Preliminary Anatomical and Histological Study of Lacrimal Gland in Lori Sheep

The eye is a complex and highly developed organ which collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable lens to form an image on retina where this image is converted into a set of electrical signals transmitted to the brain. The eyes are protected in the skull by a bony box called the eye socket (orbit). The wall of this eyeball consists of three layers which have different tasks in the anterior and posterior halves of the organ [1]. One of accessory structures of the eye is the lacrimal apparatus which located superiorly and laterally to each eyeball. Each lacrimal apparatus consists of the lacrimal gland, canalicule, lacrimal sac and naso lacrimal duct [2]. The lacrimal glands are responsible for production of tears which flow over the conjunctiva [1]. The lacrimal gland is responsible for production and secretion of tears which clean and nourish the cornea and help to maintain its health. In many species, the main fraction of tears is produced by lacrimal glands. In cattle and wild buffalo, no difference is observed between left and right glands. Moreover, in these animals no sexual dimorphism is evident in the case of the lacrimal gland [3]. There are adequate researches documenting the anatomy and histology of lacrimal glands in human and some other mammals. In all investigated species, the lacrimal gland has presented more or less a similar histological structure and is a mixed gland consisting of tubulo-acinar units [4]. There is a lack of literature on the lacrimal gland in this breed of sheep, our research will contribute to the comparative anatomy and histology and help to understanding the structure of this gland. Moreover, many chemical components in the tear have been documented [5-9]. In current study, the anatomical and histological structure of these glands Lori sheep is scrutinized.