Rivista e Edizione

Volume 59 (2022): Edizione 2 (June 2022)

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Volume 58 (2021): Edizione 2 (June 2021)

Volume 58 (2021): Edizione 1 (March 2021)

Volume 57 (2020): Edizione 4 (December 2020)

Volume 57 (2020): Edizione 3 (September 2020)

Volume 57 (2020): Edizione 2 (June 2020)

Volume 57 (2020): Edizione 1 (March 2020)

Volume 56 (2019): Edizione 4 (December 2019)

Volume 56 (2019): Edizione 3 (September 2019)

Volume 56 (2019): Edizione 2 (June 2019)

Volume 56 (2019): Edizione 1 (March 2019)

Volume 55 (2018): Edizione 4 (December 2018)

Volume 55 (2018): Edizione 3 (September 2018)

Volume 55 (2018): Edizione 2 (June 2018)

Volume 55 (2018): Edizione 1 (March 2018)

Volume 54 (2017): Edizione 4 (December 2017)
Special Edizione: This issue is dedicated to the memory of Milan Ryboš, DVM, D.Sc.

Volume 54 (2017): Edizione 3 (September 2017)

Volume 54 (2017): Edizione 2 (June 2017)

Volume 54 (2017): Edizione 1 (March 2017)

Volume 53 (2016): Edizione 4 (December 2016)

Volume 53 (2016): Edizione 3 (September 2016)

Volume 53 (2016): Edizione 2 (June 2016)

Volume 53 (2016): Edizione 1 (March 2016)

Volume 52 (2015): Edizione 4 (December 2015)

Volume 52 (2015): Edizione 3 (September 2015)

Volume 52 (2015): Edizione 2 (June 2015)

Volume 52 (2015): Edizione 1 (March 2015)

Volume 51 (2014): Edizione 4 (December 2014)

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Volume 51 (2014): Edizione 1 (March 2014)

Volume 50 (2013): Edizione 4 (December 2013)

Volume 50 (2013): Edizione 3 (September 2013)

Volume 50 (2013): Edizione 2 (June 2013)

Volume 50 (2013): Edizione 1 (May 2013)

Volume 49 (2012): Edizione 4 (December 2012)

Volume 49 (2012): Edizione 3 (September 2012)

Volume 49 (2012): Edizione 2 (June 2012)

Volume 49 (2012): Edizione 1 (March 2012)

Volume 48 (2011): Edizione 4 (December 2011)

Volume 48 (2011): Edizione 3 (September 2011)

Volume 48 (2011): Edizione 2 (June 2011)

Volume 48 (2011): Edizione 1 (March 2011)

Volume 47 (2010): Edizione 4 (December 2010)

Volume 47 (2010): Edizione 3 (September 2010)

Volume 47 (2010): Edizione 2 (June 2010)

Volume 47 (2010): Edizione 1 (March 2010)

Volume 46 (2009): Edizione 4 (December 2009)

Volume 46 (2009): Edizione 3 (September 2009)

Volume 46 (2009): Edizione 2 (June 2009)

Volume 46 (2009): Edizione 1 (March 2009)

Volume 45 (2008): Edizione 4 (December 2008)

Volume 45 (2008): Edizione 3 (September 2008)

Volume 45 (2008): Edizione 2 (June 2008)

Volume 45 (2008): Edizione 1 (March 2008)

Volume 44 (2007): Edizione 4 (December 2007)

Volume 44 (2007): Edizione 3 (September 2007)

Volume 44 (2007): Edizione 2 (June 2007)

Volume 44 (2007): Edizione 1 (March 2007)

Volume 43 (2006): Edizione 4 (December 2006)

Volume 43 (2006): Edizione 3 (June 2006)

Volume 43 (2006): Edizione 2 (June 2006)

Volume 43 (2006): Edizione 1 (March 2006)

Dettagli della rivista
Formato
Rivista
eISSN
1336-9083
ISSN
0440-6605
Pubblicato per la prima volta
22 Apr 2006
Periodo di pubblicazione
4 volte all'anno
Lingue
Inglese

Cerca

Volume 44 (2007): Edizione 3 (September 2007)

Dettagli della rivista
Formato
Rivista
eISSN
1336-9083
ISSN
0440-6605
Pubblicato per la prima volta
22 Apr 2006
Periodo di pubblicazione
4 volte all'anno
Lingue
Inglese

Cerca

11 Articoli
access type Accesso libero

Life cycle of the nematode Contracaecum rudolphii Hartwig, 1964 (sensu lato) from northern Poland under laboratory conditions

Pubblicato online: 01 Sep 2007
Pagine: 95 - 102

Astratto

Abstract

The study was aimed at following, under laboratory conditions, embryogenesis of the nematode Contracaecum rudolphii, and at identifying its intermediate hosts in northeastern Poland. Nematode eggs, isolated from the terminal part of the female uterus, were placed in 0.9 and 3% NaCl solutions, 1% formalin, and in tap water. Each solution batch was divided into 3 parts kept at 4, 15, and 23°C. Regardless of the temperature they were exposed to, the eggs placed in 1% formalin showed numerous deformations; as few as 5% of those eggs produced larvae. Embryogenesis was at its fastest in the eggs kept at 23°C. While still within the eggs, the larvae underwent two moults. The eggs hatched to produce the stage 3 larvae, which emerged surrounded by the cuticle of the preceding larval stage. Experimental infestations of zooplankton collected from Lake Kortowskie showed that only cyclopoid copepods could serve as the intermediate hosts. No differences in the infestation intensity were found between the guppies infested by the invasive larvae and those fed the infested cyclopoids.

Parole chiave

  • Contracaecum rudolphii
  • parasitic Nematoda
  • cormorant
  • embryogenesis
  • life cycle
access type Accesso libero

Spinitectus mariaisabelae n. sp. (Nematoda: Cystidicolidae) from the intestine of the freshwater fish Profundulus punctatus (Cyprinodontiformes) in Mexico

Pubblicato online: 01 Sep 2007
Pagine: 103 - 106

Astratto

Abstract

Spinitectus mariaisabelae n. sp. is described from the intestine of Profundulus punctatus (Günther) (Pisces, Cyprinodontiformes) from the Suchiapa River, State of Chiapas, Mexico. It is characterized largely by the bifurcate distal tip of the larger (left) spicule, spination of the cuticle separated into 4 longitudinal sectors, more or less regularly spaced rings of spines, and by the position of the excretory pore just posterior to the 7th ring of visible spines. By having the rings of spines divided into 4 sectors, the new species resembles 8 of the 15 American species; however, they can be easily distinguished by the number of spines in the first ring. S. mariaisabelae differs from all its American congeners by possessing a bifurcate distal tip of the left spicule, a unique feature among Spinitectus spp.

Parole chiave

  • Nematoda
  • Cystidicolidae
  • Spinitectus
  • Profundulus punctatus
  • freshwater fish
  • Chiapas
  • Mexico
access type Accesso libero

The helminth community of the Mediterranean mouse, Mus spretus, in a post-fire regenerated Mediterranean ecosystem

Pubblicato online: 01 Sep 2007
Pagine: 107 - 111

Astratto

Abstract

The helminth community of the Mediterranean mouse, Mus spretus, was analysed in a post-fire regenerated Mediterranean ecosystem. The study was carried out in the Spanish Natural Park of the Serra Calderona and comprised a 13 year period, from the 2nd to the 14th year after a wildfire. A total of 121 host individuals was analysed, 66 mice from the burned area and 55 from the non-burned area used as control. The results show a helminth community consisting of 10 helminth species, characterised by low diversity, with Syphacia obvelata as the only dominant helminth species. The helminth infracommunity, determined by its origin of capture, burned or non-burned areas, shows some significant differences. It is concluded that the helminth community of the Mediterranean mouse could be considered as a potential biological tag of the post-fire regeneration in Mediterranean ecosystems and therefore might explain some of the changes occurring and their repercussions in perturbed areas.

Parole chiave

  • helminth community
  • Mus spretus
  • post-fire
  • Mediterranean ecosystem
  • Serra Calderona
  • Spain
access type Accesso libero

Soil nematodes inhabiting an original dry meadow and an abandoned vineyard in the National Park Seewinkel, Eastern Austria

Pubblicato online: 01 Sep 2007
Pagine: 112 - 117

Astratto

Abstract

Nematode communities of cultivated vineyards showed characteristics typical for cultivated ecosystems, e.g. predominance of plant parasitic nematodes followed by bacterivores. The abandoned vineyard showed a reverse trophic structure: bacterivorous nematodes with short life cycles (cp 2) predominated and the population of plant parasites was small. The nematode trophic structure of the dry meadow was similar to the abandoned vineyard. Nevertheless, Principal Component Analysis (PCA) showed that differences in nematode communities were still detectable at the generic level, with some genera occurring solely in one or the other site (e.g. Xiphinema). Thus, soil nematodes indicated a recovery of primary production and decomposition processes in the formerly cultivated vineyard soil, because plant parasites consuming plant tissues decreased, and organic matter breakdown was slower, as in low-input grasslands. Communities of soil nematodes were also compared with intensively cultivated vineyards previously surveyed in Eastern Austria.

Parole chiave

  • diversity
  • grassland restoration
  • Nematoda
  • community indices
  • viticulture
access type Accesso libero

The first record of Dracunculus mulbus (Nematoda: Dracunculidae) in the Papuan olive python Apodora papuana (Ophidia: Boidae)

Pubblicato online: 01 Sep 2007
Pagine: 118 - 119

Astratto

Abstract

A male specimen of Dracunculus (Nematoda: Dracunculidae), collected in 1973 from the lung of the Papuan olive python Apodora papuana (Peters et Doria) and now deposited in the helminthological collection of the Natural History Museum in London, is identified as Dracunculus mulbus Jones et Mulder, 2007, a species recently described from the water python Liasis fuscus Peters in northern Australia. Apodora papuana is a new host record for D. mulbus and Papua New Guinea is apparently a new geographical record.

Parole chiave

  • parasitic nematode
  • Dracunculus
  • python
  • Apodora
  • Papua New Guinea
access type Accesso libero

Study of the 49 kDa excretory-secretory protein gene of Trichinella nativa and Trichinella spiralis

Pubblicato online: 01 Sep 2007
Pagine: 120 - 125

Astratto

Abstract

To study the function of the 49 kDa excretory-secretory (ES) protein gene (P49) of Trichinella, the genes was amplified by RT-PCR from RNA of Trichinella spiralis and Trichinella nativa and several Chinese Trichinella isolates of domestic animals, and sequenced after being cloned. The amplified products of these parasites produced bands of about 950 bp. The 97.2 % to 100 % nucleotides identity and 94.3 % to 100 % identity of deduced amino acids among P49 gene of these Trichinella strains showed the close relationship of these parasites. The P49 gene of T. nativa was cloned into the BamHI site of the prokaryotic expression vector pET-30a, and the recombinant vector was expressed. The expressed product was 40.8 kDa in size. In Western blot analysis, the expressed product was reactive to sera of mice infected with T. nativa, T. spiralis and their Chinese geographical strains.

Parole chiave

  • Trichinella nativa
  • Trichinella spiralis
  • 49kDa ES protein
  • gene sequence
  • western blot analysis
access type Accesso libero

The role of the colostrum and milk in Neospora caninum transmission

Pubblicato online: 01 Sep 2007
Pagine: 126 - 129

Astratto

Abstract

Neospora caninum, an apicomplexan protozoan causes economical losses due to reproductive failure associated with abortion among cattle. The transmission of N. caninum is possible through vertical transmission in utero, or according to the modern nomenclature endogenous and exogenous infection modes and horizontal transmission through ingestion of oocysts. Limited data is available on the vertical transmission during suckling time, via colostrum and milk.

In this paper the main scientific aim focused on N. caninum DNA detection in the milk and colostrum of seropositive cows have been reviewed. In this term, the risk of animals and humans infection has been discussed.

Parole chiave

  • Neospora caninum
  • vertical transmission
  • milk
  • colostrum
  • DNA
  • PCR
access type Accesso libero

Postembryonic development of tapeworms — source of novel phylogenetic characters for analysis of cestode evolution: comparative TEM studies

Pubblicato online: 01 Sep 2007
Pagine: 130 - 136

Astratto

Abstract

Ultrastructural features of juvenile cestodes (metacestodes) can provide useful characters for phylogenetic and evolutionary analyses. Until now, however, they have been relatively little utilised (Beveridge 2001, Chervy 2002). The postembryonic development and structure of fully formed metacestodes were examined in two cyclophyllideans: Taenia parva Baer, 1926 (Taeniidae); and Sobolevitaenia verulamii (Mettrick, 1958) Korniushin, 1972 (Dilepididae). In T. parva, three developmental stages were recognized: (1) an early stage of exogenous budding at the surface of the central vesicle; (2) a stage of polycephalic cyst development accompanied by segmentation of the growing metacestode strobila and an obvious decrease in the size of the central vesicle; (3) a fully formed metacestode of the strobilocercus type with 14–24 invaginated scoleces. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles and medullary parenchyma of larvae exhibit general similarity to the same structures in adults at both LM and TEM levels. The morphogenesis of the metacestode of T. parva is compared with that of polycephalic metacestodes of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually multiplying metacestodes (Mesocestoides vogae, hymenolepidids and dilepidids). In S. verulamii, the body of the cysticercoid with invaginated scolex armed with a double crown of rostellar hooks was completely surrounded by the cercomer, which appears to be separated from the cyst and scolex. The surface of the suckers is covered with a thick layer of glycocalyx. Five cell types were distinguished in the sections: (1) perikarya of metacestode tegument; (2) glycolgen-storing parenchymal cells; (3) glandular-type cells with large, electron-dense secretory-like granules; (4) flame cells; and (5) calcareous corpuscle-forming cells. The surface of the cercomer is covered by elongated microvilli, which evidently differ from characteristic microtriches covering all other parts of the metacestode surface. The ultrastructure of S. verulamii evidently differs from that of the other dilepidid cestode examined to date, Lateriporus geographicus, the cyst wall of which more resembles cysticercoids of Hymenolepididae than those of Dilepididae. Concluding remarks: Ultrastructural studies on metacestodes have considerable promise for providing important new characters for phylogenetic analysis. New TEM data on a great variety of cestode species are urgently needed. Until now, this field has not been exploited in a systematic fashion. Until more comprehensive studies become available, the current data are not yet amenable to analysis.

Parole chiave

  • cyclophyllidean cestodes
  • postembryonic development
  • comparative ultrastructure of metacestodes
  • cestode phylogeny and evolution
access type Accesso libero

Impact of praziquantel baiting on intestinal helminths of foxes in southwestern Germany

Pubblicato online: 01 Sep 2007
Pagine: 137 - 144

Astratto

Abstract

Fox baits containing 50 mg praziquantel were distributed by aircraft in a 3000 km2 area of southwestern Germany from 1995 to 1999. 20 baits / km2 were initially distributed at intervals of six to twelve weeks. Starting from a prebaiting prevalence of 64 % (95 % C.I. 59–69), a level of 15 % (C.I. 10–21) was reached after 18 months. Further decreasing the frequency and discontinuing the bait distribution caused a surge to 55 % (C.I. 49–61) within 36 months. Other cestode species (Taenia spp., Mesocestoides spp.) showed similar responses, while the prevalence of ascarid nematodes did not decline during baiting. New infections of fox cubs with E. multilocularis, but not with other cestodes, drastically decreased after one year. Prevalences of fox helminths in an external control area remained stable. Our data suggest that repeated praziquantel treatment of free ranging foxes is suitable to reduce the prevalence of E. multilocularis in a large area.

Parole chiave

  • Echinococcus multilocularis
  • alveolar echinococcosis
  • epidemiology
  • control
  • praziquantel
  • bait
access type Accesso libero

From cestodes to nematodes: 15 years of scientific collaboration between the Parasitological Institute SAS and the Section of Parasitology of the Sapienza University of Rome

Pubblicato online: 01 Sep 2007
Pagine: 145 - 149

Astratto

Abstract

The Parasitological Institute of the Slovak Academy of Sciences and the Section of Parasitology (formerly Institute of Parasitology) of the Department of Public Health Sciences of the Sapienza University of Rome have had a long term collaboration within several projects, starting with the first visiting fellowships in 1992 in Rome. Since then, the collaboration between the two institutions has continuously developed and has been focused mainly on the systematics of cestodes, starting in particular with the studies on the genetic polymorphism of fish Proteocephalus tapeworms in different host populations examined by enzyme electrophoresis. Some molecular studies have been later carried out on Eubothrium spp. and Echinococcus multilocularis, and most of our joint interest has been focused on Echinococcus granulosus and more recently, on Ascaris nematodes. The major achievements obtained during these years of collaboration are herein reported.

access type Accesso libero

Moravec, F.: Dracunculoid and anguillicoloid nematodes parasitic in vertebrates

Pubblicato online: 01 Sep 2007
Pagine: 150 - 150

Astratto

11 Articoli
access type Accesso libero

Life cycle of the nematode Contracaecum rudolphii Hartwig, 1964 (sensu lato) from northern Poland under laboratory conditions

Pubblicato online: 01 Sep 2007
Pagine: 95 - 102

Astratto

Abstract

The study was aimed at following, under laboratory conditions, embryogenesis of the nematode Contracaecum rudolphii, and at identifying its intermediate hosts in northeastern Poland. Nematode eggs, isolated from the terminal part of the female uterus, were placed in 0.9 and 3% NaCl solutions, 1% formalin, and in tap water. Each solution batch was divided into 3 parts kept at 4, 15, and 23°C. Regardless of the temperature they were exposed to, the eggs placed in 1% formalin showed numerous deformations; as few as 5% of those eggs produced larvae. Embryogenesis was at its fastest in the eggs kept at 23°C. While still within the eggs, the larvae underwent two moults. The eggs hatched to produce the stage 3 larvae, which emerged surrounded by the cuticle of the preceding larval stage. Experimental infestations of zooplankton collected from Lake Kortowskie showed that only cyclopoid copepods could serve as the intermediate hosts. No differences in the infestation intensity were found between the guppies infested by the invasive larvae and those fed the infested cyclopoids.

Parole chiave

  • Contracaecum rudolphii
  • parasitic Nematoda
  • cormorant
  • embryogenesis
  • life cycle
access type Accesso libero

Spinitectus mariaisabelae n. sp. (Nematoda: Cystidicolidae) from the intestine of the freshwater fish Profundulus punctatus (Cyprinodontiformes) in Mexico

Pubblicato online: 01 Sep 2007
Pagine: 103 - 106

Astratto

Abstract

Spinitectus mariaisabelae n. sp. is described from the intestine of Profundulus punctatus (Günther) (Pisces, Cyprinodontiformes) from the Suchiapa River, State of Chiapas, Mexico. It is characterized largely by the bifurcate distal tip of the larger (left) spicule, spination of the cuticle separated into 4 longitudinal sectors, more or less regularly spaced rings of spines, and by the position of the excretory pore just posterior to the 7th ring of visible spines. By having the rings of spines divided into 4 sectors, the new species resembles 8 of the 15 American species; however, they can be easily distinguished by the number of spines in the first ring. S. mariaisabelae differs from all its American congeners by possessing a bifurcate distal tip of the left spicule, a unique feature among Spinitectus spp.

Parole chiave

  • Nematoda
  • Cystidicolidae
  • Spinitectus
  • Profundulus punctatus
  • freshwater fish
  • Chiapas
  • Mexico
access type Accesso libero

The helminth community of the Mediterranean mouse, Mus spretus, in a post-fire regenerated Mediterranean ecosystem

Pubblicato online: 01 Sep 2007
Pagine: 107 - 111

Astratto

Abstract

The helminth community of the Mediterranean mouse, Mus spretus, was analysed in a post-fire regenerated Mediterranean ecosystem. The study was carried out in the Spanish Natural Park of the Serra Calderona and comprised a 13 year period, from the 2nd to the 14th year after a wildfire. A total of 121 host individuals was analysed, 66 mice from the burned area and 55 from the non-burned area used as control. The results show a helminth community consisting of 10 helminth species, characterised by low diversity, with Syphacia obvelata as the only dominant helminth species. The helminth infracommunity, determined by its origin of capture, burned or non-burned areas, shows some significant differences. It is concluded that the helminth community of the Mediterranean mouse could be considered as a potential biological tag of the post-fire regeneration in Mediterranean ecosystems and therefore might explain some of the changes occurring and their repercussions in perturbed areas.

Parole chiave

  • helminth community
  • Mus spretus
  • post-fire
  • Mediterranean ecosystem
  • Serra Calderona
  • Spain
access type Accesso libero

Soil nematodes inhabiting an original dry meadow and an abandoned vineyard in the National Park Seewinkel, Eastern Austria

Pubblicato online: 01 Sep 2007
Pagine: 112 - 117

Astratto

Abstract

Nematode communities of cultivated vineyards showed characteristics typical for cultivated ecosystems, e.g. predominance of plant parasitic nematodes followed by bacterivores. The abandoned vineyard showed a reverse trophic structure: bacterivorous nematodes with short life cycles (cp 2) predominated and the population of plant parasites was small. The nematode trophic structure of the dry meadow was similar to the abandoned vineyard. Nevertheless, Principal Component Analysis (PCA) showed that differences in nematode communities were still detectable at the generic level, with some genera occurring solely in one or the other site (e.g. Xiphinema). Thus, soil nematodes indicated a recovery of primary production and decomposition processes in the formerly cultivated vineyard soil, because plant parasites consuming plant tissues decreased, and organic matter breakdown was slower, as in low-input grasslands. Communities of soil nematodes were also compared with intensively cultivated vineyards previously surveyed in Eastern Austria.

Parole chiave

  • diversity
  • grassland restoration
  • Nematoda
  • community indices
  • viticulture
access type Accesso libero

The first record of Dracunculus mulbus (Nematoda: Dracunculidae) in the Papuan olive python Apodora papuana (Ophidia: Boidae)

Pubblicato online: 01 Sep 2007
Pagine: 118 - 119

Astratto

Abstract

A male specimen of Dracunculus (Nematoda: Dracunculidae), collected in 1973 from the lung of the Papuan olive python Apodora papuana (Peters et Doria) and now deposited in the helminthological collection of the Natural History Museum in London, is identified as Dracunculus mulbus Jones et Mulder, 2007, a species recently described from the water python Liasis fuscus Peters in northern Australia. Apodora papuana is a new host record for D. mulbus and Papua New Guinea is apparently a new geographical record.

Parole chiave

  • parasitic nematode
  • Dracunculus
  • python
  • Apodora
  • Papua New Guinea
access type Accesso libero

Study of the 49 kDa excretory-secretory protein gene of Trichinella nativa and Trichinella spiralis

Pubblicato online: 01 Sep 2007
Pagine: 120 - 125

Astratto

Abstract

To study the function of the 49 kDa excretory-secretory (ES) protein gene (P49) of Trichinella, the genes was amplified by RT-PCR from RNA of Trichinella spiralis and Trichinella nativa and several Chinese Trichinella isolates of domestic animals, and sequenced after being cloned. The amplified products of these parasites produced bands of about 950 bp. The 97.2 % to 100 % nucleotides identity and 94.3 % to 100 % identity of deduced amino acids among P49 gene of these Trichinella strains showed the close relationship of these parasites. The P49 gene of T. nativa was cloned into the BamHI site of the prokaryotic expression vector pET-30a, and the recombinant vector was expressed. The expressed product was 40.8 kDa in size. In Western blot analysis, the expressed product was reactive to sera of mice infected with T. nativa, T. spiralis and their Chinese geographical strains.

Parole chiave

  • Trichinella nativa
  • Trichinella spiralis
  • 49kDa ES protein
  • gene sequence
  • western blot analysis
access type Accesso libero

The role of the colostrum and milk in Neospora caninum transmission

Pubblicato online: 01 Sep 2007
Pagine: 126 - 129

Astratto

Abstract

Neospora caninum, an apicomplexan protozoan causes economical losses due to reproductive failure associated with abortion among cattle. The transmission of N. caninum is possible through vertical transmission in utero, or according to the modern nomenclature endogenous and exogenous infection modes and horizontal transmission through ingestion of oocysts. Limited data is available on the vertical transmission during suckling time, via colostrum and milk.

In this paper the main scientific aim focused on N. caninum DNA detection in the milk and colostrum of seropositive cows have been reviewed. In this term, the risk of animals and humans infection has been discussed.

Parole chiave

  • Neospora caninum
  • vertical transmission
  • milk
  • colostrum
  • DNA
  • PCR
access type Accesso libero

Postembryonic development of tapeworms — source of novel phylogenetic characters for analysis of cestode evolution: comparative TEM studies

Pubblicato online: 01 Sep 2007
Pagine: 130 - 136

Astratto

Abstract

Ultrastructural features of juvenile cestodes (metacestodes) can provide useful characters for phylogenetic and evolutionary analyses. Until now, however, they have been relatively little utilised (Beveridge 2001, Chervy 2002). The postembryonic development and structure of fully formed metacestodes were examined in two cyclophyllideans: Taenia parva Baer, 1926 (Taeniidae); and Sobolevitaenia verulamii (Mettrick, 1958) Korniushin, 1972 (Dilepididae). In T. parva, three developmental stages were recognized: (1) an early stage of exogenous budding at the surface of the central vesicle; (2) a stage of polycephalic cyst development accompanied by segmentation of the growing metacestode strobila and an obvious decrease in the size of the central vesicle; (3) a fully formed metacestode of the strobilocercus type with 14–24 invaginated scoleces. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles and medullary parenchyma of larvae exhibit general similarity to the same structures in adults at both LM and TEM levels. The morphogenesis of the metacestode of T. parva is compared with that of polycephalic metacestodes of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually multiplying metacestodes (Mesocestoides vogae, hymenolepidids and dilepidids). In S. verulamii, the body of the cysticercoid with invaginated scolex armed with a double crown of rostellar hooks was completely surrounded by the cercomer, which appears to be separated from the cyst and scolex. The surface of the suckers is covered with a thick layer of glycocalyx. Five cell types were distinguished in the sections: (1) perikarya of metacestode tegument; (2) glycolgen-storing parenchymal cells; (3) glandular-type cells with large, electron-dense secretory-like granules; (4) flame cells; and (5) calcareous corpuscle-forming cells. The surface of the cercomer is covered by elongated microvilli, which evidently differ from characteristic microtriches covering all other parts of the metacestode surface. The ultrastructure of S. verulamii evidently differs from that of the other dilepidid cestode examined to date, Lateriporus geographicus, the cyst wall of which more resembles cysticercoids of Hymenolepididae than those of Dilepididae. Concluding remarks: Ultrastructural studies on metacestodes have considerable promise for providing important new characters for phylogenetic analysis. New TEM data on a great variety of cestode species are urgently needed. Until now, this field has not been exploited in a systematic fashion. Until more comprehensive studies become available, the current data are not yet amenable to analysis.

Parole chiave

  • cyclophyllidean cestodes
  • postembryonic development
  • comparative ultrastructure of metacestodes
  • cestode phylogeny and evolution
access type Accesso libero

Impact of praziquantel baiting on intestinal helminths of foxes in southwestern Germany

Pubblicato online: 01 Sep 2007
Pagine: 137 - 144

Astratto

Abstract

Fox baits containing 50 mg praziquantel were distributed by aircraft in a 3000 km2 area of southwestern Germany from 1995 to 1999. 20 baits / km2 were initially distributed at intervals of six to twelve weeks. Starting from a prebaiting prevalence of 64 % (95 % C.I. 59–69), a level of 15 % (C.I. 10–21) was reached after 18 months. Further decreasing the frequency and discontinuing the bait distribution caused a surge to 55 % (C.I. 49–61) within 36 months. Other cestode species (Taenia spp., Mesocestoides spp.) showed similar responses, while the prevalence of ascarid nematodes did not decline during baiting. New infections of fox cubs with E. multilocularis, but not with other cestodes, drastically decreased after one year. Prevalences of fox helminths in an external control area remained stable. Our data suggest that repeated praziquantel treatment of free ranging foxes is suitable to reduce the prevalence of E. multilocularis in a large area.

Parole chiave

  • Echinococcus multilocularis
  • alveolar echinococcosis
  • epidemiology
  • control
  • praziquantel
  • bait
access type Accesso libero

From cestodes to nematodes: 15 years of scientific collaboration between the Parasitological Institute SAS and the Section of Parasitology of the Sapienza University of Rome

Pubblicato online: 01 Sep 2007
Pagine: 145 - 149

Astratto

Abstract

The Parasitological Institute of the Slovak Academy of Sciences and the Section of Parasitology (formerly Institute of Parasitology) of the Department of Public Health Sciences of the Sapienza University of Rome have had a long term collaboration within several projects, starting with the first visiting fellowships in 1992 in Rome. Since then, the collaboration between the two institutions has continuously developed and has been focused mainly on the systematics of cestodes, starting in particular with the studies on the genetic polymorphism of fish Proteocephalus tapeworms in different host populations examined by enzyme electrophoresis. Some molecular studies have been later carried out on Eubothrium spp. and Echinococcus multilocularis, and most of our joint interest has been focused on Echinococcus granulosus and more recently, on Ascaris nematodes. The major achievements obtained during these years of collaboration are herein reported.

access type Accesso libero

Moravec, F.: Dracunculoid and anguillicoloid nematodes parasitic in vertebrates

Pubblicato online: 01 Sep 2007
Pagine: 150 - 150

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