The considerable change in the expression configuration of antioxidant (SOD3, CAT, GPX, ATOX1 and COX18) and immunological (IL-1α, IL-1β, IL-6, IL-10, TNFα, NCF4, NFKB, TMED, FCAMR and iNOS) indicators in rams with arthritis may be explained by the previously described factors. The gene discussed is CAT; the disease is Arthritis.