsis</i> A-ICA and <i>B. subtilis</i> ALICA in chicken feather degradation, which have potential application value and may be exploited as supplementary protein and antioxidant in animal feed formulations.