Spermiogenesis and Ultrastructure of the Spermatozoon of the Liver Fluke Fasciola Gigantica Cobbold, 1856 (Digenea: Fasciolidae), a Parasite of Cattle in Senegal

Abstract

The present paper describes the spermiogenesis and the ultrastructure of the spermatozoon of Fasciola gigantica, as revealed by transmission electron microscopy. Spermiogenesis in F. gigantica begins with the formation of a differentiation zone containing 2 centrioles with associated striated roots and an intercentriolar body between them. Each centriole develops a flagellum. Proximodistal fusion of these flagella with the median cytoplasmic extension gives rise to the spermatozoon. Spermiogenesis in F. gigantica is characterized by the formation of a dorsolateral cytoplasmic expansion, an external ornamentation of the cell membrane, and spinelike bodies. These 3 structures were also observed in the anterior part of the spermatozoon. Our study describes for the first time the simultaneous presence of dorsolateral cytoplasmic expansion, external ornamentation of the plasma membrane, and spinelike bodies in the spermatozoon of a trematode.

Spermiogenesis and sperm ultrastructure of Carmyerius endopapillatus (Digenea, Gastrothylacidae), a parasite of Bos taurus in Senegal

“…The general process of spermiogenesis of Carmyerius endopapillatus is similar to that described in many other digenean species (Burton 1972;Rees 1979;Daddow and Jamieson 1983;Erwin and Halton 1983;Gracenea et al 1997;Li and Wang 1997;Miquel et al 2000;Baptista-Farias et al 2001;Ndiaye et al 2002Ndiaye et al , 2003aNdiaye et al , b, 2004Levron et al 2003Levron et al , 2004aSeck et al 2007). Differentiation zone appears on the side of the spermatid, then a median cytoplasmic expansion and two flagella appear and develop.…”

“…This fusion zone is marked by the presence of four electron dense lines, which appear during the spermiogenesis and persist in the mature spermatozoon. This phenomenon has also been described in many other digenean species: one Haematoloechidae, Haematoloechus medioplexus (Burton 1972), one Didymozoidae, Gonapodasmius (Justine and Mattei 1982a), one Dicrocoeliidae, Corrigia vitta (Robinson and Halton 1982), two Microphallidae, Maritrema linguilla (Hendow and James 1988) and Microphallus primas (Castilho and Barandela 1990), one Haploporidae, Saccocoeliodes godoyi , three Opecoelidae, Opecoeloides furcatus (Miquel et al 2000), Helicometra fasciata (Levron et al 2003), Monorchis parvus (Levron et al 2004a), one Brachylaimidae, Scaphiostomum palaearcticum (Ndiaye et al 2002), one Notocotylidae, Notocotylus neyrai (Ndiaye et al 2003b), two Fasciolidae, Fasciola hepatica (Ndiaye et al 2003a) and Fasciola gigantica (Ndiaye et al 2004), one Paramphistomidae, Paramphistomum microbothrium (Seck et al 2007).…”

Spermiogenesis and ultrastructure of the spermatozoon of Wardula capitellata (Digenea, Mesometridae), an intestinal parasite of the sparid teleost Sarpa salpa in Senegal

“…The flagellar rotation of 90° described in W. capitellata, has been reported in most digeneans: e.g. Haematoloechus medioplexus, Fasciola gigantica, Neoapocreadium chabaudi or Diplodiscus subclavatus (Justine and Mattei 1982, Ndiaye et al 2004, Kacem et al 2010, Bakhoum et al 2011a. However, some recent studies have described flagellar rotations greater than 90°.…”

“…With respect to the distribution of spinelike bodies along the spermatozoon, O. furcatus (Miquel et al 2000) and F. gigantica (Ndiaye et al 2004) show a periodicity of spinelike bodies of 1 µm, P. furcatum (Levron et al 2004b) a periodicity of 0.7 µm, and N. wisniewskii (Quilichini et al 2007a) a periodicity of 0.6 µm. However, due to their irregular distribution no periodicity is observed in W. capitellata as in many other digeneans (see Bakhoum et al 2011a).…”

“…This is the case of Brachylaima aequans, O. furcatus, F. gigantica or D. sub-clavatus (Ždárská et al 1991;Miquel et al 2000;Ndiaye et al 2004;Bakhoum et al 2011a). Other digeneans exhibit two mitochondria, one being located at the level of the ornamented region and the other in the area containing the nucleus.…”