HISTOLOGICAL AND HISTOCHEMICAL STUDY OF EYELID OF NATIVE CATTLE (OX)

The aim of the present work is to study the skin eyelids of native cattle (ox) with special emphasis on the structures that constituted eyelids, detected types of carbohydrates present in these structures and to compare the results with other studied ruminant. Five pairs of eyelids of healthy local ox used for histological and histochemical study. The present works included four areas upper eyelids, lower eyelids , medial canthus and lateral canthus of each eyelid. Eyelids covered internally by palpebral conjunctiva with goblet cells and covered externally by the skin. There was a significant increase on thickness of epidermis and corneal layers of the lower eyelid areas. Dermis included tarsal plate (large amount of collagen fibers, moderate amount of elastic fibers) with many sections of orbicularis muscle and scattered bundle of Müllerś muscle. Eye lash follicle varies in extension and diameter, arranged in double or triple rows. The follicle of eyelashes devoid of arrector pili muscle. They were many types of glands accompanied eyelash follicle, *glands of Zeis (small sebaceous glands) that have a significant difference especially on lower eyelid areas ,** gland of moll; (apocrine sweat glands) that revealed a significant difference in their dimension between lateral canthus , upper eyelid and lower eyelid areas , these glands began near the basement membrane of the upper eyelids . There are modified multilobulated sebaceous glands; Tarsal glands or meibomian glands; that are well developed on the upper eyelids and near the surface of the skin in the same area. Each tarsal gland empty their secretion onto the surface of the eyelid through a duct lined with typical stratified squamous epithelium, ducts vary in extension, they were deeper in the upper eyelids than other studied areas. Histochemistry study revealed a moderate amount of carboxylated glycoprotein in ground substance of eyelids; eye lashes follicle, tarsal gland and gland of moll, while goblet cells revealed strong reaction with carboxylated and neutral glycoproteins. Negative reaction for glycogen, sulphated glycoproteins , sulphated or carboxylated glycosaminoglycans in all studied areas.