Abstract
Oxidative stress has been implicated in growth retardation and impairment in poultry, whereas selenium yeast (SeY), a bioavailable organic selenium source, can exert potent antioxidant effects in the body. The study investigated the protective effects of dietary supplementation with SeY against diquat (DQ)-induced oxidative damage in oviductal magnum of hens. Experimental results showed that dietary supplementation with SeY effectively alleviated DQ-induced histopathological alterations, including mucosal structural damage and reduced epithelial cell proliferation in the oviductal magnum. Specifically, dietary supplementation with SeY inhibited DQ-induced oxidative stress by upregulating Nrf2 and HO-1 expression levels, enhancing the activities of antioxidant enzymes, such as catalase (CAT) and total superoxide dismutase (T-SOD), and reducing the concentration of malondialdehyde (MDA). Furthermore, SeY supplementation inhibited DQ-induced mucosal cell apoptosis by regulating the expression of apoptosis-related genes and proteins (Bax, Bcl-2, and Caspase3), as well as inflammation-related factors (NF-κB and p53). Concurrently, it restored proliferative capacity of mucosal cells by promoting the expression of the proliferation-related protein PCNA. These findings signify that dietary supplementation with SeY effectively safeguards the oviductal magnum against DQ-induced damage through multi-target mechanisms involving oxidative homeostasis, apoptosis inhibition, and cell proliferation promotion. This study provides a solid theoretical foundation for future research aimed at safeguarding the reproduction health of female poultry exposed to agricultural pesticides.