A comparative study of the ultrastructural characteristics of the mature spermatozoa of two fellodistomids Tergestia clonacantha and T. laticollis and contribution to the phylogenetic knowledge of the Gymnophalloidea.

The ultrastructure of the mature spermatozoa of Tergestia clonacantha and T. laticollis collected from the digestive tracts of fishes from New Caledonia is described using transmission electron microscopy and compared to that of related species. The spermatozoa of the two species exhibit the general pattern described in most digeneans, namely two axonemes with the 9 + "1" pattern of the Trepaxonemata, nucleus, mitochondrion, cortical microtubules, an external ornamentation of the plasma membrane, spine-like bodies and granules of glycogen.

Spermatological characteristics of Sclerodistomoides pacificus (Digenea, Sclerodistomoididae) a parasite of the flying fish Cheilopogon pinnatibarbatus (Teleostei, Exocoetidae).

Sclerodistomoides pacificus is the only species described now in Sclerodistomoididae. We present in this paper the first ultrastructural data of the mature spermatozoon of a species from the genus Sclerodistomoides. Adult specimens of S.

Ultrastructure of mature spermatozoa of three Bucephalidae (Prosorhynchus longisaccatus, Rhipidocotyle khalili and Bucephalus margaritae) and phylogenetic implications.

We describe here the mature spermatozoa of three species of bucephalids, namely Bucephalus margaritae, Rhipidocotyle khalili and Prosorhynchus longisaccatus. This study provides the first ultrastructural data on the genera Bucephalus and Rhipidocotyle and enabled us to confirm the model of the mature spermatozoon in the Bucephalinae. The spermatozoon exhibits two axonemes with the 9 + "1" pattern of the Trepaxonemata, one of which is very short, lateral expansion, external ornamentation of the plasma membrane located in the anterior extremity of the spermatozoon and associated with cortical microtubules, spine-like bodies, a mitochondrion, and a nucleus.

Genetic and morphological characterization of Thysaniezia tapeworms from cattle and sheep in Senegal.

Genetic and morphological diversity of Thysaniezia tapeworms from cattle and sheep in Senegal was investigated using light and scanning microscopic observations and molecular analysis based on mitochondrial cytochrome c oxidase subunit 1 (cox1) and nuclear small subunit ribosomal RNA gene (SSU rDNA). A total of 52 adult tapeworms were collected from sheep and cattle. Although the tapeworms of the two hosts were morphologically very close, phylogenetic analysis based on cox1 and SSU rDNA gene sequences showed that they were divided into two clades corresponding each to a host.

Advances in Spermatological Characters in the Digenea: Review and Proposal of Spermatozoa Models and Their Phylogenetic Importance.

The wide biodiversity and economic importance of digeneans have motivated a great deal of research in the last decade, focussing on their phylogenetic positions. Molecular research was instrumental for our understanding of phylogeny in the Digenea, but spermatological studies have also provided many results, which are potentially useful for phylogeny; however, the complete spermatological data set has never been reviewed in a whole phylogenetic perspective. Spermatological data are now available for more than 100 species, belonging to 15 superfamilies and 46 families.

Ultrastructural characteristics of the mature spermatozoon of the digenean Sclerodistomum italicum (Stossich, 1893) (Hemiuroidea, Sclerodistomidae) intestinal parasite of Hypocanthus amia (Teleostei, Carangidae).

The mature spermatozoon of Sclerodistomum italicum is filiform, tapered at both ends and shows the following features: 2 axonemes of the 9+"1" pattern of the Trepaxonemata, mitochondrion, nucleus and parallel cortical microtubules. The specific features of the spermatozoon of S. italicum include the simultaneous presence of two types of extramembranous ornamentations, the presence of short cortical microtubules in the anterior part of the spermatozoon and the presence of only one bundle of cortical microtubules in the median part of the spermatozoon.

Spermatozoon ultrastructure in two monorchiid digeneans.

Spermatological characteristics of species from two monorchiid genera, Opisthomonorchis and Paramonorcheides, have been investigated, for the first time, by means of transmission electron microscopy. The ultrastructural study reveals that the mature spermatozoon of Opisthomonorchis dinema and Paramonorcheides selaris share several characters such as the presence of two axonemes of different lengths showing the 9+"1" pattern of the Trepaxonemata, a nucleus, two mitochondria, two bundles of parallel cortical microtubules, external ornamentation of the plasma membrane, spine-like bodies, granules of glycogen and similar morphologies of the anterior and posterior extremities. The slight differences between the male gamete of O.

Prevalence and Scanning Electron Microscopic Identification of Anoplocephalid Cestodes among Small Ruminants in Senegal.

This study was undertaken to determine the prevalence of anoplocephalid cestodes in sheep and goats in Senegal. Intestines of 462 sheep and 48 goats were examined; 47.4% of sheep and 6.

The host specificity of ape malaria parasites can be broken in confined environments.

Recent studies have revealed a large diversity of Plasmodium spp. among African great apes. Some of these species are related to Plasmodium falciparum, the most virulent agent of human malaria (subgenus Laverania), and others to Plasmodium ovale, Plasmodium malariae and Plasmodium vivax (subgenus Plasmodium), three other human malaria agents.

Impact of Annual Praziquantel Treatment on Urogenital Schistosomiasis in a Seasonal Transmission Focus in Central Senegal.

In Sub-Saharan Africa, urogenital schistosomiasis remains a significant public health problem, causing 150.000 deaths/year with approximately 112 million cases diagnosed. The Niakhar district is a disease hotspot in central Senegal where transmission occurs seasonally with high prevalences.

Ultrastructural study of the spermatozoon of Hemiurus appendiculatus (Digenea, Hemiuroidea, Hemiuridae), a parasite of Boops boops (Pisces, Teleostei, Sparidae) off Senegal.

The mature spermatozoon of Hemiurus appendiculatus exhibits the general pattern described in most of the digenean namely, two axonemes of the 9 + "1" pattern of the Trepaxonemata, a nucleus, a filiform mitochondrion, external ornamentations of the plasma membrane and parallel cortical microtubules located on one side of the spermatozoon. In this study, we show for the second time in a digenean spermatozoon the presence of microtubules of the second axoneme associated each in a short length with an external ornamentation, seven cortical microtubules, a terminal bulge in the anterior spermatozoon extremity separate from the remainder of the spermatozoon by a transverse constriction and the simultaneous presence of the external ornamentation of the plasma membrane with a filamentous ornamentation. The external ornamentations have a differentiated distribution, cover almost the anterior region of the spermatozoon, are more abundant around the first axoneme and extend backwards over a short distance around the second axoneme.

Haemosporidian Parasites of Antelopes and Other Vertebrates from Gabon, Central Africa.

Re-examination, using molecular tools, of the diversity of haemosporidian parasites (among which the agents of human malaria are the best known) has generally led to rearrangements of traditional classifications. In this study, we explored the diversity of haemosporidian parasites infecting vertebrate species (particularly mammals, birds and reptiles) living in the forests of Gabon (Central Africa), by analyzing a collection of 492 bushmeat samples. We found that samples from five mammalian species (four duiker and one pangolin species), one bird and one turtle species were infected by haemosporidian parasites.

[Living the aging in Senegal Perceptions/representations and coping strategies of persons of age three: results of investigations retrospective].

In Senegal, due to the young age of the population (60%) the concerns of the old tend to be put in the background. And yet, problems related to old age are a reality. These problems come up not in terms of demography (the old represent only 4.

First spermatological study in the Atractotrematidae (Digenea, Haploporoidea): the case of Atractotrema sigani, intestinal parasite of Siganus lineatus.

The ultrastructural organization of the mature spermatozoon of the digenean Atractotrema sigani (from Siganus lineatus off New Caledonia) was investigated by transmission electron microscopy. The male gamete of A. sigani exhibits the general morphology described in digeneans with the presence of two axonemes of different lengths showing the 9 + "1" pattern of the Trepaxonemata, a nucleus, two mitochondria, two bundles of parallel cortical microtubules, external ornamentation, spine-like bodies and granules of glycogen.

Study of the snail intermediate hosts of urogenital schistosomiasis in Niakhar, region of Fatick, West central Senegal.

Background: Schistosoma haematobium is the most widespread schistosome species in Senegal and occurs in several regions of the country especially in the Sudan-Sahelian zone. The aims of the study were i) to determine the freshwater species ii) to ascertain the role of the identified snail species in the transmission of S. haematobium and iii) to study the impact of drought on the snails.

Ultrastructural characters of the spermatozoa in Digeneans of the genus Bianium Stunkard, 1930 (Digenea, Lepocreadiidae) parasites of fishes: a comparative study of Bianium plicitum and Bianium arabicum.

We present in this paper the first ultrastructural study of the spermatozoon of species of the genus Bianium Stunkard, 1930, namely Bianium plicitum and Bianium arabicum belonging to the family Lepocreadiidae. Specimens are parasites of the tetraodontid teleosts Lagocephalus laevigatus caught in the Atlantic Ocean and Lagocephalus sceleratus caught in Pacific Ocean, respectively. Live worms were fixed and processed for transmission electron microscopy.

Efficacy of praziquantel against urinary schistosomiasis and reinfection in Senegalese school children where there is a single well-defined transmission period.

Background: Human schistosomiasis is a significant health problem in Sub-Saharan Africa. In Niakhar, West central Senegal, the transmission of S. haematobium occurs seasonally between July and November.

Malaria-like symptoms associated with a natural Plasmodium reichenowi infection in a chimpanzee.

Although Plasmodium infections have never been clearly associated with symptoms in non-human primates, the question of the pathogenicity of Plasmodium parasites in non-human primates still remains unanswered. A young chimpanzee, followed before and after release to a sanctuary, in a semi-free ranging enclosure located in an equatorial forest, showed fever and strong anaemia associated with a high Plasmodium reichenowi infection, shortly after release. The animal recovered from anaemia after several months despite recurrent infection with other Plasmodium species.

Diversity of malaria parasites in great apes in Gabon.

Background: Until 2009, the Laverania subgenus counted only two representatives: Plasmodium falciparum and Plasmodium reichenowi. The recent development of non-invasive methods allowed re-exploration of plasmodial diversity in African apes. Although a large number of great ape populations have now been studied regarding Plasmodium infections in Africa, there are still vast areas of their distribution that remained unexplored.

Genetic characterization of Moniezia species in Senegal and Ethiopia.

Genetic diversity of Moniezia spp. from domestic ruminants in Senegal and Ethiopia was investigated based on the nucleotide sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) and nuclear small subunit ribosomal RNA gene (SSU rDNA). A total of 64 adult tapeworms were collected from sheep, goat and cattle, and the tapeworms from cattle were all morphologically identified as Moniezia benedeni.

Ultrastructural study of sperm cells in Acanthocolpidae: the case of Stephanostomum murielae and Stephanostomoides tenuis (Digenea).

The mature spermatozoa of Stephanostomum murielae and Stephanostomoides tenuis are described by transmission electron microscopy. They present several ultrastructural features previously reported in other digeneans. Their spermatozoa possess two axonemes of different length showing the 9 + '1' trepaxonematan pattern, four attachment zones, two mitochondria (with an anterior moniliform one in S.

Neomultitestis aspidogastriformis Bray and Cribb, 2003 (Digenea, Lepocreadiidae): mature spermatozoon and sperm morphologies in the Lepocreadioidea.

Spermatological characteristics are described for the first time in the genus Neomultitestis Machida, 1982, belonging to the family Lepocreadiidae Odhner, 1905. Adult Neomultitestis aspidogastriformis were collected from the digestive tract of Platax teira, caught off New Caledonia. The mature spermatozoon of N.

Collyricloides massanae (Digenea, Collyriclidae): spermatozoon ultrastructure and phylogenetic importance.

The spermatological characteristics of Collyricloides massanae (Digenea: Collyriclidae), a parasite of Apodemus sylvaticus caught in France, were studied by means of transmission electron microscopy. The mature sperm of C. massanae presents two axonemes of different lengths with the 9 + "1" pattern of the Trepaxonemata, two bundles of parallel cortical microtubules, external ornamentation of the plasma membrane, spine-like bodies, one mitochondrion, a nucleus and granules of glycogen.

Ultrastructural characters of the spermatozoa in Digeneans of the genus Lecithochirium Lühe, 1901 (Digenea, Hemiuridae), parasites of fishes: comparative study of L. microstomum and L. musculus.

This study provides the first ultrastructural data of spermatozoa in the genus Lecithochirium. The spermatozoa of L. microstomum (from Trichiurus lepturus in Senegal) and L.

Prevalence and intensity of urinary schistosomiasis among school children in the district of Niakhar, region of Fatick, Senegal.

Background: Urinary schistosomiasis is a parasitic disease that exists in all regions of Senegal. It is a major public health issue in this country. This study was carried out to determine the prevalence and intensity of this parasitosis in 12 villages of Niakhar (Fatick, Senegal).