Abstract
This study was carried out on 20 balady sheep belonged to a governmental farm in Alexandria governorate. Ten sheep were suffered from eating of each other's wool (wool eating habit) , weight loss, parakeratosis and different degrees of alopecia . The other 10 sheep were clinically healthy and used as control group. Skin scraping were taken from affected sheep after addition of KOH10%, there was no mite infestation. Fecal samples showed absence of internal parasitic infestation. Two blood samples were collected from each animal. The first blood sample was collected with anticoagulant for hematological analysis while the other was collected without anticoagulant for separation of serum and preforming biochemical analysis. Wool eating sheep showed a significant decrease in hemoglobin and hematocrit without significant changes in erythrocytic and total leucocytic count . Biochemical analysis of serum of affected animals showed significant decrease in serum copper, zinc and iron, total protein and a significant increase in ALP activity than in healthy animals. On the other hand, there was non-significant changes in serum calcium, phosphorus, albumin, glucose, urea, creatinine , ALT and AST activity between diseased and healthy animals. It could be concluded that syndrome of wool eating in sheep is caused mainly by multiple trace element deficiencies particularly copper, iron and zinc.

Key words: wool eating syndrome, trace elements deficiencies, pica, alopecia.