Phenotypic plasticity of maleSchistosoma mansonifrom the peritoneal cavity and hepatic portal system of laboratory mice and hamsters

Abstract

Morphometric analysis of Schistosoma mansoni male worms obtained from AKR/J and Swiss mice was carried out. Rodents infected by the intraperitoneal route with 80 cercariae of the schistosome (LE strain) were killed by cervical dislocation at 45 and 60 days post-infection and both peritoneal lavage and perfusion of the portal system were performed for the recovery of adult worms. Characteristics including total body length, the distance between oral and ventral suckers, extension of testicular mass and the number of testes were considered in the morphological analysis. Changes that occurred in S. mansoni recovered from the peritoneal cavity or from the portal system of AKR/J and Swiss mice included total body length and reproductive characteristics. Significant morphometric alterations were also observed when worms recovered from the portal system of both strains of mice were compared with the schistosomes obtained from hamsters (Mesocricetus auratus), the vertebrate host in which the LE strain had been adapted and maintained by successive passages for more than four decades. The present results reinforce the idea that S. mansoni has high plastic potential and adaptive capacity.

Genetic characterisation and phylogenetic status of whipworms (Trichuris spp.) from captive non-human primates in China, determined by nuclear and mitochondrial sequencing

“…What is even more noteworthy is that phenotypic plasticity is particularly apparent among parasitic helminths because their range of hosts, origins and developmental stages can facilitate very different morphological and physiological characters useful for adaption and survival [ 58 ]. For example, within worms, Mati and colleagues [ 59 ] found that adult males of the human parasite Schistosoma mansoni maintained in AKR/J and Swiss mice, respectively, had significant morphometric changes in the total body length and reproductive characteristics (including the extension of testicular mass and number of testes) and that these morphometric alterations were also observed when compared to S. mansoni obtained from hamsters ( Mesocricetus auratus ), the host in which the parasite had been adapted and maintained for decades.…”

DNA profiling reveals Neobenedenia girellae as the primary culprit in global fisheries and aquaculture

“…The CytB neighbor-joining analysis shows significant substructuring in N. girellae , which may account for the variable morphology noted by Whittington and Horton (1996). Morphological variation can be due to epigenetic factors which influences the phenotype expressed depending on the particular environment being experienced (Agrawal 2001; Mati et al, 2014; Olstad et al, 2009; Via et al, 1995). The flexibility displayed by these parasites makes the identification of species solely through morphological means considerably challenging (Barcak et al, 2014; Bickford et al, 2006).…”

Somatic Dimorphism in Cercariae of a Bird Schistosome

“…The use of experimental and/or genotyping molecular methods enabled phenotypic variation studies also in clonal cercariae such as output rates, activity and survival patterns, photo- and geotaxis behavior, or infection success [ 26 , 27 , 28 , 29 , 30 , 31 , 32 ]. As mammalian and bird schistosomes serve as model organisms for studying various biological and ecological aspects of parasitism and host–parasite interactions, research on their polymorphism is more advanced than in other trematode groups, focusing on host-induced morphometrical alterations (e.g., [ 33 , 34 ]), genetic diversity of different developmental stages (e.g., [ 35 , 36 , 37 , 38 , 39 ]), or a compatibility polymorphism in snail-schistosome interactions (reviewed in [ 40 , 41 ]). As far as we are aware, only one study to date has detected somatic dimorphism in larval schistosomes (cercariae of Schistosoma mansoni ) during long-term breeding of the snail host ( Biomphalaria glabrata ) under laboratory conditions [ 42 ], but a similar case has not yet been reported for schistosome larvae infecting birds, originating from naturally infected snails.…”