Gastrointestinal helminth parasites of the common wallaroo or euro, Osphranter robustus (Gould) (Marsupialia: Macropodidae) from Australia.

The gastrointestinal helminth parasites of 170 common wallaroos or euros, Osphranter robustus (Gould), collected from all mainland states in which the species occurs as well as the Northern Territory, are presented, including previously published data. A total of 65 species of helminths were encountered, including four species of anoplocephalid cestodes found in the bile ducts and small intestine, and 61 species of strongylid nematodes, all but two of which occurring in the stomach, and with the remainder occurring in the terminal ileum, caecum and colon. Among the mainland subspecies of O. robustus, 52 species of helminths were encountered in O. r. robustus, compared with 30 species in O. r. woodwardi and 35 species in O. r. erubescens. Of the parasite species encountered, only 17 were specific to O. robustus, the remaining being shared with sympatric host species. Host-specific species or species occurring in O. robustus at a high prevalence can be classified as follows: widely distributed; restricted to northern Australia; restricted to the northern wallaroo, O. r. woodwardi; found only in the euro, O. r. erubescens; found essentially along the eastern coast of Australia, primarily in O. r. robustus; and species with highly limited regional distributions. The data currently available suggest that the acquisition of a significant number of parasites is due to co-grazing with other macropodids, while subspeciation in wallaroos as well as climatic variables may have influenced the diversification of the parasite fauna.

Pterobothrium sp. parasitando linguado, Xystreurys rasile (Jordan, 1891), coletados no litoral do Estado do Rio de Janeiro, Brasil e sua importância na inspeção do pescado / Pterobothrium sp. parasitizing flounders, Xystreurys rasile (Jordan, 1891), collected off the coast the State of Rio de Janeiro, Brazil and its fishing inspection importance

Alguns parasitos, podem conferir aspecto repugnante ao pescado, sendo condenados pelo Serviço de Inspeção, quando na indústria de beneficiamento. Entre novembro de 2010 e maio de 2018 foram adquiridos 36 espécimes de Xystreurys rasile em mercados de pescados no município do Rio de Janeiro, Brasil. Os peixes foram identificados, medidos, pesados e necropsiados. Os cestoides foram processados segundo as técnicas usuais em helmintologia. Cinco linguados estavam parasitados por 29 cestoides do gênero Pterobothrium, os índices parasitários foram: prevalência (14%), intensidade média (5,8), abundância média (0,8) e amplitude de infecção (2-12) e os sítios de infecção foram estômago, intestino, rim, fígado, serosas do estômago, baço e fígado e cavidade abdominal. Este é o primeiro registro de Pterobothrium sp. parasitando X. rasile.

Tentacularia coryphaenae (Cestoda: Trypanorhyncha) em Fistularia petimba Lacépède, 1803 coletados Estado do Rio de Janeiro, Brasil e sua importância na inspeção do pescado / Tentacularia coryphaenae (Cestoda: Trypanorhyncha), Fistularia petimba Lacépède, 1803 collected off the coast of the State of Rio de Janeiro, Brazil and its importance in fish inspection

A presença de helmintos no pescado resulta em perdas econômicas devido a repugnância, além do risco de desenvolver reações alérgicas, reforçando a importância da inspeção higiênico-sanitária, como o caso dos cestoides da ordem Trypanorhyncha. Entre janeiro e setembro de 2018 foram adquiridos 30 espécimes de Fistularia petimba no Estado do Rio de Janeiro. Após a necropsia no Laboratório de Inspeção e Tecnologia de Pescado da Faculdade de Veterinária-UFF, foi verificado a positividade de dois peixes para o cestoide identificado como sendo da espécie Tentacularia coryphaenae, presente na cavidade abdominal e mesentério, apresentando os seguintes índices parasitários: prevalência 6,6%, intensidade média 1; abundância média 0,06.

An insect-tapeworm model as a proxy for anthelminthic effects in the mammalian host.

Invertebrate models provide several important advantages over their vertebrate counterparts including fewer legislative stipulations and faster, more cost-effective experimental procedures. Furthermore, various similarities between insect and mammalian systems have been highlighted. To obtain maximum use of invertebrate models in pharmacology, their fidelity as analogues of vertebrate systems requires verification. We utilised a flour beetle (Tenebrio molitor)-tapeworm (Hymenolepis diminuta) model to evaluate the efficacy of known anthelmintic compounds, praziquantel, mebendazole and levamisole against H. diminuta cysticercoid larvae in vitro. Inhibition of cysticercoid activity during the excystation procedure was used as a proxy for worm removal. The effects of the three compounds mirrored their relative efficacy in treatment against adult worms in mammalian systems; however, further study is required to determine the fidelity of this model in relation to dose administered. The model precludes comparison of consecutive daily administration of pharmaceuticals in mammals due to cysticercoids not surviving outside of the host for multiple days. Treatment of beetles in vivo, followed by excystation of cysticercoids postdissection could potentially allow for such comparisons. Further model validation will include analysis of pharmaceutical efficacy in varying H. diminuta isolates and pharmaceutical dilution in solvents other than water. Notwithstanding, our results demonstrate that this model holds promise as a method to efficiently identify promising new cestocidal candidates.

Checklist of helminths from lizards and amphisbaenians (Reptilia, Squamata) of south America: [review]

A comprehensive and up to date summary of the literature on the helminth parasites of lizards and amphisbaenians from South America is herein presented. One-hundred eighteen lizard species from twelve countries were reported in the literature harboring a total of 155 helminth species, being none acanthocephalans, 15 cestodes, 20 trematodes and 111 nematodes. Of these, one record was from Chile and French Guiana, three from Colombia, three from Uruguay, eight from Bolivia, nine from Surinam, 13 from Paraguay, 12 from Venezuela, 27 from Ecuador, 17 from Argentina, 39 from Peru and 103 from Brazil. The present list provides host, geographical distribution (with the respective biome, when possible), site of infection and references from the parasites. A systematic parasite-host list is also provided.

Trace element concentrations in Proteocephalus macrocephalus (Cestoda) and Anguillicola crassus (Nematoda) in comparison to their fish host, Anguilla anguilla in Ria de Aveiro, Portugal.

The use of some fish parasites as bioindicators of heavy metal pollution has been demonstrated as particularly adequate due to their capacity of bioconcentration. This study evaluated the effect of Proteocephalus macrocephalus on the accumulation of trace elements in the edible fish, Anguilla anguilla, in a contaminated area in Portugal (Ria de Aveiro). Also, the model P. macrocephalus/A. anguilla was assessed as a bioindicator system in the presence of the highly prevalent nematode Anguillicola crassus. Samples (kidney, liver, muscle, A. crassus and P. macrocephalus) of 20 eels harbouring A. crassus and another 20 harbouring both A. crassus and P. macrocephalus were selected for element analysis by ICP-MS. The highest concentrations of Cr, Ni and Zn were detected in P. macrocephalus. However, there was a higher liver and muscle Cr concentration in eels not infected by P. macrocephalus. Also, the nematode A. crassus presented higher Cr concentrations in those eels harbouring P. macrocephalus. Results suggest that P. macrocephalus individuals accumulate Cr and Ni while levels of Cr in eel livers and Ni levels in eel kidney are reduced. The system P. macrocephalus/A. anguilla yielded bioaccumulation factors for Cr, Ni, Pb and Zn, whereas bioaccumulation of Cu, Cr and Pb in A. crassus varied according to eel co-infection with P. macrocephalus, thus emphasising the possible role of cestode infection in metal metabolization/storage processes in host tissues. Results suggest that heavy metal pollution in Ria de Aveiro has been decreasing although it is still higher than in other contaminated areas in Europe. Nevertheless, eel consumption in Ria de Aveiro represents no risk for humans although they may represent a real contamination risk for wildlife. The system P. macrocephalus/A. anguilla is proposed as another promising bioindicator system to evaluate environmental Cr, Ni, Pb and Zn exposure in estuarine areas where both species co-occur.

Biomagnification and polychlorinated biphenyl congener distribution in an aquatic predator-prey, host-parasite system.

Biomagnification and polychlorinated biphenyl (PCB) congener distribution was examined in a predator-prey, host-parasite system, in which Atlantic salmon (Salmo salar) preyed upon sprat (Sprattus sprattus). Eubothrium crassum was an intestinal parasite in salmon that also "preyed upon" sprat, because the parasites gained access to foodstuffs via the host (salmon) gut. Salmon contained significantly higher concentrations of total PCBs compared to both parasites and prey (sprat), but no difference in PCB concentration was found between sprat and E. crassum. Salmon biomagnified several PCB congeners from their diet (sprat), whereas parasites did not, despite the fact that both salmon and their parasites ingested the same prey. Differences in nutrient uptake mechanisms between the host and their parasites, in addition to the lack of a gastrointestinal tract in the cestode, may explain the lack of biomagnification in E. crassum. No difference was found in PCB congener distribution between parasites, salmon, and sprat, and none of the animal types showed a preference for accumulating more or less lipophilic congeners (congeners with a high or low octanol/water partition coefficient [K(ow)]). Biomagnification factors for individual congeners in salmon did not increase with K(ow); rather, they were constant, as shown by a linear relationship for congener concentration in prey and predator.

Insight into the role of cetaceans in the life cycle of the tetraphyllideans (Platyhelminthes: Cestoda).

Four types of tetraphyllidean larvae infect cetaceans worldwide: two plerocercoids differing in size, 'small' (SP) and 'large' (LP), and two merocercoids referred to as Phyllobothrium delphini and Monorygma grimaldii. The latter merocercoid larvae parasitize marine mammals exclusively and exhibit a specialised cystic structure. Adult stages are unknown for any of the larvae and thus the role of cetaceans in the life cycle of these species has been a long-standing problem. The SP and LP forms are thought to be earlier stages of P. delphini and M. grimaldii that are presumed to infect large pelagic sharks that feed on cetaceans. A molecular analysis of the D2 variable region of the large subunit ribosomal DNA gene based on several individuals of each larval type collected from three Mediterranean species of cetaceans showed consistent and unique molecular signatures for each type regardless of host species or site of infection. The degree of divergence suggested that LP, P. delphini and M. grimaldii larvae may represent separate species, whereas SP may be conspecific with M. grimaldii. In all host species, individuals of SP accumulated in the gut areas in which the lymphoid tissue was especially developed. We suggest therefore that these larvae use the lymphatic system to migrate to the abdominal peritoneum and mesenteries where they develop into forms recognizable as M. grimaldii. The plerocercoid stage of P. delphini remains unknown. In a partial phylogenetic tree of the Tetraphyllidea, all larvae formed a clade that included a representative of the genus Clistobothrium, some species of which parasitize sharks such as the great white which is known to feed on cetaceans. A bibliographic examination of tetraphyllidean infections in marine mammals indicated that these larvae are acquired mostly offshore. In summary, the evidence suggests that cetaceans play a significant role in the life cycle of these larvae. In addition, it seems clear that cetaceans act as natural intermediate hosts for P. delphini and M. grimaldii, as within these hosts they undergo development from the plerocercoid stage to the merocercoid stage. Because tetraphyllidean species use fish, cephalopods and other marine invertebrates as intermediate hosts, the inclusion of cetaceans in the life cycle would have facilitated their transmission to apex predators such as the large, lamnid sharks. The biological significance of infections of LP in cetaceans is unclear, but infections do not seem to be accidental as such larvae show high prevalence and abundance as well as a high degree of site specificity, particularly in the anal crypts and bile ducts.

Difilobotríase: relato de caso no município de Ribeirão Preto, SP, Brasil / Diphyllobothriasis: a case report of a human infection in Ribeirão Preto, SP, Brazil

A difilobotríase é uma parasitose intestinal causada pela tênia do peixe, associada à ingestão de peixe cru ou mal-cozido. Este relato descreve o primeiro caso de difilobotríase autóctone em um estudante de 22 anos do município de Ribeirão Preto, SãoPaulo, Brasil. O diagnóstico foi realizado pela clarificação das proglótides e pelo encontro de ovos operculados no exame microscópico das fezes do paciente. A investigação epidemiológica demonstrou que a fonte de infecção neste caso esteve relacionada à ingestão de sashimi de salmão cru

Nematóides da família Anisakidae e cestóides da ordem Trypanorhyncha em peixes teleósteos comercializados no estado do Rio de Janeiro / Nematodes of Anisakidae family and cestodes of Trypanorhyncha order in teleosts fishes commercialized in Rio de Janeiro State

O objetivo deste estudo foi realizar a pesquisa de formas larvares de nematóides da família Anisakidae e cestóides da ordemTrypanorhyncha em peixes teleósteos de grande comercialização no estado do Rio de Janeiro. Foram necropsiados 79espécimes que tiveram a sua cavidade geral e musculatura analisadas quanto à presença de parasitos. Do total de exemplaresde peixes, aproximadamente 20 por cento apresentaram pelo menos uma das espécies de parasitos pesquisados. As espécies depeixes mais acometidos por cestóides da ordem Trypanorhyncha foram Lophius gastrophisus (6) e Netuma barba (6), amboscom valores de 66,7 por cento. Os maiores percentuais de exemplares positivos para nematóides da família Anisakidae foram de 60,0 por cento para Genypterus brasiliensis (5); 47,6 por cento para Pagrus pagrus (21), e 42,9 por cento para Pseudopercis numida (7). As espéciesMicropogonias furnieri e Pagrus pagrus apresentaram ambos os parasitismos.

The purpose of this study was to evaluate the presence of nematodes larvaes of Anisakidae family and cestodes larvaes ofTrypanorhyncha order, in teleosts fishes commercialized in Rio de Janeiro state. Were necropsied 79 specimens and analyzedfor the presence of parasites. Of the total of units, about 20 percent had at least one species of parasite. The most infested species bycestodes of the order Trypanorhyncha was Lophius gastrophisus (6) and Netuma barba (6), both of them with values of 66,7 percent.However the high percentiles of positive units for nematodes of the Anisakidae family were 60,0 percent for Genypterus brasiliensis(5); 47.6 percent for Pagrus pagrus (21), and 42.9 percent for Pseudopercis numida (7). The species Micropogonias furnieri and Pagruspagrus had presented both the parasitisms.

Hydatid control in Australia: where it began, what we have achieved and where to from here.

Echinococcus granulosus was imported into Australia with domestic livestock about 200 years ago. It spread rapidly through domestic animals and quickly became a public health problem in the new colony. Control was hampered by ignorance of the transmission pattern. The association between metacestodes and tapeworms was not elucidated until 63 years after the arrival of the First Fleet. Australian wildlife were highly susceptible to infection with E. granulosus and wildlife/domestic animal interaction facilated rapid infiltration of wildlife by E. granulosus. The wildlife reservoir has hampered hydatid control campaigns on mainland Australia but successful eradication has been achieved in the island state of Tasmania where there was no wildlife reservoir. The application of a new recombinant vaccine for sheep in control campaigns and the use of praziquantel baits for controlling infection in dingoes around bush campsites and picnic areas is discussed.

Cestodes of cestodes of Peruvian freshwater stingrays.

Adult tetraphyllidean tapeworms (Platyhelminthes: Eucestoda) from the spiral intestines of 3 species of potamotrygonid stingrays (Paratrygon aiereba, Potamotrygon castexi, and Portamotrygon motoro) in the Madre de Dios river in Peru were found to host numerous cysts embedded in their parenchymal tissues. Histological sections of the cysts revealed the presence of a scolex bearing 4 suckers and an unarmed apical organ consistent with larval stages of both Cyclophyllidea and Proteocephalidea. To further elucidate their identities, partial 28S ribosomal DNA (rDNA) sequences were characterized from 3 cysts and 4 adult Rhinebothrium spp. 'host' worms and screened against all available cestode 28S rDNA data. Initial BLAST screening and subsequent alignment ruled out the possibility that the cysts were cyclophyllidean, and the cyst and adult sequences were thus aligned together with all available lecanicephalidean, litobothriidean, proteocephalidean, and tetraphyllidean sequences. Sequences from all 3 cysts were identical, and phylogenetic analysis clearly placed them among derived members of the Proteocephalidea, although no exact match was found. Sequences from the adult host worms formed 2 identical pairs and grouped together with other tetraphyllidean species from rays. These results are compared with records of hyperparasites of South American catfish cestodes. This is the first confirmed record of a proteocephalidean cestode parasitizing a tetraphyllidean cestode.

Helminth growth in vertebrate hosts: does host sex matter?

Helminth infections are usually more severe in male than in female vertebrate hosts. If parasite establishment is easier in male hosts, parasite growth may also be facilitated in males. This was tested with a meta-analysis of published between growth rates of worms in male and female vertebrate hosts. Two-thirds of the 48 comparisons found showed higher growth in male hosts than in females, but the average relative difference did not differ from zero. However, after controlling for sample size and for the variability in the original data, a small but significant effect of host sex was found. The meta-analysis suggests that male hosts harbour not only more helminths than females, but also slightly larger ones.

Ultrastructure of spermiogenesis and the mature spermatozoon of Tetrabothrius erostris Loennberg, 1896 (Cestoda, Tetrabothriidae).

The spermiogenesis of Tetrabothrius erostris is characterized by the following events: formation of a differentiation zone containing 2 basal bodies and a pair of rootlets; one of the basal bodies gives rise to a free flagellum, the other induces formation of a flagellar bud; rotation at 90 degrees of the flagellum prior to its fusion with the middle cytoplasmic process of the differentiation zone and partial rotation of the flagellar bud; penetration of the nucleus between the rootlets and appearance of a spur-like protrusion in the differentiation zone; elongation and twisting of the differentiation zone, resulting in twisting of the peripheral microtubules and migration of the nucleus; formation of a crested body; proximal densification of the spermatozoon prior to its detachment from the spermatid rosette. The mature spermatozoon has a single axoneme of 9+"1" type and twisted peripheral microtubules. It consists of 3 portions: a proximal part with a crested body, a middle region rich in beta-glycogen, and a distal part containing the nucleus. The pattern of spermiogenesis resembles most closely that in phyllobothriid tetraphyllideans, and probably reflects a relationship of the family Tetrabothriidae with this group.

Parasitos de Balistes vetula (L) e sua importância na inspeção do pescado / Parasites of Balistes vetula (L) and their importance in fish inspection

Foram examinados 50 peixes da espécie Balistes vetula L., pescados no litoral do Estado do Rio de Janeiro, com o objetivo de se detectar larvas de cestóides da ordem Trypanorhyncha e larvas de nematóides anisakídeos. Os peixes apresentavam comprimentos entre 17 e 28 em, sendo que aqueles com médias compreendidas entre 24 e 28 em achavam-se mais infectados. Do total de espécimens necropsiados, 88% achavam-se parasitados por cestóides Trypanorhyncha das espécies Callitetrarhynchus gracilis, Callitetrarhynchus speciosus e pelo gênero Otobothrium e 56% achavam-se parasita-dos por larvas de anisakideos do gênero Contracaecum.

Fifty specimens of lhe species Balistes vetula (L.) captured along lhe coast of Rio de Janeiro State were examined to detect cestode larvae belonging to lhe order Trypanorhyncha and nematodes anisakids larvae. The fishes measured from 17 to 28 cm. 88% of them were parasited by Trypanorhyncha cestode of the species Callitetrarhynchus gracilis, Callitetrarhynchus speciosus and by the genus Otobothrium. 56% were parasited by anisakids larvae of the genus Contracaecum. Specimens between 24 and 28 em were found more parasited.

Description of the new species acanthobothrium satyanarayanaraoi from rhinobatus granulatus from Waltair coast, India

Se describe la nueva especie de cestode parásito acanthobothrium satyanarayanaraoi del huésped elasmobranquio rhinobatus granulatus. Este gusano se diferencia de otras especies conocidas del género acanthobothrium en su mayor tamaño, escólex más grande, botridias y en algunas otras características

Nota sobre algunos helmintos para el Perú / Note about some helmintes for Peru

Se da conocer por primera vez en el Perú, la presencia de algunos helmintos. Cestoda: Ophiotaenia calmetti (Barros, 1858) La Rue, 1911. Trematoda: Athesmia heterolecithoides (Braun, 1899) Looss, 1899; Nematoda: Molineus nasuae Lent & Freitas, 1938; Uncinaria stenocephala (Railliet, 1884) Railliet, 1885; Uncinaria sp. y Hastospiculum onchocercum Chiwood, 1932

Laboratory diagnosis of worms and miscellaneous specimens.

This article outlines the procedures to be followed when a macroscopic object thought to be a worm or other type of parasite is submitted to the clinical laboratory. These are often collected and submitted by the patient, but also may be submitted by the attending physician, the surgeon, or the pathologist. Examples of the various parasites and parasite-like objects that have been submitted to clinical laboratories are listed. Methods for preserving and examining such objects, using materials and reagents available in the clinical laboratory, are presented.