The most common reason to assess the trace mineral status of ruminants is because performance is below expectation. Accordingly, the assessment is done to determine the presence or prevalence of nutrient deficiencies (or toxicities) within a population. Assessment also is done to evaluate efficacy of dietary supplementation or to compare available supplements. The aim of this study was to assessment of serum values of copper in sanjabian ewes in ilam province of Iran. In this study, 200 blood serum, belonging to 200 sanjabian sheep aging between 2-2.5, growing in the pasture conditions were used as a material in autumn and winter. The sera were extracted from the blood taken, and kept in the deep freeze in -20°C, until they are analyzed. The copper analyses in the serum were made with spectrophotometric method by Randox kit. The values found were evaluated by “t test”. Based on data and t-test results revealed that copper serum mean value in autumn and winter were 0.325±0.01and 0.928±0.61 ppm respectively which is suggests that there is a significant difference among copper serum levels in two season (p<0.001). It has been thought that this study will fulfill an important gap, because of not to be present the normal value of serum copper belonging to the sanjabian races. It is known that the excess and insufficiency of trace elements cause some disorders and decrease in production. So in order to search the effects of these substances, the normal values should be known.
