The spermatozoal ultrastructure of the Chinese mitten crab (Eriocheir Sinensis)

Abstract

Background:The Chinese mitten crab (Eriocheir sinensis) is an economically important aquatic species in China. The artificial breeding crabs are also increasing in number day by day. However, knowledge about spermatozoal organization of the crab is still very limited.Aims and Objectives:In the present study, the spermatozoal ultrastructure of the E. sinensis is illustrated for improving artificial breeding technique.Materials and Methods:The spermatozoa are observed by light microscopy and transmission electron microscopy.Results:Spermatozoa are located in the lumen of seminiferous tubules. The spermatocytes and spermatids are observed in the wall of seminiferous tubules. The spermatophores are both present in the lumen of vas deferens and seminal vesicles. A mature spermatozoon consists of a central electron dense acrosome and a peripheral electron lucent nucleus within structures-organelles complex. The acrosome is divided into three zones, including inner acrosome zone, outer acrosome zone and zonal texture. The centre of acrosome is the perforatorium within parallel arranged perforatorial tubules along vertical axis. The highest electron dense operculum surrounds the head side of perforatorium.Conclusion:The ultrastructure of spermatozoa of E. sinensis is illustrated. In particular, the outermost part of the acrosome appears as concentric circles and is described as zonal texture.

Internal anatomy and ultrastructure of the male reproductive organization of the Sesarmid crab Muradium tetragonum (1798)—(Decapoda: Brachyura)

“…Furnishings of the study by (Jamieson and Tudge 1990) reported similar sub‐shperoidal acrosome of sperm with strong depressions in Porunuspelagicus and Macropodia longirostris respectively. Acrosome includes three concentric zonations; electron‐dense inner acrosomal layer, intermediate layer with low electron density and an outer acrosomal zone being in accordance to the pattern present in Eriocheir sinensis (Zeng et al, 2019), Pinnotheridae (Becker et al, 2011), M . messor , M .…”

“…Furnishings of the study by (Jamieson and Tudge 1990) reported similar subshperoidal acrosome of sperm with strong depressions in Porunuspelagicus and Macropodia longirostris respectively. Acrosome includes three concentric zonations; electrondense inner acrosomal layer, intermediate layer with low electron density and an outer acrosomal zone being in accordance to the pattern present in Eriocheir sinensis (Zeng et al, 2019), Pinnotheridae (Becker et al, 2011), M. messor, M.brachydactyla (Simeó et al, 2009), P. plicatum (Ganapiriya, 2012) and Cardisoma guanhumi (Benetti et al, 2013). Thus, the sub-spheroidal shape and the concentric zonation of M. tetragonum confirms its phylogenetic relationship with heterotreme-thoracotreme stock.…”

“…Noticed electron-dense complex envelope of the sperm nucleus shall attribute to the combination of the plasma membrane and nuclear membrane, aligning with other brachyurans (Simeó et al, 2009). Nuclear arms or extensions observed in M. tetragonum, encompass chromatin as demonstrated in Heterotremta and Thoracotremata, (Jamieson, 1994) and resembling the pattern in Eriocheir sinensis (Zeng et al, 2019). Moreover, depleted cytoplasm spotted at the base of the perforatorium favours the results of (Jamieson and Tudge 1990) in Neodorippe astute and (Simeó et al, 2009) in M. brachydactyla.…”

“…Nuclear arms or extensions observed in M . tetragonum , encompass chromatin as demonstrated in Heterotremta and Thoracotremata, (Jamieson, 1994) and resembling the pattern in Eriocheir sinensis (Zeng et al, 2019). Moreover, depleted cytoplasm spotted at the base of the perforatorium favours the results of (Jamieson and Tudge 1990) in Neodorippe astute and (Simeó et al, 2009) in M .…”

Artificial Insemination of Mud Crab, Scylla olivacea

“…4b). The spike has been described in many crab species as the nuclear arm and the black dot as the acrosomal cap, both were parts of the AR process (Wang et al 2015;Zeng et al 2019). Under TEM of this study, the sperm had an oval shape with acrosomal components being composed of the acrosomal cap and acrosomal zone that occupied most area of the sperm, while the decondensed nucleus formed a cup-shaped structure around its posterior periphery (Fig.…”