Structure of the Ovary and Mode of Oogenesis in a Freshwater Crayfish, Procambarus clarkii (Girard)

Abstract

The adult ovary was examined in a freshwater crayfish, Procambarus clarkii, to clarify the ovarian structure and the mode of oogenesis. A Y-shaped ovary consisting of a pair of anterior ovarian sacs and a single posterior ovarian sac was located in the cephalothorax, on the dorsal side of the stomach. An oviduct connected each of the posterior ends of the paired anterior ovarian sacs with the genital pore on the coxa of the 6th appendage. The wall of the ovarian sacs, consisting of a layer of the ovarian epithelium, folded inwards to form a number of oogenetic pouches of various sizes. Each oogenetic pouch contained one egg or large oocyte, vitellogenic or previtellogenic, sometimes followed by a few early previtellogenic oocytes in the oogenetic pouch lumen. Germaria containing oogonia, very early previtellogenic oocytes and somatic interstitial cells were located in the ovarian epithelium near the bases of the oogenetic pouches. In a cross-section of the ovarian sac, the germaria were concentrated in the center of the ovarian sac as a central germarial cluster. An early previtellogenic oocyte beginning to grow left its germarium and raised the ovarian epithelium to form a new oogenetic pouch, in which it remained until mature. Mature eggs were ovulated from the oogenetic pouches into the central ovarian lumen, transferred into the oviducts, and oviposited through the genital pores. The female reproductive system was surrounded wholly and tightly by a thin muscular sheath, which has often been mistaken as the ovarian epithelium in some decapod crustaceans.

Gonad development in females of fiddler crab Uca rapax (Crustacea, Brachyura, Ocypodidae) using macro and microscopic techniques

“…In the histological analyses of the female's ovaries, the modifications observed in the oocytes during the process of gonad maturation are similar to the descriptions in the literature for other females of decapod crustaceans (ADIYODI & SUBRAMONIAN, 1983;LÓPEZ et al, 1997;OLIVEIRA et al, 1999;ANDO & MAKIOKa, 1998;ELORZA & DUPRÉ, 2000). The similarities are specially found in the morphological changes in the reproductive cells, and also in the presence and arrange of follicle cells during the process of ovary maturation.…”

“…The description of cellular stages agrees with the characteristics described by ADIYODI &SUBRAMONIAN (1983) andMEUSY &CHARNIAUX-COTTON (1984). These characteristics were posteriorly identified in other species of decapods (LÓPEZ et al, 1997, ANDO & MAKIOKA, 1998ELORZA & DUPRÉ, 2000).…”

“…Most of the papers dealing with the determination of the onset of the sexual physiological maturity or histological maturity, taking into account the degree of gonad development (COSTA & NEGREIROS-FRANSOZO, 1998;PINHEIRO & FRANSOZO, 1998;LÓPEZ-GRECO & RODRÍGUEZ, 1999a;SANTOS & NEGREIROS-FRANSOZO, 1999;CASTIGLIONI & SANTOS, 2001;SWINEY & SHIRLEY, 2001;FLORES et al, 2002;CASTIGLIONI & NEGREIROS-FRANSOZO, 2006 among others). However, studies of histological description of gonads are less common (CRONIN, 1947;ADIYODI & SUBRAMONIAN, 1983;MEUSY & CHARNIAUX-COTTON, 1984;WENNER et al, 1987;KROL et al, 1992;LÓPEZ et al, 1997;ANDO & MAKIOKA, 1998), the majority being on Caridea and Penaeoidea (RODRÍGUEZ, 1985;TAN-FERMIN & PUDADERA, 1989;QUINITIO & MILLAMENA, 1992;MORAES, 1994;QUINTERO & GRACIA, 1998;OLIVEIRA et al, 1999;PALACIOS et al, 1999;SAKAJI et al, 2000;SAKAJI, 2001;MOSSOLIN &BUENO, 2002 andDUMONT &D'INCAO, 2004).…”

Morphological and histochemical examination of male and female gonads in Homarus gammarus (L. 1758)

“…The ovary wall of H. gammarus is not as thick as H. americanus and is as thin as that in C. quadricarinatus and P. clarkii, and it is formed by prolonged straight muscle fibers. A. leptodactylus does not contain any muscle in the ovary wall [20][21][22][23]. The oviduct epithelium in H. gammarus produces a secretion which gives a PAS positive reaction from its apical surface to the lumen but it does not stain with Bromophenol blue.…”

Intersex females in the red claw crayfish, Cherax quadricarinatus (Decapoda: Parastacidae)

“…From a histomorphological point of view, the ovary of C. quadricarinatus females and intersexes belongs to the "mandibulate type" (Krol et al 1992, Ando andMakioka 1998). It is a sac-like structure where the proliferative zone, containing mainly oogonia, is located in the center of the gonad next to the ovarian lumen, while oocytes are surrounding the nests of oogonias in a more peripheral position.…”