Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) in Campos do Jordão State Park, São Paulo, Brazil / Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) no Parque Estadual de Campos do Jordão, São Paulo, Brasil

The aim of this paper was recording the occurrence of the species Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) in lotic systems of the State of São Paulo. Specimens were collected in Sapucaí River, located in Campos do Jordão State Park. The mapping of geographical distribution of this species is of interest to public health since L. variegatus may be an intermediate host of Dioctophyme renale (Goeze, 1782) (Nematoda, Dioctophymatidae), a parasite of recognized zoonotic potential. Distribution data serves as a basis for environmental monitoring and evaluation, being essential to map possible cases of the disease (Dioctophimosis) and provide information to health professionals.

O objetivo deste trabalho foi registrar a ocorrência de Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) em um sistema lótico do Estado de São Paulo. Os espécimes foram coletados no rio Sapucaí, localizado no Parque Estadual de Campos do Jordão. O mapeamento da distribuição geográfica desta espécie é de interesse para saúde pública uma vez que L. variegatus pode ser um hospedeiro intermediário de Dioctophyme renale (Goeze, 1782) (Nematoda, Dioctophymatidae), parasito de reconhecido potencial zoonótico. Dados de distribuição servem de base para monitoramento e avaliação ambiental, sendo essenciais para mapear possíveis casos da doença (Dioctofimose) e fornecer informações para profissionais de saúde.

Nematódeos de interesse médico veterinário em represa urbana no município de Catalão, no sudeste do estado de Goiás, Brasil / Nematodes of veterinary medical interest in an urban reservoir in the municipality of Catalão, southeastern Goiás State, Brazil

Objetivo: realizar análises parasitológicas em amostras de solo provenientes da represa da Bica situada no município de Catalão-GO. Métodos: a área do entorno da represa foi dividida em cinco parcelas, sendo realizadas coletas em dois pontos de cada parcela, superior e inferior. Foram realizadas quatro coletas em dias alternados, totalizando 40 amostras de, aproximadamente, 50g da camada superficial do solo, com profundidade máxima de cinco centímetros. As amostras foram processadas no Setor de Diagnóstico Parasitológico do Laboratório de Biologia Molecular da Universidade Federal de Catalão (UFCAT). Para as análises parasitológicas, foram utilizados cinco métodos encontrados na literatura, Rugai, Willis, Sedimentação espontânea, Ritchie e Ritchie modificado. Resultados: pelo método de Rugai, foi possível detectar larvas rabditoides do gênero Ancylostoma e Strongyloides. Utilizando o método de Ritchie modificado, foram encontrados ovos de Ascaris lumbricoidese Ancylostoma sp. Conclusão: a presença de formas evolutivas no solo da represa indica contaminação por dejetos animais e humanos, favorecendo o estabelecimento de ciclos biológicos das espécies encontradas e de outras diferentes zoonoses. Os dados obtidos demonstram a importância de sensibilizar a população de medidas de promoção da saúde, além de ações preventivas e programas de educação em saúde.

Objective: to conduct parasitological analyses in soil samples from the Bica reservoir located in the municipality of Catalão-GO. Methods: the area around the dam was divided into five plots, and samples were collected from two points in each plot, upper and lower. Four samples were collected on alternate days, totaling 40 samples of approximately 50g of topsoil, with a maximum depth of five centimeters. The samples were processed in the Parasitological Diagnostic Sector of the Molecular Biology Laboratory of the Federal University of Catalão (UFCAT). For the parasitological analyses, we used five methods found in the literature, Rugai, Willis, spontaneous sedimentation, Ritchie, and modified Ritchie. Results: by the Rugai method, it was possible to detect rhabditoid larvae of the genus Ancylostoma and Strongyloides. Using the modified Ritchie method, eggs of Ascaris lumbricoidesand Ancylostoma sp were found. Conclusion: the presence of evolutive forms in the soil of the reservoir indicates contamination by animal and human waste, favoring the establishment of biological cycles of the species found and of other different zoonoses. The data obtained demonstrated the importance of raising the population's awareness of health promotion measures besides preventive actions and health education programs.

Inquérito epidemiológico sobre Lagoquilascaríase em Felinos da Serra Gaúcha / Epidemiological survey on Lagoquilascariasis in felines of Serra Gaucha

O nematoide Lagochilascaris sp. pertencente à família Ascarididae é um parasito cujo o hospedeiro definitivo pode ser o gato. Considerada uma zoonose rara na medicina veterinária, a lagoquilascaríase é responsável por causar lesões luminais e possui um tropismo particular pela região cervical e cabeça. A infecção ocorre através da ingestão da carne de animais silvestres mal cozida pelo homem e através da caça pelos felinos. Este trabalho tem como objetivo realizar um levantamento dos casos de lagoquilascaríase ocorridos em gatos domésticos nas cidades de Bento Gonçalves, Farroupilha e Caxias do Sul, localizadas na região da Serra Gaúcha. Foi realizada uma pesquisa através de questionário encaminhado por e-mail, durante os meses de abril a julho de 2020, a 44 médicos veterinários dos municípios de Bento Gonçalves, Farroupilha e Caxias do Sul, sendo 13 (29,54%) veterinários de Bento Gonçalves, 10 (22,73%) de Farroupilha e 21 (47,73%) de Caxias do Sul. Destes profissionais, 17 (38,63%) já atenderam casos de animais parasitados por este nematódeo; 9 (20,45%) em Bento Gonçalves; 3 (6,81%) em Farroupilha e 5 (11,36%) em Caxias do Sul. No total foram atendidos 36 casos de lagoquilascaríase no período de 2016 a 2020, sendo que a maior ocorrência foi na cidade de Bento Gonçalves, com 25 casos, seguida por Caxias do Sul com 6 casos e Farroupilha com apenas 5 casos relatados. Apesar da literatura considerar a lagoquilascaríase uma doença rara, este levantamento mostra que há vários casos acontecendo na espécie felina na Serra Gaúcha.

The nematode Lagochilascaris sp. belonging to the family Ascarididae is a parasite whose definitive host may be the cat. Considered a rare zoonosis in veterinary medicine, lagochilascariasis is responsible for causing luminal lesions and has a particular tropism for the cervical region and head. Infection occurs through the ingestion of undercooked meat from wild animals by humans and through hunting by felines. This work aims to carry out a survey of cases of lagochilascariasis that occurred in domestic cats in the cities of Bento Gonçalves, Farroupilha and Caxias do Sul, located in the Serra Gaúcha region. A survey was carried out through a questionnaire sent by email, during the months of April to July 2020, to 44 veterinarians from the municipalities of Bento Gonçalves, Farroupilha and Caxias do Sul, of which 13 (29.54%) were veterinarians from Bento. Gonçalves, 10 (22.73%) from Farroupilha and 21 (47.73%) from Caxias do Sul. Of these professionals, 17 (38.63%) have already treated cases of animals parasitized by this nematode; 9 (20.45%) in Bento Gonçalves; 3 (6.81%) in Farroupilha and 5 (11.36%) in Caxias do Sul. In total, 36 cases of lagochilascariasis were treated in the period from 2016 to 2020, with the highest occurrence being in the city of Bento Gonçalves, with 25 cases, followed by Caxias do Sul with 6 cases and Farroupilha with only 5 reported cases. Although the literature considers lagochilascariasis a rare disease, this survey shows that there are several cases happening in feline species in Serra Gaúcha.

Excretion of Histomonas meleagridis following experimental co-infection of distinct chicken lines with Heterakis gallinarum and Ascaridia galli.

BACKGROUND: Histomonosis is a severe re-emerging disease of poultry caused by Histomonas meleagridis, a protozoan parasite which survives in the environment via the cecal worm Heterakis gallinarum. Following infection, the parasites reside in the ceca and are excreted via host feces. In the present work, male birds of conventional broiler (Ross 308, R), layer (Lohmann Brown Plus, LB) and a dual-purpose (Lohmann Dual, LD) chicken line were infected with 250 embryonated eggs of Ascaridia galli and Heterakis gallinarum, respectively, with the latter nematode harboring Histomonas meleagridis, to investigate a co-infection of nematodes with the protozoan parasite in different host lines. METHODS: In weekly intervals, from 2 to 9 weeks post infection (wpi), individual fecal samples (n = 234) from the chickens were collected to quantify the excretion of H. meleagridis by real-time PCR and to determine the number of nematode eggs per gram (EPG) in order to elucidate excretion dynamics of the flagellate and the nematodes. This was further investigated by indirect detection using plasma samples of the birds to detect antibodies specific for H. meleagridis and worms by ELISA. The infection with H. meleagridis was confirmed by histopathology and immunohistochemistry to detect the flagellate in the cecum of representing birds. RESULTS: The excretion of H. meleagridis could already be observed from the 2nd wpi in some birds and increased to 100% in the last week of the experiment in all groups independent of the genetic line. This increase could be confirmed by ELISA, even though the number of excreted H. meleagridis per bird was generally low. Overall, histomonads were detected in 60% to 78% of birds with temporary differences between the different genetic lines, which also showed variations in the EPG and worm burden of both nematodes. CONCLUSIONS: The infection with H. gallinarum eggs contaminated with H. meleagridis led to a permanent excretion of the flagellate in host feces. Differences in the excretion of H. meleagridis in the feces of genetically different host lines occurred intermittently. The excretion of the protozoan or its vector H. gallinarum was mostly exclusive, showing a negative interaction between the two parasites in the same host.

Comparative transcriptomic analysis of candidate effectors to explore the infection and survival strategy of Bursaphelenchus xylophilus during different interaction stages with pine trees.

BACKGROUND: The pine wood nematode (PWN), Bursaphelenchus xylophilus, is a devastating pathogen of many Pinus species in China. The aim of this study was to understand the interactive molecular mechanism of PWN and its host by comparing differentially expressed genes and candidate effectors from three transcriptomes of B. xylophilus at different infection stages. RESULTS: In total, 62, 69 and 46 candidate effectors were identified in three transcriptomes (2.5 h postinfection, 6, 12 and 24 h postinoculation and 6 and 15 d postinfection, respectively). In addition to uncharacterized pioneers, other candidate effectors were involved in the degradation of host tissues, suppression of host defenses, targeting plant signaling pathways, feeding and detoxification, which helped B. xylophilus survive successfully in the host. Seven candidate effectors were identified in both our study and the B. xylophilus transcriptome at 2.5 h postinfection, and one candidate effector was identified in all three transcriptomes. These common candidate effectors were upregulated at infection stages, and one of them suppressed pathogen-associated molecular pattern (PAMP) PsXEG1-triggered cell death in Nicotiana benthamiana. CONCLUSIONS: The results indicated that B. xylophilus secreted various candidate effectors, and some of them continued to function throughout all infection stages. These various candidate effectors were important to B. xylophilus infection and survival, and they functioned in different ways (such as breaking down host cell walls, suppressing host defenses, promoting feeding efficiency, promoting detoxification and playing virulence functions). The present results provide valuable resources for in-depth research on the pathogenesis of B. xylophilus from the perspective of effectors.

Diarreia em bezerros no sul do Rio Grande do Sul em um período de 34 anos / Diarrhea in calves in Southern Rio Grande do Sul in a period of 34 years

O objetivo deste trabalho foi descrever os dados de um estudo retrospectivo nos registros de 34 anos atividade de um laboratório de diagnóstico sobre as causas de diarreia em bezerros na região sul do Rio Grande do Sul. Foram revisados os protocolos de necropsia e materiais desta espécie encaminhados ao Laboratório Regional de Diagnóstico da Faculdade de Veterinária da Universidade Federal de Pelotas. Foram diagnosticados 94 casos de bezerros com diarreia, destes, 44,7% foram de causas parasitárias e 34,0% de causas bacterianas. Diarreia de causa parasitária foi a mais importante na região sul do Rio Grande do Sul e afetou bezerros de três a 12 meses de idade. A ocorrência de diarreia em animais mesmo lactentes pode estar associada a fatores ambientais e a forma de manejo no qual esses animais são mantidos. As enfermidades bacterianas foram, também, importantes causas de diarreia em bezerros de até três meses de idade na região.

The objective of this work was to describe the data from a retrospective study in the records of 34 years of activity in a diagnostic laboratory on the diarrhea causes of in calves in the southern region of Rio Grande do Sul. All necropsy protocols and materials received in the Regional Diagnostic Laboratory of the Veterinary School of the Federal University of Pelotas were reviewed. Ninety-four cases of calves with diarrhea were diagnosed, of these, 44.7% were caused by parasitic infections and 34.0% by bacterial infections. Parasites as cause of diarrhea was the most important diagnostic in southern Rio Grande do Sul and affected calves from three to 12 months of age. The occurrence of diarrhea in animals even infants may be associated with environmental factors and the form of management that these animals are kept. Bacterial diseases are also important causes of diarrhea in calves up to three months of age in the region.

First Occurrence of Eustrongylides spp. (Nematoda: Dioctophymatidae) in a Subalpine Lake in Northwest Italy: New Data on Distribution and Host Range.

The genus Eustrongylides includes nematodes that infect fish species and fish-eating birds inhabiting freshwater ecosystems. Nematodes belonging to the genus Eustrongylides are potentially pathogenic for humans; infection occurs after the consumption of raw or undercooked fish. In the two-year period 2019-2020, a total of 292 fish belonging to eight species were examined for the occurrence of Eustrongylides spp. from Lake San Michele, a small subalpine lake in northwest Italy. The prevalence of infestation was 18.3% in Lepomis gibbosus, 16.7% in Micropterus salmoides, and 10% in Perca fluviatilis. The other five fish species (Ameiurus melas, Ictalurus punctatus, Squalius cephalus, Carassius carassius, and Scardinius erythrophthalmus) were all negative for parasite presence. There were no significant differences in prevalence between the three fish species (Fisher's exact test; p = 0.744). The mean intensity of infestation ranged from 1 (M. salmoides and P. fluviatilis) to 1.15 (L. gibbosus), and the mean abundance ranged from 0.1 (P. fluviatilis) to 0.28 (L. gibbosus). There were significant differences in the infestation site between the four muscle quadrants (anterior ventral, anterior dorsal, posterior ventral, and posterior dorsal) and the visceral cavity (Kruskal-Wallis test; p = 0.0008). The study findings advance our knowledge about the distribution and host range of this parasite in Italy.

Odds ratios and hurdle models: a long-term analysis of parasite infection patterns in endangered young-of-the-year suckers from Upper Klamath Lake, Oregon, USA.

We used odds ratios and a hurdle model to analyze parasite co-infections over 25 years on >20,000 young-of-the year of endangered Shortnose and Lost River Suckers. Host ecologies differed as did parasite infections. Shortnose Suckers were more likely to be caught inshore and 3-5 times more likely to have Bolbophorus spp. and Contracaecum sp. infections, and Lost River Suckers were more likely to be caught offshore and approximately three times more likely to have Lernaea cyprinacea infections. An observed peak shift seems likely to be due to a lower host size limit for Bolbophorus spp. (13.6 mm) compared with L. cyprinacea (23.4 mm). The large data set allowed us to generate strong hypotheses: (i) that a major marsh restoration project had unintended consequences that resulted in an increase in infections; (ii) that co-infection with Bolbophorus spp. increased the odds of infection by L. cyprinacea and Contracaecum sp.; (iii) that significant declines in the odds of infection over approximately 25 days were due to parasite-induced host mortality; (iv) that the fish's small size relative to L. cyprinacea and Contracaecum sp. might be directly lethal; (v) that the absence of L. cyprinacea infections in the early 1990s was associated with good year-class production of the suckers; and (vi) that parasites might increase the odds of vagrancy from the nursery ground.

Phenotypic plasticity and local adaptation in freeze tolerance: Implications for parasite dynamics in a changing world.

Marshallagia marshalli is a multi-host gastrointestinal nematode that infects a variety of artiodactyl species from temperate to Arctic latitudes. Eggs of Marshallagia are passed in host faeces and develop through three larval stages (L1, L2, and L3) in the environment. Although eggs normally hatch as L1s, they can also hatch as L3s. We hypothesised that this phenotypic plasticity in hatching behaviour may improve fitness in subzero and highly variable environments, and this may constitute an evolutionary advantage under current climate change scenarios. To test this, we first determined if the freeze tolerance of different free-living stages varied at different temperatures (-9 °C, -20 °C and -35 °C). We then investigated if there were differences in freeze tolerance of M. marshalli eggs sourced from three discrete, semi-isolated, populations of wild bighorn and thinhorn sheep living in western North America (latitudes: 40°N, 50°N, 64°N). The survival rates of eggs and L3s were significantly higher than L1s at -9 °C and -20 °C, and survival of all three stages decreased significantly with increasing freeze duration and decreasing temperature. The survival of unhatched L1s was significantly higher than the survival of hatched L1s. There was no evidence of local thermal adaptation in freeze tolerance among eggs from different locations. We conclude that developing to the L3 in the egg may result in a fitness advantage for M. marshalli, with the egg protecting the more vulnerable L1 under freezing conditions. This phenotypic plasticity in life-history traits of M. marshalli might be an important capacity, a potential exaptation capable of enhancing parasite fitness under temperature extremes.

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.

Small RNAs in parasitic nematodes - forms and functions.

Small RNAs are important regulators of gene expression. They were first identified in Caenorhabditis elegans, but it is now apparent that the main small RNA silencing pathways are functionally conserved across diverse organisms. Availability of genome data for an increasing number of parasitic nematodes has enabled bioinformatic identification of small RNA sequences. Expression of these in different lifecycle stages is revealed by small RNA sequencing and microarray analysis. In this review we describe what is known of the three main small RNA classes in parasitic nematodes - microRNAs (miRNAs), Piwi-interacting RNAs (piRNAs) and small interfering RNAs (siRNAs) - and their proposed functions. miRNAs regulate development in C. elegans and the temporal expression of parasitic nematode miRNAs suggest modulation of target gene levels as parasites develop within the host. miRNAs are also present in extracellular vesicles released by nematodes in vitro, and in plasma from infected hosts, suggesting potential regulation of host gene expression. Roles of piRNAs and siRNAs in suppressing target genes, including transposable elements, are also reviewed. Recent successes in RNAi-mediated gene silencing, and application of small RNA inhibitors and mimics will continue to advance understanding of small RNA functions within the parasite and at the host-parasite interface.

Helminth-microbiota cross-talk - A journey through the vertebrate digestive system.

The gastrointestinal (GI) tract of vertebrates is inhabited by a vast array of organisms, i.e., the microbiota and macrobiota. The former is composed largely of commensal microorganisms, which play vital roles in host nutrition and maintenance of energy balance, in addition to supporting the development and function of the vertebrate immune system. By contrast, the macrobiota includes parasitic helminths, which are mostly considered detrimental to host health via a range of pathogenic effects that depend on parasite size, location in the GI tract, burden of infection, metabolic activity, and interactions with the host immune system. Sharing the same environment within the vertebrate host, the GI microbiota and parasitic helminths interact with each other, and the results of such interactions may impact, directly or indirectly, on host health and homeostasis. The complex relationships occurring between parasitic helminths and microbiota have long been neglected; however, recent studies point towards a role for these interactions in the overall pathophysiology of helminth disease, as well as in parasite-mediated suppression of inflammation. Whilst several discrepancies in qualitative and quantitative modifications in gut microbiota composition have been described based on host and helminth species under investigation, we argue that attention should be paid to the systems biology of the gut compartment under consideration, as variations in the abundances of the same population of bacteria inhabiting different niches of the GI tract may result in varying functional consequences for host physiology.

Comparison of direct and indirect techniques for evaluating endoparasite infections in wild-caught newts (Taricha torosa and T. granulosa).

Studies of amphibian parasites have increased over the past 20 yr, in part because of their role in amphibian population declines and deformities. Such patterns underscore the importance of non-lethal methods for detecting and quantifying endoparasitic infections. The goal of this study was to compare results of indirect methods (fecal smears and fecal floats) with quantitative necropsies to detect endoparasitic infections in adult newts. In 2015, we collected fecal samples from 68 adult newts (Taricha granulosa and T. torosa) in the East Bay region of California and used fecal smears, sodium nitrate fecal flotation solution, and Sheather's sugar flotation solution to assess infection (i.e. the presence and/or abundance of a parasite). Across all methods, we detected 3 protozoans (Eimeria tarichae, Tritrichomonas sp., and Balantidium sp.) and 3 nematodes (Rhabdias tarichae, Cosmocercoides variabilis, and Chabaudgolvania sp.). Based on generalized linear mixed models, the likelihood of detection varied between hosts (with T. torosa showing more overall infection relative to T. granulosa) and by assessment method: while fecal smears were more sensitive in detecting protozoans, comprehensive necropsies were the most reliable for quantifying infections of R. tarichae. Nonetheless, both the likelihood of R. tarichae detection within fecal samples as well as the number of infectious stages observed correlated strongly with infection intensity from necropsy, highlighting the utility of non-lethal assessment methods. The overall congruence between indirect methods and gross necropsy helps to validate the use of less-invasive methods for parasite detection and abundance, especially for sensitive or protected host taxa such as amphibians.

Human Migration and the Spread of the Nematode Parasite Wuchereria bancrofti.

The human disease lymphatic filariasis causes the debilitating effects of elephantiasis and hydrocele. Lymphatic filariasis currently affects the lives of 90 million people in 52 countries. There are three nematodes that cause lymphatic filariasis, Brugia malayi, Brugia timori, and Wuchereria bancrofti, but 90% of all cases of lymphatic filariasis are caused solely by W. bancrofti (Wb). Here we use population genomics to reconstruct the probable route and timing of migration of Wb strains that currently infect Africa, Haiti, and Papua New Guinea (PNG). We used selective whole genome amplification to sequence 42 whole genomes of single Wb worms from populations in Haiti, Mali, Kenya, and PNG. Our results are consistent with a hypothesis of an Island Southeast Asia or East Asian origin of Wb. Our demographic models support divergence times that correlate with the migration of human populations. We hypothesize that PNG was infected at two separate times, first by the Melanesians and later by the migrating Austronesians. The migrating Austronesians also likely introduced Wb to Madagascar where later migrations spread it to continental Africa. From Africa, Wb spread to the New World during the transatlantic slave trade. Genome scans identified 17 genes that were highly differentiated among Wb populations. Among these are genes associated with human immune suppression, insecticide sensitivity, and proposed drug targets. Identifying the distribution of genetic diversity in Wb populations and selection forces acting on the genome will build a foundation to test future hypotheses and help predict response to current eradication efforts.

Estudo preliminar de Hysterothylacium deardorffoverstreetorum (Nematoda, Raphidascarididae) parasitando pargo, Pagrus pagrus, coletados no litoral do Estado do Rio de Janeiro, RJ, Brasil / Preliminary study of Hysterothylacium deardorffoverstreetorum (Nematoda, Raphidascarididae) parasitizing red porgy, Pagrus pagrus, collected in the coast of the State of Rio de Janeiro, RJ, Brazil

O pargo, Pagrus pagrus, possui carne muito apreciada na culinária brasileira. Peixes marinhos podem albergar larvas de nematoides anisaquídeos, que podem causar anisaquidose no ser humano, se ingerirem peixes crus ou mal cozidos. Entre os meses de fevereiro e julho de 2017, foram coletados 115 peixes em mercados de pescados no Município de Arraial do Cabo, RJ. Os peixes foram necropsiados e 17 estavam parasitados por anisaquídeos. Os sítios de infecção foram intestino, fígado e cavidade abdominal. Os nematoides foram processados seguindo as técnicas helmintológicas e identificados em taxonomicamente como Hysterothylacium deardorffoverstreetorum. O objetivo foi identificar a nível específico os nematoides coletados das lesões das serosas de P. pagrus e relatar alterações patológicas encontradas.

Parasites of Gymnodactylus darwinii Gray, 1845 (Squamata, Phyllodactylidae) from an Atlantic Rainforest fragment.

Gymnodactylus darwinii is an endemic lizard from Atlantic Rainforest. Ecological aspects of your parasitic fauna are still unknown. Therefore, the goal of the present study was to know the composition of parasitic fauna of G. darwinii in an Atlantic Rainforest fragment, as well to test the influence of the size, sex and seasonality on parasitological indices. The study was carried out in two conservation units: Mata do Camucim and Mata do Tapacurá, both located in the municipality of São Lourenço da Mata, Pernambuco state, northeast region of Brazil. Sixty-five specimens were collected, of which 39 (569%) were parasitized by cystacanths of Acanthocephala (prevalence 43%; mean intensity 4 ± 9.9; mean abundance 3.82 ± 7.87), Geckobia sp. (Acari, Pterygosomatidae) (prevalence 30.7%; mean intensity 4 ± 15.0; mean abundance 3.74 ± 9.54), Physaloptera sp. larvae (Nematoda, Physalopteridae) (prevalence 4.6%; mean intensity 1 ± 0.47; mean abundance 0.06 ± 0.47) and Paradistomum rabusculum (Trematoda, Dicrocoeliidae) (prevalence 1.2%; mean intensity 1; mean abundance 0.02). Acanthocephalans presented a significant relation with the animal length (r² = 0.31, p = 0.006, n = 28). Infestation by Geckobia sp. was more frequent during the dry season (BLM: p = 0.001), while the infection by Acanthocephalans was frequent in dry and rainy seasons, with no significant variation (BLM: p = 0.78). In addition, the most prevalent parasites showed no significant difference in relation to sex: males and females showed similar infestation intensity by Geckobia sp. (BLM: p = 0.31) and infection by Acanthocephala (BLM: p = 0.34). This is the first study about the parasitic ecology of G. darwinii, representing a significant contribution to the conservation of this species and the ecosystem in which they inhabit.

Molecular detection and quantification of slug parasitic nematodes from the soil and their hosts.

Terrestrial gastropod molluscs are widely distributed and are well known as pests of many types of plants that are notoriously difficult to control. Many species of nematodes are able to parasitize land snails and slugs, but few of them are lethal to their host. Species and/or populations of mollusc-parasitic nematodes (MPNs) that kill their hosts are promising for biological control purposes. The recent discovery of new nematode species of the genus Phasmarhabditis in Europe and the associations between Alloionema spp. and slugs are expanding the possibilities of using MPNs as control agents. However, very little is known about the distribution and ecology of these species. Using molecular techniques based on qPCR methods for quick identification and quantification of various species of MPN isolated directly from the soil or from infected hosts can assist in providing information on their presence and persistence, as well as the composition of natural assemblages. Here, we developed new primers and probes for five species of the genus Phasmarhabditis and one species of the genus Alloionema. We employed these novel molecular techniques and implemented a published molecular set to detect MPN presence in soil samples coming from natural and agricultural areas in Switzerland. We also developed a method that allows the detection and quantification of Phasmarhabditis hermaphrodita directly from the tissues of their slug host in a laboratory experiment. The new molecular approaches were optimized to a satisfactory limit of detection of the species, with only few cross-amplifications with closely related species in late cycles (>32). Using these tools, we detected MPNs in 7.5% of sampled sites, corresponding to forest areas (P. hermaphrodita and Alloionema appendiculatum) and wheat-oriented agricultural areas (Phasmarhabditis bohemica). Moreover, we confirmed that the method can be used to detect the presence of P. hermaphrodita inside slug hosts, with more detections in the susceptible slug Deroceras larvae compared to the resistant Arion vulgaris. These primers/probe sets provide a novel and quick tool to identify MPNs from soil samples and infected slugs without having to culture and retrieve all nematode life stages, as well as a new tool to unravel the ecology of nematode-slug complexes.

Decreased nematode clearance and anti-phosphorylcholine-specific IgM responses in mannose-binding lectin-deficient mice.

Brugia malayi is a nematode that causes human lymphatic filariasis. Previously, we showed that mannose-binding lectin (MBL)-A is necessary for clearance of B. malayi microfilariae in mice and presence of MBL-A is linked with maximal levels of parasite-specific IgM. Common human MBL gene polymorphisms result in low MBL expression and lead to recurring bacterial infections. Furthermore, these low-expressing human MBL polymorphisms result in greatly increased susceptibility to lymphatic filarial infection. Indeed, gain of new filarial infections over a 30-year period are 10-fold higher in people with low, compared to high, MBL-expression phenotypes. Human MBL closely resembles mouse MBL-C, rather than MBL-A; therefore, we examined the role of mouse MBL-C in clearance of microfilariae. Absence of MBL-C alone, or both MBL-A and -C, resulted in delayed clearance of microfilariae and reduced parasite-specific IgM in mice. There were few profound changes in B cell sub-populations or in the ability of MBL-deficient mice to respond to T-dependent or T-independent antigens. However, absence of MBL-A and/or MBL-C resulted in reduced IgM to phosphorylcholine, a constituent of filarial and bacterial antigens, suggesting that inability to form proficient antibody responses to this moiety leads to lack of microfilarial clearance and overall susceptibility to filariasis.

Comparative evolutionary histories of fungal proteases reveal gene gains in the mycoparasitic and nematode-parasitic fungus Clonostachys rosea.

BACKGROUND: The ascomycete fungus Clonostachys rosea (order Hypocreales) can control several important plant diseases caused by plant pathogenic fungi and nematodes. Subtilisin-like serine proteases are considered to play an important role in pathogenesis in entomopathogenic, mycoparasitic, and nematophagous fungi used for biological control. In this study, we analysed the evolutionary histories of protease gene families, and investigated sequence divergence and regulation of serine protease genes in C. rosea. RESULTS: Proteases of selected hypocrealean fungal species were classified into families based on the MEROPS peptidase database. The highest number of protease genes (590) was found in Fusarium solani, followed by C. rosea with 576 genes. Analysis of gene family evolution identified non-random changes in gene copy numbers in the five serine protease gene families S1A, S8A, S9X, S12 and S33. Four families, S1A, S8A, S9X, and S33, displayed gene gains in C. rosea. A gene-tree / species-tree reconciliation analysis of the S8A family revealed that the gene copy number increase in C. rosea was primarily associated with the S08.054 (proteinase K) subgroup. In addition, regulatory and predicted structural differences, including twelve sites evolving under positive selection, among eighteen C. rosea S8A serine protease paralog genes were also observed. The C. rosea S8A serine protease gene prs6 was induced during interaction with the plant pathogenic species F. graminearum. CONCLUSIONS: Non-random increases in S8A, S9X and S33 serine protease gene numbers in the mycoparasitic species C. rosea, Trichoderma atroviride and T. virens suggests an involvement in fungal-fungal interactions. Regulatory and predicted structural differences between C. rosea S8A paralogs indicate that functional diversification is driving the observed increase in gene copy numbers. The induction of prs6 expression in C. rosea during confrontation with F. graminearum suggests an involvement of the corresponding protease in fungal-fungal interactions. The results pinpoint the importance of serine proteases for ecological niche adaptation in C. rosea, including a potential role in the mycoparasitic attack on fungal prey.

Infected host macerate enhances entomopathogenic nematode movement towards hosts and infectivity in a soil profile.

Vertical dispersal and infectivity of the infective juveniles (IJs) of three entomopathogenic nematodes (EPNs), Steinernema carpocapsae, S. feltiae, and Heterorhabditis bacteriophora, were tested in the presence or absence of cadaver macerate of nematode-infected Galleria mellonella. Infected host macerate applied on the top of column surface induced higher numbers of IJs to move to the bottom of the column for all three species, indicating a dispersal-enhancing effect of host cadaver on IJs. Among the three EPNs, H. bacteriophora was the most responsive to host macerate, followed by S. feltiae, and S. carpocapsae was the least. Also, more IJs of H. bacteriophora invaded Tenebrio molitor hosts at the bottom of soil columns in the presence of host macerate compared with the treatment without cadaver macerate. These findings suggest enhanced dispersal and/or infectivity of all three EPNs may be leveraged toward superior biocontrol efficacy.