Female Reproductive System

Abstract

The reproductive system of Didelphis (Fig. 16) consists of two ovaries, oviducts, uteri, cervices, a median vaginal apparatus (fused vaginal culs-de-sac), two lateral vaginal canals, a urogenital sinus and urogenital strand tissue (Tyson 1698; Blainville 1818; Meigs 1847; Pappenheim 1847; Nelson and Maxwell 1942; Morgan 1946a,b,c; Hartman 1952; Lierse 1965). The ovaries are typically mammalian and the normal (Martínez-Esteve 1942) and abnormal (Hartman 1927) adult morphological features have been described. Stefenson et al. (1981) described the adrenergic innervation of the opossum ovary and noted that nerve terminals are present in the follicular walls and often show a greater density at this location than in the surrounding cortical stroma. The oviducts follow a torturous course in Didelphis, the loops of which are anchored firmly together by adjacent connective tissue. The lining epithelium of the oviduct consists of a simple ciliated columnar epithelium which lies on a delicate lamina propria (Anderson 1928). The last few millimeters of the oviduct exhibit a concentration of well developed mucosal glands (Anderson 1928). Secretions from these glands are thought to contribute to the shell membrane which surrounds the ovum and developing zygote of Didelphis. The supporting wall of the oviducts consists of outer longitudinal and inner circular layers of smooth muscle (Hartman 1924a). Like the oviducts, the uteri and cervices are paired and completely separate. The uteri consist of an outer muscular myometrium and an inner glandular mucosa, the endometrium. The myometrium consists primarily of an outer longitudinal and an inner circular layer of smooth muscle.