Parasitosis in Pet Dogs from Rondônia, Amazon Biome, and Human Perception of Zoonoses.

Zoonotic parasitic diseases in dogs are particularly concerning in regions with low human development indices due to inadequate sanitary services and insufficient environmental and health education. This study aimed to assess the parasitological status of dogs living in households and evaluate their owners' knowledge about zoonoses. A total of 183 dogs from Rolim de Moura, Rondônia State, were screened for the presence of ectoparasites, and 163 fecal samples were collected for analysis. The results showed that 74.23% (112/163) of the animals had at least one species of endoparasite. The most identified pathogens were Ancylostoma spp. (68.71%, 112/163), Trichuris vulpis (11.66%, 19/163), Toxocara canis (6.75%, 11/163), Cystoisospora canis (4.91%, 8/163), Dipylidium caninum (1.23%, 2/163), and Hammondia/Neospora (0.61%, 1/163). Ectoparasites were observed in 43.17% (79/183) of the evaluated animals, with Rhipicephalus sanguineus found in 31.15% (57/183) and Ctenocephalides felis felis in 20.77% (38/183). Only 11.48% (7/61) of the owners were familiar with the term "Zoonoses." However, a significant majority (83.61%, 51/61) believed that dogs can transmit diseases to humans. Our findings highlight the prevalence of parasites in the studied area and associated risk factors, underscoring the urgent need for educational interventions to raise awareness about these diseases and their risks to human health.

Gastrointestinal parasites of Peltocephalus dumerilianus (Testudines: Podocnemididae) from Jaú National Park, Brazilian Amazon.

The big-headed Amazon River turtle, Peltocephalus dumerilianus, is endemic to the Orinoco and Amazon River basins. It is a food source for local communities, often unsustainably. Knowledge about P. dumerilianus' parasitological fauna and host-parasite relationships is limited. Thus, ecological aspects of gastrointestinal parasitism in this species were investigated. Helminths were found in the gastrointestinal tract of 21 turtles, morphologically identified, and infection descriptors calculated. All animals harbored helminths: nematodes Ancyracanthus pinnatifidus, Paratractis hystrix, Atractis trematophila, Klossinemella conciliatus indeterminate three Klossinemella species, and digeneans Nematophila grandis, Helicotrema spirale, and Telorchis hagmanni. The highest parasite load occurred in the large intestine, followed by the small intestine and stomach. Shell length directly correlated with parasite burden of heteroxenic helminths, with males having higher burden than females. This is the first record of A. trematophila, K. conciliatus, and T. hagmanni in P. dumerilianus, and new location record for A. trematophila, P. hystrix, N. grandis, H. spirale, and T. hagmanni. Three potentially new Klossinemella species are presented.

Endoparasites of marsupials in fragments of the Atlantic rainforest, western Paraná State, Brazil.

Knowledge of taxonomy and biodiversity of parasites is fundamental to better understand ecosystem dynamics. The objective of this study was to describe the helminth fauna of two species of marsupials in five fragments of the Atlantic rainforest in the western region of Paraná State, Brazil. In a total of 4050 trap-nights, the animals were captured using Sherman, Tomahawk, and Pitfall traps, euthanized, necropsied, and their organs inspected for helminths. After identification of the parasites, descriptors of infection, such as prevalence, mean abundance, mean intensity, and range of intensity, were calculated. Collectively, six helminth species were observed in 18 animals. The following five species were observed in Marmosa paraguayana: Viannaia hamata (58.8%), Gracilioxyuris agilisis (52.9%), Travassostrongylus sextus (17.6%), Oncicola luehei (5.9%), and Pritchardia boliviensis (5.9%). Whereas the following two species were observed in Monodelphis dimidiata: Trichohelix tuberculata (100%) and Travassostrongylus sextus (100%). This study represents a new locality record for all helminths described herein, and a new host for four helminth species. This is the first report on the helminth fauna of Monodelphis dimidiata, expanding knowledge about marsupials in the Brazilian Atlantic Forest.

Helminths of South American fur seals (Arctocephalus australis) from the Subtropical Convergence Zone of the Southwestern Atlantic.

Parasites are important components of ecosystems and may contribute to the ecological aspects of their hosts and indicate the integrity of their environment. To identify the gastrointestinal helminths of the South American fur seal, Arctocephalus australis, 52 animals found dead on the Rio Grande do Sul coast, Southern Brazil, were necropsied. All studied animals were parasitized, and 104,670 specimens of helminths from three phyla and 14 taxa were collected. Adult specimens represented five of the identified species: Contracaecum ogmorhini, Adenocephalus pacificus, Stephanoprora uruguayense, Ascocotyle (Phagicola) longa, and Corynosoma australe; and one of the identified genera: Strongyloides sp. Immature forms represented the other eight taxa: Anisakidae gen. sp., Anisakis sp., Pseudoterranova sp., Contracaecum sp., Tetrabothriidae gen. sp., Cestoda gen. sp., Corynosoma cetaceum, and Bolbosoma turbinella. The acanthocephalan C. australe was the most prevalent and abundant parasite, whereas Strongyloides sp. had the highest intensity. This is the first record of the nematode Anisakis sp., digenean S. uruguayense, and acanthocephalan B. turbinella in this host. Trophic generalist species such as A. australis can be good indicators of the composition of the helminth fauna of their ecosystems, indicating the presence of zoonotic parasites transmitted by the consumption of fish.

Epidemiology and Integrative Taxonomy of Helminths of Invasive Wild Boars, Brazil.

Wild boars (Sus scrofa) are a significant invasive species in Brazil. We evaluated the helminth diversity of 96 wild boars in São Paulo state. Helminth infection descriptors were calculated, the species were identified and their 18S, 28S rDNA and internal transcribed spacer (ITS) regions were amplified for phylogenetic analyses. Ascarops strongylina, Strongyloides ransomi, Globocephalus urosubulatus, Oesophagostomum dentatum, Trichuris suis, Metastrongylus salmi, Metastrongylus pudendotecus, Ascaris suum and Stephanurus dentatus and Macracanthorhynchus hirudinaceus were identified. Globocephalus urosubulatus had the highest prevalence and mean abundance, and most animals had mixed infections with three parasite species. There was no association between parasite intensity and prevalence and host sex and body condition index (p > 0.05). Novel DNA sequences were obtained from G. urosubulatus, A. strongylina, and S. dentatus. This is the first study on the helmint diversity of non-captive wild boars in Brazil, and the first report of the occurrence of M. hirudinaceus, G. urosubulatus and S. dentatus in Brazilian wild boars. Non-captive wild boars of São Paulo State did not act as capture hosts for native helminth species but maintained their typical parasites, common to domestic pigs. They may act as parasite dispersers for low-tech subsistence pig farming and for native Tayassuidae.

Endoparasites of marsupials in fragments of the Atlantic rainforest, western Paraná State, Brazil / Endoparasitas de marsupiais em fragmentos de Mata Atlântica no oeste do Estado do Paraná, Brasil

Abstract Knowledge of taxonomy and biodiversity of parasites is fundamental to better understand ecosystem dynamics. The objective of this study was to describe the helminth fauna of two species of marsupials in five fragments of the Atlantic rainforest in the western region of Paraná State, Brazil. In a total of 4050 trap-nights, the animals were captured using Sherman, Tomahawk, and Pitfall traps, euthanized, necropsied, and their organs inspected for helminths. After identification of the parasites, descriptors of infection, such as prevalence, mean abundance, mean intensity, and range of intensity, were calculated. Collectively, six helminth species were observed in 18 animals. The following five species were observed in Marmosa paraguayana: Viannaia hamata (58.8%), Gracilioxyuris agilisis (52.9%), Travassostrongylus sextus (17.6%), Oncicola luehei (5.9%), and Pritchardia boliviensis (5.9%). Whereas the following two species were observed in Monodelphis dimidiata: Trichohelix tuberculata (100%) and Travassostrongylus sextus (100%). This study represents a new locality record for all helminths described herein, and a new host for four helminth species. This is the first report on the helminth fauna of Monodelphis dimidiata, expanding knowledge about marsupials in the Brazilian Atlantic Forest.

Resumo Conhecimentos taxonômicos e da biodiversidade parasitária são fundamentais para uma melhor compreensão da dinâmica do ecossistema. O objetivo do estudo foi descrever a helmintofauna de marsupiais em cinco fragmentos de Mata Atlântica, na região Oeste do Estado do Paraná, Brasil. Em um total de 4.050 armadilhas/noite, os animais foram capturados com as do tipo Sherman, Tomahawk e Pitfall, eutanasiados, necropsiados e seus órgãos inspecionados em busca de helmintos. Após a identificação do parasita, foram calculados os indicadores de infecção (prevalência, abundância média, intensidade média e variação de intensidade). Seis espécies de helmintos foram observadas em dezoito animais; cinco em Marmosa paraguayana: Viannaia hamata (58,8%), Gracilioxyuris agilisis (52,9%), Travassostrongylus sextus (17,6%), Oncicola luehei (5,9%) e Pritchardia boliviensis (5,9%), e duas em Monodelphis dimidiata: Trichohelix tuberculata (100%) e Travassostrongylus sextus (100%). Este estudo representa um novo registro de localidade para todos os helmintos descritos e um novo hospedeiro para quatro deles. Trata-se do primeiro relato da helmintofauna de Monodelphis dimidiata, expandindo-se os conhecimentos sobre marsupiais na mata Atlântica brasileira.

Rodent helminths in fragmented Atlantic Forest areas in the western region of the state of Paraná.

Rodents are small mammals that can be parasitized by various helminths. This study aimed to identify and describe the ecological indicators of infection in rodents captured in fragments of the Atlantic Forest in the western region of Paraná State, Brazil. Sixty-eight specimens of five rodent species were collected, necropsied, and inspected in search of helminths. The parasites were stored in 70% ethanol, morphologically identified, and counted for calculation of infection indicators. Fourteen species of helminths and one species of Crustacea were recorded: ten in Akodon montensis, four in Mus musculus, two in Thaptomys nigrita, two in Oligoryzomys nigripes, and one in Euryoryzomys russatus. The registered species of parasites were: Rodentolepis akodontis, Angiostrongylus sp., Protospirura numidica criceticola, Trichuris navonae, Syphacia alata, Syphacia criceti, Syphacia evaginata, Trichofreitasia lenti, Stilestrongylus aculeata, Stilestrongylus eta, Stilestrongylus gracielae, Stilestrongylus franciscanus, Stilestrongylus moreli, Stilestrongylus sp., and Pentastomida gen. sp. A positive correlation between the intensity of infection of T. navonae and T. lenti was observed with the body condition index of the host A. montensis. For all species, this study represents a new register of locality, and for eight of them a new host.

Parasitological status of vicuñas (Vicugna vicugna) from southeastern Peru and its relationship with fiber quality.

We aim to describe the parasitic population in vicuñas from three Andean communities and its relationship with fiber quality using 115 fecal and 22 fiber samples, classified according to sex, age, body condition score, and management system. Coproparasitologic diagnostic revealed that 84.4% of animals presented at least one type of parasite egg/oocyst. Most frequent parasite egg/oocyst were Strongyle-type eggs (54.8%) and Eimeria punoensis (38.3%). Wild vicuñas had a higher prevalence of Strongyle-type eggs (91.4%) than semi-captive (38.8%) animals, and age was significative to Eimeria infection; crias had the highest frequency (100%) when compared to yearlings (84.2%) and adults (49.4%). Larvae identification revealed a strong influence of domestic animals on vicuña parasite community, presenting the first report of Bunostomum phlebotomum and Gaigeria pachyscelis in vicuñas from southeastern Peru. Females had a significantly finer diameter of fiber (13.05 ± 0.73 µm) than males (14.22 ± 1.22 µm), and infection with Eimeria spp. affected negatively fiber diameter and resistance. Our results provide data for disease surveillance and encourage further parasitological studies in vicuñas.

Helminthfauna of road-killed cougars (Puma concolor) from the Northeastern Region of São Paulo State, Brazil.

As the second-largest Neotropical carnivore, cougars (Puma concolor) are especially important for maintenance of the biodiversity and ecosystem health. Five wild adult cougars (Puma concolor), found roadkilled in highways in the Northeastern region of São Paulo, were evaluated in search for parasites. Ten species representing nine families were identified. The most prevalent helminths were Uncinaria bidens, Lagochilascaris major, Spirometra sp., and Oncicola canis, followed by Cylicospirura subaequalis, Toxascaris leonina, Taenia omissa, Echinococcus sp., Filaroides sp. and Oncicola oncicola. It is important to note that some helminths found in this study, such as L. major, Spirometra sp., O. oncicola, O. canis, Echinococcus sp., T. leonina, C. subaequalis, and Filaroides sp. are known to affect domestic carnivores, which may indicate interaction between wild and domestic hosts. This study represents a new host record for four of the species found in cougars, U. bidens, L. major, O. canis, and Filaroides sp., and new locality records for U. bidens, T. leonina, C. subaequalis, and Filaroides sp.

Metazoan parasites of Plagioscion squamosissimus, an invasive species in the Tietê River, São Paulo, Brazil.

This study focused on the characterization and analysis of communities and infra-communities of metazoan parasites of Plagioscion squamosissimus caught in Promissão Reservoir in the Tietê River in Borborema (21°39'58"S, 49°8'49"W), state of São Paulo, Brazil. Fifty adult specimens caught by professional fishermen in March 2015 were necropsied. The fish presented an average standard length of 25.2 ± 2.2 cm and average weight of 328.82 ± 89.03 g. A total of 5,227 specimens of metazoan parasites were collected: 2,880 (55.1%) adult Diplectanum piscinarius (Monogenoidea: Diplectanidae) and 2,347 (44.9%) Austrodiplostomum compactum metacercariae (Digenea, Diplostomidae), both with 100% prevalence and mean abundance of 57.6 and 46.9, respectively. Parasite diversity was low (species richness = 2), with a Simpson index (D) equal to 0.505, and low values of Brillouin (HB = 0.687) and Margalef diversity (I = 0.117) indices. Berger-Parker's index of dominance (p = 0.551) indicated a slight dominance of the monogenean parasite D. piscinarius. There was a positive correlation, assessed by Pearson coefficient between parasite abundance of D. piscinarius and standard length (r = 0.43) and weight (r = 0.51) of hosts.

Metazoan parasites of Plagioscion squamosissimus, an invasive species in the Tietê River, São Paulo, Brazil / Parasitas metazoários de Plagioscion squamosissimus, uma espécie invasora no Rio Tietê, São Paulo

Abstract This study focused on the characterization and analysis of communities and infra-communities of metazoan parasites of Plagioscion squamosissimus caught in Promissão Reservoir in the Tietê River in Borborema (21°39′58"S, 49°8′49"W), state of São Paulo, Brazil. Fifty adult specimens caught by professional fishermen in March 2015 were necropsied. The fish presented an average standard length of 25.2 ± 2.2 cm and average weight of 328.82 ± 89.03 g. A total of 5,227 specimens of metazoan parasites were collected: 2,880 (55.1%) adult Diplectanum piscinarius (Monogenoidea: Diplectanidae) and 2,347 (44.9%) Austrodiplostomum compactum metacercariae (Digenea, Diplostomidae), both with 100% prevalence and mean abundance of 57.6 and 46.9, respectively. Parasite diversity was low (species richness = 2), with a Simpson index (D) equal to 0.505, and low values of Brillouin (HB = 0.687) and Margalef diversity (I = 0.117) indices. Berger-Parker's index of dominance (p = 0.551) indicated a slight dominance of the monogenean parasite D. piscinarius. There was a positive correlation, assessed by Pearson coefficient between parasite abundance of D. piscinarius and standard length (r = 0.43) and weight (r = 0.51) of hosts.

Resumo O objetivo deste trabalho foi caracterizar e analisar as comunidades e infracomunidades de metazoários parasitos de corvinas capturadas no Reservatório de Promissão, Rio Tietê, município de Borborema (21° 67′S, 49° 14′O), Estado de São Paulo. Foram examinados 50 espécimes, capturados por pescadores profissionais no mês de março de 2015, e os parasitas coletados foram quantificados, preparados e montados para identificação taxonômica e análise das comunidades de parasitos. Os peixes analisados no estudo apresentaram comprimento padrão médio de 25,2 ± 2,2 cm e peso médio de 328,82 ± 89,03 g. Foram coletados 5227 espécimes de parasitas metazoários, sendo 2880 (55,1%) Diplectanum piscinarius (Monogenoidea: Diplectanidae) e 2347 (44,9%) metacercárias de Austrodiplostomum compactum (Digenea, Diplostomidae), ambos com prevalência de 100% e abundância parasitária de 57,6 e 46,9, respectivamente. Foi encontrada baixa diversidade parasitária (riqueza de espécies=2), com índice de Simpson (D) igual a 0,505 e baixos valores dos índices de Shannon (H'=0,688) e de diversidade de Margalef (I=0,177). O índice de dominância de Berger-Parker (d=0,551) indicou uma leve dominância do monogenético D. piscinarius. Houve correlação positiva intermediária, avaliada pelo coeficiente de Pearson, entre a abundância parasitária de D. piscinarius e comprimento padrão (r=0,43) e peso (r=0,51) dos hospedeiros.

Filarial nematodes with zoonotic potential in ring-tailed coatis (Nasua nasua Linnaeus, 1766, Carnivora: Procyonidae) and domestic dogs from Iguaçu National Park, Brazil.

Iguaçu National Park, which contains the largest remnant of Atlantic Forest in southern Brazil and Iguaçu Falls as one of its main visiting points, is a year-round attraction for thousands of domestic and international tourists. Ring-tailed coatis are generalist, opportunistic carnivores that benefit from human association. These animals are the most abundant carnivores in this park, where they come into close contact with tourists and the resident population around the park. Moreover, as the park is surrounded by human dwellings, free roaming domestic dogs are frequently present, favoring the exchange of pathogens with wild animals. Wild carnivores are known to be infected with several pathogens, from viruses to arthropods, some of them passed on by domestic carnivores. Among the nematodes that infect wild carnivores, those of the Onchocercidae family are of concern due to their zoonotic potential. The objective of this research was to assess the prevalence of filarial nematodes in coatis and dogs in Iguaçu National Park, as well as the potential impact of infection on host health and body condition. To this end, 75 coatis and 50 adult dogs were captured in the aforementioned area. Seven species of filarioids, Dirofilaria immitis, Dirofilaria repens, Acanthocheilonema reconditum, Brugia sp., Mansonella sp. and two undetermined species, confirmed by histochemical tests, were diagnosed in the area. Knott's concentration test in coatis and dogs showed a prevalence of 81.6% and 16.0%, respectively. Seven microfilarial morphotypes were diagnosed in the coatis and two morphotypes were found in the dogs. A specific immunoassay test for Dirofilaria immitis revealed the presence of D. immitis infection in 1.33% of the coatis and 22% of the domestic dogs. The parasitic infection had negligible effects on the body condition of both dog and coati hosts, but an increase was found in eosinophil counts in coatis with filarial infection, as well as decreases in hematocrit and hemoglobin in the infected domestic dogs. These findings represent new locality and host records for all the filarioids diagnosed in the area of this study, with some of the diagnosed parasites, given their zoonotic potential, representing a health risk for park visitors and the local population.

Helminth fauna of chiropterans in Amazonia: biological interactions between parasite and host.

Amazonia, the largest Brazilian biome, is one of the most diverse biomes around the world. Considering the Brazilian chiropteran species, 120 out of known 167 species are registered in Pará state, with 10 endemic species. Despite the high diversity of bats in Amazonia, studies on their parasites, especially on helminths, are scarce. Therefore, the present study aims to study the helminth fauna of different bats from the Pará state, Amazon biome, determine the descriptors of infection, and evaluate the host-parasite interactions, as well as evaluate differences in ecological indexes in accordance with the feeding guilds. The study was developed on 67 bats of 21 species captured in several areas of the Pará state. The animals were identified, divided into feeding guilds, and necropsied. The parasites obtained were identified and quantified. A total of 182 parasites were found in 20.89 % of the studied bats, representing nine species, as follows: Anenterotrema eduardocaballeroi, Anenterotrema liliputianum, Ochoterenatrema caballeroi, Tricholeiperia sp., Parahistiostrongylus octacanthus, Litomosoides guiterasi, Litomosoides brasiliensis, Capillariinae gen. sp., and Hymenolepididae gen. sp. Also, the results indicated that there was no impact of parasitism on host body condition and no relationship between sex and parasite intensity. In relation to the feeding guilds, the omnivores showed higher prevalence and mean intensity. Animals from regions closer to the equator tend to have greater richness in parasite species, but the present study revealed low diversity and richness in species. In conclusion, the ecological pattern observed for other animal groups, in which higher parasitic diversity are registered in lower latitudes, is not applicable to chiropterans from the study area.

Redescription and taxonomical considerations about Aonchotheca (Aonchotheca) pulchra n. comb. (Enoplida: Trichuridae), a nematode of Nyctinomops spp.

Pterothominx pulchra (Freitas, 1934) are little known gastric nematodes of Nyctinomops laticaudatus (Chiroptera: Molossidae). Information about the occurrence and host range of these parasites in Neotropical region is still scanty, and the only two morphological descriptions available in the literature are divergent about the presence or absence of a spiny spicular sheath in males, which may lead to incorrect taxonomical positioning, since this feature represents the main difference between the genera Pterothominx and Aonchotheca. Based on the absence of this morphological feature in specimens of this nematode obtained from N. laticaudatus and Nyctinomops macrotis bats captured in two municipalities in the state of São Paulo, Brazil, the present study reclassifies the aforementioned species in the genus Aonchotheca and allocates it to the subgenus Aonchotheca. Additional morphometric data and new host and locality records are also provided.

Redescription and taxonomical considerations about Aonchotheca (Aonchotheca) pulchra n. comb. (Enoplida: Trichuridae), a nematode of Nyctinomops spp. / Redescrição e considerações taxonômicas sobre Aonchotheca (Aonchotheca) pulchra n. comb. (Enoplida: Trichuridae), um nematódeo de Nyctinomops spp.

Pterothominx pulchra (Freitas, 1934) are little known gastric nematodes of Nyctinomops laticaudatus (Chiroptera: Molossidae). Information about the occurrence and host range of these parasites in Neotropical region is still scanty, and the only two morphological descriptions available in the literature are divergent about the presence or absence of a spiny spicular sheath in males, which may lead to incorrect taxonomical positioning, since this feature represents the main difference between the genera Pterothominx and Aonchotheca. Based on the absence of this morphological feature in specimens of this nematode obtained from N. laticaudatus and Nyctinomops macrotis bats captured in two municipalities in the state of São Paulo, Brazil, the present study reclassifies the aforementioned species in the genus Aonchotheca and allocates it to the subgenus Aonchotheca. Additional morphometric data and new host and locality records are also provided.

Pterothominx pulchra (Freitas, 1934) são nematódeos gástricos pouco conhecidos de Nyctinomops laticaudatus (Chiroptera: Molossidae). Informações referentes à ocorrência e variedade de hospedeiros desses parasitos ainda são escassas na região Neotropical. As únicas duas descrições morfológicas disponíveis na literatura são divergentes entre si quanto à presença de bainha espicular espinhosa nos machos, o que resultou no posicionamento taxonômico equivocado desta espécie, uma vez que, é a principal característica para diagnóstico dos gêneros Pterothominx e Aonchotheca. Baseado na ausência dessa característica morfológica em espécimes desse nematódeo, obtidos em morcegos N. laticaudatus e Nyctinomops macrotis capturados em dois municípios do Estado de São Paulo, Brasil, o presente estudo classifica a referida espécie no gênero Aonchotheca e a aloca no subgênero Aonchotheca, além de fornecer dados morfométricos adicionais e novos registros de hospedeiro e localidades.

Detailed morphological description of Habronema clarki Foster & Chitwood, 1937, a nematode parasite of capybaras Hydrochoerus hydrochaeris (Linnaeus, 1766) in Brazil.

The genus Habronema has four valid species, of which only two are properly known. The present study aimed to describe in detail the morphology of Habronema clarki through optical and scanning electron microscopy analyses. Our results showed that the labial morphology of this parasite is closer to H. muscae than to H. microstoma. Even so, the characteristic pseudolabia and the slightly convex border of the dorsal and ventral lips are sufficient to distinguish these nematodes. Additional morphological data are presented, thus contributing to the knowledge on this little known nematode. In addition, this study provides new locality records for this species.

Detailed morphological description of Habronema clarki Foster & Chitwood, 1937, a nematode parasite of capybaras Hydrochoerus hydrochaeris (Linnaeus, 1766) in Brazil / Descrição morfológica detalhada de Habronema clarki Foster & Chitwood, 1937, um nematódeo parasita de capivaras Hydrochoerus hydrochaeris (Linnaeus, 1766) no Brasil

The genus Habronema has four valid species, of which only two are properly known. The present study aimed to describe in detail the morphology of Habronema clarki through optical and scanning electron microscopy analyses. Our results showed that the labial morphology of this parasite is closer to H. muscae than to H. microstoma. Even so, the characteristic pseudolabia and the slightly convex border of the dorsal and ventral lips are sufficient to distinguish these nematodes. Additional morphological data are presented, thus contributing to the knowledge on this little known nematode. In addition, this study provides new locality records for this species.

O gênero Habronema tem quatro espécies válidas, das quais apenas duas são propriamente conhecidas. O presente estudo visa descrever em detalhes a morfologia de Habronema clarki por meio de microscopia eletrônica de varredura e de luz. Os resultados demonstram que a morfologia labial do parasita é mais próxima de H. muscae que de H. microstoma. Ainda assim, os pseudolábios característicos e a borda discretamente convexa dos lábios dorsal e ventral são suficientes para se diferenciar esses nematódeos. Dados morfológicos adicionais são apresentados, contribuindo ao conhecimento deste nematódeo pouco conhecido. Em adição, este estudo representa um novo registro de localidade para a espécie.

Parasitic gastritis in Cuniculus paca (Rodentia: Cuniculidae) / Gastrite parasitária em Cuniculus paca (Rodentia: Cuniculidade)

O parasitismo pelo gênero Physocephalus sp. é relatado em duas pacas naturalmente infectadas da região leste da Amazônia. Quatro animais foram necropsiados e durante a inspeção do trato digestivo, nódulos foram observados na curvatura maior do estômago. Nestes nódulos foramencontrados sete machos e sete fêmeas de parasitos do gênero Physocephalus sp, totalizando uma média de três nematóides fixos e infiltrados na submucosa de cada lesão. O exame histopatológico mostrou congestão e hemorragia intersticial na submucosa, associada com a presença de infiltradoinflamatório mononuclear. Os nematóides no local da lesão eram evidentes. Apesar de descriçõesanteriores deste patógeno em roedores, não houve qualquer relatório de lesões causadas por esta espécie de parasito. As lesões causadas pela ação do patógeno na mucosa do estômago podem afetar o processo digestivo de C. paca e levar o animal a apresentar diminuição da ingestão alimentar einatividade e conseqüente interferência no crescimento e ganho de peso, comprometendo a saúde eo bem-estar de espécies selvagens.

Chaunus ictericus (Spix, 1824) as paratenic host of the giant kidney worm Dioctophyme renale (Goeze, 1782) (Nematoda: Enoplida) in São Cristóvão district, Três Barras county, Santa Catarina state, Brazil.

Dioctophyme renale larvae have been found in cysts in the gastric wall of 5.17% (3/58) Chaunus ictericus specimens from São Cristóvão district, Três Barras municipality, Santa Catarina state, Brazil. However, larvae of this nematode were not found in sympatric Chaunus schneideri. The larvae caused a mild granulomatous reaction. This is the first report of paratenic hosts for D. renale in Brazil, and probably is also the first in the Neotropical region.

Infecçöes naturais em cervídeos (Mammalia: Cervidae) procedentes dos Estados do Mato Grosso do Sul e Säo Paulo, por nematódeos Trichostrongyloidea Cram, 1927 / Natural Trichostrongyloidea Cram, 1927 infections in deer (Mammalia: Cervidae) from the States of Mato Grosso do Sul and Säo Paulo

No período compreendido entre 1985 e 1996 foram necropsiados, para pesquisa de helmintos, 42 cervídeos, sendo sete Mazama americana, 16 M. gouazoubira, 13 Ozotoceros bezoarticus e seis Blastocerus dichotomus. Desses animais, foram colhidos 14.426 nematódeos Trichostrongyloidea, sendo 13.281 (92,06 por cento) parasitos de abomaso e 1.145 (7,94 por cento), de intestino delgado. Nesses órgäos, foram identificadas seis espécies de nematódeos: Haemonchus contortus, H. similis, Trichostrongylus axei, T. colubriformis, Cooperia punctata e C. pectinata. Todos os animais apresentaram infecçöes helmínticas por uma ou mais espécies, ocorrendo grande variaçäo na intensidade de infecçäo (1 a 4.345 nematódeos). Ainda com relaçäo à intensidade de infecçäo, os dados expressavam valores menores que 100 parasitos em 25 (59,52 por cento) animais. Os valores mais altos de intensidade média das infecçöes foram observados em M. gouazoubira (596,37 helmintos) e em O. bezoarticus (331), e os menores, em M. americana (17,57) e B. dichotomus (75,5). Os dados mais expressivos de intensidade de infecçäo, abundância e prevalência foram observados para Haemonchus (larvas de 4§ estágio), H. contortus, H. similis e T. axei. O gênero Haemonchus foi constatado em 35 animais, com prevalência de 83,33 por cento; apresentou carga parasitária de 11.616 exemplares, representando 80,52 por cento dos nematódeos verificados, sendo a maioria (8.903) constituída por formas imaturas. Por outro lado, H. similis foi a espécie predominante nas infecçöes e, portanto, a que apresentou maiores valores de abundância. Verificou-se o gênero Trichostrongylus em 24 (57,14por cento) animais, com carga parasitária de 2.444 exemplares, sendo 1.665 espécimes de T. axei, que representou 11,54 por cento da carga parasitária obtida. As seis espécies de vermes identificadas nos cervídeos säo comuns aos ruminantes domésticos nos Estados de Säo Paulo e Mato Grosso do Sul e dessa maneira nao se observou nenhuma espécie de Trichostrongyloidea exclusiva dos cervídeos