The mammary gland inflammation during the progression of mastitis caused the generation of an accentuated ROS and impairment of antioxidant molecules confirmed in our results by higher MDA, and NO levels (P < 0.001), along with reduction of GSH (P < 0.001), GPx (P < 0.001) catalase (P < 0.01), and SOD (P < 0.001) in mastitic ewes compared to the control non-infected one (Table 3). The gene discussed is SOD1; the disease is mastitis.