Protective effects of polysaccharide of Atractylodes macrocephala Koidz and Jiawei Si-jun-zi Decoction on gut health and immune function in cyclophosphamide-treated chicks

The gut serves not only as digestive but also as critical immune organ, playing a vital role in maintaining the growth performance and immune function of poultry. Atractylodes macrocephala Koidz (AMK) is known for its antioxidant, anti-inflammatory and immunomodulatory properties. This study utilized a Cyclophosphamide (CTX)-induced gut injury model to explore the effects of Polysaccharide of Atractylodes macrocephala Koidz (PAMK) and the Jiawei Si-jun-zi Decoction (JSD) on alleviating gut injury and modulating immune function. The experimental results demonstrated that CTX significantly reduced the average daily gain (ADG) and antioxidant capacity of broiler chicks, disrupted intestinal barrier function, and induced gut microbiota dysbiosis. However, supplementation with PAMK and JSD significantly improved ADG, enhanced antioxidant enzyme activity, alleviated oxidative stress, and upregulated the expression of barrier-related genes such as ZO-1 and Occludin. Additionally, PAMK and JSD significantly increased anti-inflammatory cytokines, including IL-10 and TGF-β, improved gut microbiota diversity, enriched beneficial microbial populations, and restored the microbiota balance disrupted by CTX. These findings suggest that PAMK and JSD effectively mitigate CTX-induced intestinal injury by regulating the antioxidant system, strengthening intestinal barrier function, and restoring gut microbiota structure. This study provides a scientific basis for the development of safe and effective feed additives and proposes a novel strategy to reduce antibiotic use in poultry farming.