SUMMARYThe present work was carried out on 24 coarse-wool Barki and ⅝ Merino–⅜ Barki ram lambs to study the effect of vitamin A supplementation on some skin and wool characteristics. Lambs, at the age of 6 months, were allotted to three groups receiving no vitamin A supplement, 50000 i.u. and 100000 i.u. of vitamin A/head monthly. Blood samples were taken monthly for the assessment of vitamin A in the plasma. It was found that vitamin A in the plasma ranged from 42·4 to 17·50 and from 41·67 to 50·03/ μg/100 ml in the control and treated groups respectively, from the start of the experiment till the end at the age of 17 months.Vitamin A supplementation caused increments in external diameters, of primary and secondary follicles in Barki and primaries in ⅝ Merino, higher than those encountered in internal diameters. An increase in staple length and clean fleece weight of ⅝ Merino and a slight increase in Barki fibre diameter was observed in vitamin-A-supplemented animals.