wayback disease of young lambs in Basra governorate, Iraq has been detected and diagnosed. Sixty-four local breeds lambs, a week to three months old of both sexes show various clinical manifestations of in-coordination and ataxia. Ten clinically healthy local breeds lambs were used  as controls. All animals were subjected to complete clinical examinations. Diseased lambs showed  different clinical signs such as, lack of coordination with ataxia in hind legs, unable to suck their dams, loss of body weight and apathy, difficulty in standing from  lying down, frequent falls and permanent lying down position. The results concerning the hematological data indicate  Anormocytic normochromic type of anemia with no changes in total and differential leukocytes count. Moreover, biochemical analysis of affected  lambs, and controls indicated a significant decrease in copper compared with controls. Furthermore, a significant increase was detected in ALT, AST and CPK in diseased lambs compared to controls. Histopathological changes of the sciatic nerve of diseased lambs indicated marked edematous fluid in the neural interstia, as well as a marked area of vacuolated neural cells with severe congestion of blood vessels, and an obvious area of vacuolated neural cells. On the other hand, severe perivascular edema in addition to perineural edema was also detected in the brain.