Pakistan Veterinary Journal (Apr 2013)
Morphology of the Lacrimal Gland and Superficial Gland of the Third Eyelid of Roe Deer (Capreolus Capreolus L.)
Abstract
This study on the lacrimal gland (LG) and the superficial gland of the third eyelid (SGTE) was conducted on 21 sexually mature Roe deer (11 males and 10 females). The research material was obtained from Roe deer shot by the Hunting Association during their prescribed hunting season. The shape and topography of the glands are described macroscopically. The LG has a triangular shape in all the investigated individuals and it is located in the dorsolateral angle of the orbit, between the tendons of the dorsal rectus and the lateral rectus muscles of the eyeball. The SGTE is oval in shape and it is located between the medial rectus muscle and the ventral rectus muscle of the eyeball and it is partially covered with the ventral oblique muscle of the eyeball. The SGTE is situated around the cartilage of the third eyelid During histological and ultrastructural analyses using light and transmission electron microscopy, it was established that the LG is a tubulo-acinar gland. Histochemical examination demonstrates that excretory cells are in general PAS-negative and Alcian blue pH 2.5-negative, and thus this gland can be regarded as a serous gland. The SGTE exhibits also a tubulo-acinar morphology. The histochemical study showed that the SGTE is of a combined nature, i.e. with serous cells (PAS-negative and Alcian blue pH 2.5-negative), mucous (PAS-positive and Alcian blue pH 2.5-positive) and seromucous cells (PAS-positive and Alcian blue pH 2.5-positive). Upon electron microscopic examination, LG and SGTE secretory cells exhibited a similar ultrastructure appearance, with secretory cells tightly filled with intracytoplasmatic secretory granules. Neither the body size nor gender had a significant influence on the size of the LG and the SGTE (t-test: P>0.05). The ultrastructure and function of the investigated eyeball’s glands in Roe deer was similar to those observed in other species, like cattle, camel and bison.
