Metabolism and immune memory in invertebrates: are they dissociated?

Since the discovery of specific immune memory in invertebrates, researchers have investigated its immune response to diverse microbial and environmental stimuli. Nevertheless, the extent of the immune system's interaction with metabolism, remains relatively enigmatic. In this mini review, we propose a comprehensive investigation into the intricate interplay between metabolism and specific immune memory. Our hypothesis is that cellular endocycles and epigenetic modifications play pivotal roles in shaping this relationship. Furthermore, we underscore the importance of the crosstalk between metabolism and specific immune memory for understanding the evolutionary costs. By evaluating these costs, we can gain deeper insights into the adaptive strategies employed by invertebrates in response to pathogenic challenges. Lastly, we outline future research directions aimed at unraveling the crosstalk between metabolism and specific immune memory. These avenues of inquiry promise to illuminate fundamental principles governing host-pathogen interactions and evolutionary trade-offs, thus advancing our understanding of invertebrate immunology.

First Report of Mermithidae (Enoplea: Mermithida) Parasitizing Adult Stable Flies in Japan.

Mermithidae is a family of nematodes that parasitize a wide range of invertebrates worldwide. Herein, we report nematodes that were unexpectedly found in three of 486 adult stable flies (Stomoxys calcitrans) captured from three farms (F1, F2, and F3) in different regions of Gifu Prefecture, Japan. We aimed to characterize these nematodes both at the morphological and molecular level. Morphological studies revealed that the nematodes were juveniles of Mermithidae. Phylogenetic analysis based on 18S and 28S rDNA indicated that the mermithids from farms F1 and F2 could be categorized into the same cluster as Ovomermis sinensis and Hexamermis sp., whereas the mermithid from farm F3 clustered with Amphimermis sp. Additionally, these mermithids could be categorized within the same clusters as related mermithids detected in Japan that parasitize various arthropod orders. Our findings suggest that these stable flies may have been parasitized by mermithids already present in the region and that genetically distinct species of mermithids occur across Japan. To the best of our knowledge, this is the first report of mermithids parasitizing adult stable flies in Japan.

Beyond parasitism: Exploring the microbial profile of Haemonchus contortus and its predilection site (abomasum) in Kashmir Merino sheep.

Gastrointestinal helminth infection, particularly by Haemonchus contortus, poses significant challenges to sheep farming worldwide. While anthelmintic drugs have been traditional control measures, the emergence of resistance calls for alternative strategies. Understanding the interaction between parasites, host, and their microbiome is crucial for management of helminth infection. This study intricately explores the interactions between microbial communities in Kashmir Merino sheep infected with H. contortus, to understand the complex interplay between host, parasite, and their microbiome. Sheep abomasal contents and H. contortus were collected from infected and control groups, processed for DNA extraction, and subjected to metagenomic sequencing of the 16 S rRNA gene. Downstream analysis unveils distinct microbial patterns, where Proteobacteria were dominant in H. contortus, while Bacteroidota and Firmicutes prevailed in the sheep abomasum. The revelation of unique genera and shifts in diversity indices underscored helminth-induced disruptions in the host. Beta diversity analysis further showed significant variations in bacterial profiles, providing insights into the intricate host, parasite, and microbiome dynamics. Additionally, this study elucidated the presence of pathogenic bacteria within H. contortus, accentuating their potential role in exacerbating sheep health issues. This finding underscores the complexity of the host-parasite-microbiome interaction showing helminth-induced microbiome alterations of the host.

Expression of IL-10 and TGF-ß1 in horses experimentally infected with T. equi merozoites is associated with antibody production but not modulation of pro-inflammatory responses.

Theileria equi (T. equi) is an apicomplexan parasite that causes severe hemolytic anemia in equids. Presently, there is inadequate knowledge of the immune responses induced by T. equi in equid hosts impeding understanding of the host parasite relationship and development of potent vaccines for control of T. equi infections. The objective of this study was to evaluate the host-parasite dynamics between T. equi merozoites and infected horses by assessing cytokine expression during primary and secondary parasite exposure, and to determine whether the pattern of expression correlated with clinical indicators of disease. Our findings showed that the expression of pro-inflammatory cytokines was very low and inconsistent during both primary and secondary infection. There was also no correlation between the symptoms observed during primary infection and expression of the cytokines. This suggests that the symptoms might have occurred primarily due to hemolysis and likely not the undesirable effects of pro-inflammatory responses. However, IL-10 and TGF-ß1 were highly expressed in both phases of infection, and their expression was linked to antibody production but not moderation of pro-inflammatory cytokine responses.

Consistent Negative Correlations between Parasite Infection and Host Body Condition Across Seasons Suggest Potential Harmful Impacts of Salmincola markewitschi on Wild White-Spotted Charr, Salvelinus leucomaenis.

Assessing the impacts of parasites on wild fish populations is a fundamental and challenging aspect of the study of host-parasite relationships. Salmincola, a genus of ectoparasitic copepods, mainly infects salmonid species. This genus, which is notorious in aquaculture, damages host fishes, but its impacts under natural conditions remain largely unknown or are often considered negligible. In this study, we investigated the potential impacts of mouth-attaching Salmincola markewitschi on white-spotted charr (Salvelinus leucomaenis) through intensive field surveys across four seasons using host body condition as an indicator of harmful effects. The prevalence and parasite abundance were highest in winter and gradually decreased in summer and autumn, which might be due to host breeding and/or wintering aggregations that help parasite transmissions. Despite seasonal differences in prevalence and parasite abundance, consistent negative correlations between parasite abundance and host body condition were observed across all seasons, indicating that the mouth-attaching copepods could reduce the body condition of the host fish. This provides field evidence suggesting that S. markewitschi has a potential negative impact on wild white-spotted charr.

Response of Hypothenemus hampei Ferrari (Coleoptera: Curculionidae: Scolytinae) parasitized by the nematode Metaparasitylenchus hypothenemi Poinar (Tylenchida: Allantonematidae) to different colors of light.

Metaparasitylenchus hypothenemi is a nematode that naturally parasitizes Hypothenemus hampei in a coffee-producing region in Chiapas, Mexico. This study investigated changes in the attraction of parasitized borers to light. We compared the attraction of adult H. hampei females (parasitized and uninfected) to 14 different light wavelengths (350-670 nm) with a control (570 nm, yellow) under laboratory conditions. The response ranges of non-parasitized and parasitized borers were 370-650 nm and 340-650 nm, respectively. The attraction curve showed a similar shape in both borer groups (parasitized and non-parasitized), but a wide wavelength range (380-590 nm) attracted more parasitized than non-parasitized borers. The maximum response of the uninfected borers occurred at 520 nm (green), while parasitized borers exhibited three response peaks (380 nm, violet; 460 nm, blue; 520 nm, green). Parasitized borers were significantly more attracted to green light (520 nm) than to the control. The altered attraction to light in borers parasitized by M. hypothenemi is discussed from the perspective of possible host manipulation and the natural prevalence of this parasite.

The plasticity of immune memory in invertebrates.

Whether specific immune protection after initial pathogen exposure (immune memory) occurs in invertebrates has long been uncertain. The absence of antibodies, B-cells and T-cells, and the short lifespans of invertebrates led to the hypothesis that immune memory does not occur in these organisms. However, research in the past two decades has supported the existence of immune memory in several invertebrate groups, including Ctenophora, Cnidaria, Nematoda, Mollusca and Arthropoda. Interestingly, some studies have demonstrated immune memory that is specific to the parasite strain. Nonetheless, other work does not provide support for immune memory in invertebrates or offers only partial support. Moreover, the expected biphasic immune response, a characteristic of adaptive immune memory in vertebrates, varies within and between invertebrate species. This variation may be attributed to the influence of biotic or abiotic factors, particularly parasites, on the outcome of immune memory. Despite its critical importance for survival, the role of phenotypic plasticity in immune memory has not been systematically examined in the past two decades. Additionally, the features of immune responses occurring in diverse environments have yet to be fully characterized.

The intersection of host in vivo metabolism and immune responses to infection with kinetoplastid and apicomplexan parasites.

SUMMARYProtozoan parasite infection dramatically alters host metabolism, driven by immunological demand and parasite manipulation strategies. Immunometabolic checkpoints are often exploited by kinetoplastid and protozoan parasites to establish chronic infection, which can significantly impair host metabolic homeostasis. The recent growth of tools to analyze metabolism is expanding our understanding of these questions. Here, we review and contrast host metabolic alterations that occur in vivo during infection with Leishmania, trypanosomes, Toxoplasma, Plasmodium, and Cryptosporidium. Although genetically divergent, there are commonalities among these pathogens in terms of metabolic needs, induction of the type I immune responses required for clearance, and the potential for sustained host metabolic dysbiosis. Comparing these pathogens provides an opportunity to explore how transmission strategy, nutritional demand, and host cell and tissue tropism drive similarities and unique aspects in host response and infection outcome and to design new strategies to treat disease.

First Report of Root-knot Nematode, Meloidogyne enterolobii on Passiflora edulis in Yulin, China.

Passion fruit (Passiflora edulis), a medicinal plant, was introduced into China in the early 19th century, is mainly cultivated in southern provinces (Liang et al. 2019). During March 2023, a survey was carried out and 167 samples were taken from passion fruit cultivated area in Yulin (22.6570263°E; 110.1765019°N) apart from the planting base appeared yellow leaves, stunted growth, and distinctive galls on the roots. Within the galls, Meloidogyne sp. females and egg masses were observed. From the rhizosphere soil, second-stage juveniles (J2) were extracted, and population density was 105/500 g soil. The species was determined to be Meloidogyne enterolobii based on morphological characteristics, including female perineal pattern, and genetic analyses. Female (n = 10) perineal patterns showed oval shape, with coarse and smooth striae, dorsal arch rounded to square, and lateral lines not distinct. The male head cap was high and rounded, with the head region only slightly set off from the body, knobs large, ovoid to rounded. The measurements of males (n = 10) included body length, 1,230.7 ± 244.94 (997 to 1,569) µm; a, 38.58 ± 7.8 (33.45 to 47.05) µm; c, 113.03 ± 26.22 (80.82 to 144.23) µm; stylet, 15.68 ± 1.1 (14.5 to 17.4) µm; spicules, 31.83 ± 2.84 (28.69 to 36.1) µm; tail, 11.09 ± 1.72 (8.02 to 13.38) µm; and gubernaculum length, 8.34 ± 0.28 (8.11 to 8.98) µm. Measurements of J2 (n = 20) included body length, 455.75 ± 44.94 (381 to 512) µm; a, 26.32 ± 3.89 (18.18 to 32.70) µm; c, 8.56 ± 1.2 (6.36 to 10.80) µm; stylet, 12.44 ± 0.76 (11.2 to 13.8) µm; DGO, 3.65 ± 0.54 (2.84 to 4.68) µm; tail, 53.89 ± 6.36 (39.8 to 62.2) µm; and hyaline tail terminus, 11.77 ± 2.83 (7.14 to 16.2) µm. These morphological characteristics are similar to those reported in the original description of M. enterolobii (Yang and Eisenback 1983). The sequences of the partial ITS region was amplified with V5367 (5'-TTGATTACGTCCCTGCCCTTT-3') and 26S (5'-TTTCACTCGCCGTTACTAAGG-3') primers (Vrain et al. 1992). The region between cytochrome oxidase subunit II (COII) and the 16S rRNA mitochondrial DNA (mtDNA COII) was also amplified with the primers C2F3 (5'-GGTCAATGTTCAGAAATTTGTGG-3') (Powers and Harris 1993) and MRH106 (5'-AATTTCTAAAGACTTTTCTTAGT-3') (Stanton et al. 1997). The ITS region yielded a fragment of 757 bp (OR072957) and mtDNA COII of 706 bp (OR078415). A BLAST search indicated the sequences were 100% identical to several sequences of M. enterolobii (MT406250, MH756127 and AY831967, MN269940, respectively). To confirm pathogenicity, 20 passion fruit (P. edulis Sim. f. flavicarpa) 30-day-old seedlings were transplanted into pots with an autoclaved mixture of sand and field soil (3:1) and maintained in the glasshouse at 25 ± 2°C with 65 ± 5% relative humidity. After eight weeks, fifteen plants were inoculated with 500 J2/pot (nematode culture collected from the original field), and another five uninoculated plants served as a control. Two months later, aboveground symptoms were similar to those observed in the field. Nematode reproduction occurred and root galls were observed. The reproduction factor (nematode final population density/initial population density) was 4.8. The disease caused by M. enterolobii was severe in Yulin city of Guangxi. Guangxi is an important area for passion fruit culture, with about 2000 ha, which is responsible for two-thirds of China production (Xing et al. 2020). This is the first record of P. edulis natural infection with M. enterolobii in the Yulin City of Guangxi, China.

Preliminary evidence for chaotic signatures in host-microbe interactions.

Host-microbe interactions constitute dynamical systems that can be represented by mathematical formulations that determine their dynamic nature and are categorized as deterministic, stochastic, or chaotic. Knowing the type of dynamical interaction is essential for understanding the system under study. Very little experimental work has been done to determine the dynamical characteristics of host-microbe interactions, and its study poses significant challenges. The most straightforward experimental outcome involves an observation of time to death upon infection. However, in measuring this outcome, the internal parameters and the dynamics of each particular host-microbe interaction in a population of interactions are hidden from the experimentalist. To investigate whether a time-to-death (time-to-event) data set provides adequate information for searching for chaotic signatures, we first determined our ability to detect chaos in simulated data sets of time-to-event measurements and successfully distinguished the time-to-event distribution of a chaotic process from a comparable stochastic one. To do so, we introduced an inversion measure to test for a chaotic signature in time-to-event distributions. Next, we searched for chaos in the time-to-death of Caenorhabditis elegans and Drosophila melanogaster infected with Pseudomonas aeruginosa or Pseudomonas entomophila, respectively. We found suggestions of chaotic signatures in both systems but caution that our results are preliminary and highlight the need for more fine-grained and larger data sets in determining dynamical characteristics. If validated, chaos in host-microbe interactions would have important implications for the occurrence and outcome of infectious diseases, the reproducibility of experiments in the field of microbial pathogenesis, and the prediction of microbial threats.IMPORTANCEIs microbial pathogenesis a predictable scientific field? At a time when we are dealing with coronavirus disease 2019, there is intense interest in knowing about the epidemic potential of other microbial threats and new emerging infectious diseases. To know whether microbial pathogenesis will ever be a predictable scientific field requires knowing whether a host-microbe interaction follows deterministic, stochastic, or chaotic dynamics. If randomness and chaos are absent from virulence, there is hope for prediction in the future regarding the outcome of microbe-host interactions. Chaotic systems are inherently unpredictable, although it is possible to generate short-term probabilistic models, as is done in applications of stochastic processes and machine learning to weather forecasting. Information on the dynamics of a system is also essential for understanding the reproducibility of experiments, a topic of great concern in the biological sciences. Our study finds preliminary evidence for chaotic dynamics in infectious diseases.

Heartworm and seal louse: Trends in prevalence, characterisation of impact and transmission pathways in a unique parasite assembly on seals in the North and Baltic Sea.

The ectoparasitic seal louse, Echinophthirius horridus infects harbour (Phoca vitulina) and grey seals (Halichoerus grypus) in the North and Baltic Sea. The endoparasitic heartworm Acanthocheilonema spirocauda parasitizes the right heart and blood vessels of harbour seals. The complete lifecycle of the heartworm is not entirely understood although the seal louse is assumed to serve as vector for its transmission. Knowledge about the impact of both parasite species on host health are scarce. In this study, necropsy data and archived parasites of harbour and grey seals in German waters were analysed to determine long-term seal louse (SLP) and heartworm prevalence (HWP) from 2014 to 2021. Histology, microbiology and scanning electron microscopy (SEM) were applied on seal louse infected and uninfected skin to investigate associated lesions and the health impact. During the study period, HWP in harbour seals was 13%, the SLP in harbour seals was 4% and in grey seals 10%. HWP of harbour seals was significantly higher during the winter months compared to the summer. SLP in adults was significantly higher in comparison to juvenile harbour seals. SLP varied significantly between grey seals from the North and Baltic Sea. Filarial nematodes were detected in the haemocoel, pharynx, and intestine of E. horridus highlighting the seal louse as vector for heartworms. Alopecia and folliculitis were associated with the attachment posture of E. horridus and microbiological investigations isolated bacteria commonly associated with folliculitis.

Carbohydrate metabolism evaluation of terrestrial snail Subulina octona (Gastropoda, Subulinidae) experimentally infected by the Paratanaisia bragai digenetic trematode (Digenea, Eucotylidae).

Among the effects of the larval development of digenetic trematodes on their intermediate hosts, changes in the carbohydrate metabolism in the snails stand out. The aim of this study was to analyze, every 10 days after infection (d.p.i.), the effects of Paratanaisia bragai infection on the glycogen content in the digestive gland and cephalopedal mass in Subulina octona snail, and also verify the glucose concentration and the enzyme D- and L-lactate dehydrogenase activity (EC1.1.1.27 and EC1.1.1.28) (LDH) and the concentration of some metabolites(oxalic, succinic, pyruvic and lactic acid) presents in the hemolymph. Histochemical analisys were also performed. We verified a total increase of 54.81% in glucose concentration in infected snails and an oscillating pattern in the glycogen content in the cephalopedal mass and in the digestive gland. LDH activity shows an increase of 10 d.p.i. (+ 74.32%) and 40 d.p.i. (+ 47.81%) and decrease at 20 d.p.i. and 30 d.p.i. The concentrations of oxalic, succinic and pyruvic acids showed significant and progressive reductions; however, lactic acid had a significant increase. Histological and histochemical analysis showed a tissue disorganization in the cephalopedal mass of infected snails and morphological changes in the digestive gland. These results confirm that infection causes metabolic pathway changes in the snails due to activation of an alternative anaerobic pathway for producing energy, indicated by the increased lactic acid content and LDH activity.

Could the acute strongyloides venezuelensis infection cause non-reversible host morphological changes? / A infecção aguda por strongyloides venezuelensis pode causar alterações morfológicas irreversíveis no hospedeiro? / ¿Puede la infección aguda por las strongyloides venezuelensis causar cambios morfológicos irreversibles en el hostal?

Although research has investigated the host-parasite relationship in Strongyloides venezuelensis infection in the scope of its immunological implications, the morphological consequences of this response for the host organism are yet to be explored. Our objective was to perform an organ morphometric analysis in Wistar rats infected with the intestinal parasite Strongyloides venezuelensis compared with infected rats treated with ivermectin. Twenty-six animals composed three groups: control (non-infected), infected (infected with 2,000 Strongyloides venezuelensis larvae), and infected treated (infected with 2,000 Strongyloides venezuelensis larvae and treated with ivermectin). All rodents were killed 21 days after infection and morphometric analysis of different organs was performed. The results showed significantly higher body and fecal weight in the infected-treated group. The weight of the small intestine increased considerably in the infected group and decreased in the infected-treated group. Pancreas, right kidney, and heart volume increased in the infected group compared with the control group. Despite treatment, the volumes of the stomach, brain, and left kidney increased in both the infected groups compared with the control group indicating the possibility of non- reversible host morphological adaptations. S. venezuelensis infection can augment both, volume and weight of organs ­ not necessarily related to the Strongyloides expulsion process ­ even if the acute infection had been in remission. A potential explanation for these host adaptations, including the occurrence of organ plasticity, are briefly discussed. The following steps encompass a histological analysis to verify the occurrence of hypertrophy/hyperplasia and observe if such morphological alterations remain after infection.

Embora pesquisas tenham investigado a relação parasita-hospedeiro na infecção por Strongyloides venezuelensis no âmbito de suas implicações imunológicas, as consequências morfológicas dessa resposta para o organismo hospedeiro ainda precisam ser exploradas. Nosso objetivo foi realizar uma análise morfométrica de órgãos em ratos Wistar infectados com o parasito intestinal Strongyloides venezuelensis em comparação com ratos infectados tratados com ivermectina. Vinte e seis animais compuseram três grupos: controle (não infectados), infectados (infectados com 2.000 larvas de Strongyloides venezuelensis) e tratados infectados (infectados com 2.000 larvas de Strongyloides venezuelensis e tratados com ivermectina). Todos os roedores foram sacrificados 21 dias após a infecção e a análise morfométrica de diferentes órgãos foi realizada. Os resultados mostraram peso corporal e fecal significativamente maior no grupo tratado infectado. O peso do intestino delgado aumentou consideravelmente no grupo infectado e diminuiu no grupo infectado tratado. O volume do pâncreas, rim direito e coração aumentou no grupo infectado em comparação com o grupo controle. Apesar do tratamento, os volumes do estômago, cérebro e rim esquerdo aumentaram em ambos os grupos infectados em comparação com o grupo controle, indicando a possibilidade de adaptações morfológicas não reversíveis do hospedeiro. A infecção por S. venezuelensis pode aumentar tanto o volume quanto o peso dos órgãos ­ não necessariamente relacionado ao processo de expulsão de Strongyloides ­ mesmo que a infecção aguda estivesse em remissão. Uma possível explicação para essas adaptações do hospedeiro, incluindo a ocorrência de plasticidade de órgãos, é brevemente discutida. As etapas a seguir compreendem uma análise histológica para verificar a ocorrência de hipertrofia/hiperplasia e observar se tais alterações morfológicas permanecem após a infecção.

Aunque la investigación ha investigado la relación parásito-huésped en la infección con Strongyloides venezuelensis dentro del alcance de sus implicaciones inmunológicas, aún deben explorarse las consecuencias morfológicas de esta respuesta para el organismo huésped. Nuestro objetivo fue realizar un análisis morfométrico de órganos en ratas Wistar infectadas con el parásito intestinal Strongyloides venezuelensis en comparación con ratas infectadas tratadas con ivermectina. Veintiséis animales conformaron tres grupos: control (no infectado), infectados (infectados con 2.000 larvas de Strongyloides venezuelensis) y tratados infectados (infectados con 2.000 larvas de Strongyloides venezuelensis y tratados con ivermectina). Todos los roedores fueron sacrificados 21 días después de la infección y se realizó un análisis morfométrico de diferentes órganos. Los resultados mostraron un peso corporal y fecal significativamente mayor en el grupo tratado infectado. El peso del intestino delgado aumentó considerablemente en el grupo infectado y disminuyó en el grupo tratado. El volumen de páncreas, riñón derecho y corazón aumentó en el grupo infectado en comparación con el grupo control. A pesar del tratamiento, los volúmenes de estómago izquierdo, cerebro y riñón aumentaron en ambos grupos infectados en comparación con el grupo control, lo que indica la posibilidad de adaptaciones morfológicas irreversibles del huésped. La infección con S. venezuelensis puede aumentar tanto el volumen como el peso de los órganos -no necesariamente relacionados con el proceso de expulsión de Strongyloides-, incluso si la infección aguda estaba en remisión. Se discute brevemente una posible explicación de estas adaptaciones del huésped, incluida la aparición de plasticidad de los órganos. Los siguientes pasos incluyen un análisis histológico para comprobar la hipertrofia/hiperplasia y para ver si estos cambios morfológicos permanecen después de la infección.

A Structural Analysis of Host-Parasite Interactions in Achatina fulica (Giant African Snail) Infected with Angiostrongylus cantonensis.

Angiostrongylus cantonensis is a nematode parasite that resides in the pulmonary arteries of rodents, serving as its definitive hosts. The life cycle involves several species of non-marine gastropods as intermediate hosts, and the African giant snail Achatina fulica is considered one of the most important around the world. Experimental data concerning A. cantonensis infection in the African giant snail remains notably limited. This helminth causes eosinophilic meningitis or meningoencephalitis in humans, representing an emergent zoonosis in Brazil. Understanding the host-parasite relationship through the application of new tools is crucial, given the complex interaction between zoonosis and the intricate mechanisms involving wild/human hosts, parasite adaptation, and dispersion. The objective of this study was to employ SEM as a novel methodology to understand the structural organization of the host tissue, particularly the granuloma formation. This sheds light on the complex balance between A. fulica and A. cantonensis. Nine three-month-old snails were randomly selected and exposed for 24 h to a concentration of 2000 L1/dose of A. cantonensis. A necropsy was performed 37 days after the infection, and the samples were examined using light and scanning electron microscopy (SEM). The histopathological results revealed third-stage larvae of A. cantonensis associated with granulomas distributed throughout the head-foot mass, mantle, and kidney. Scanning electron microscopy of the histological section surface showed that the granuloma is surrounded by a cluster of spherical particles, which are distributed in the region bordering the larvae. This reveal details of the nematode structure, demonstrating how this methodology can enhance our understanding of the role of granulomas in molluscan tissue. The structural characteristics of granuloma formation in A. fulica suggest it as an excellent invertebrate host for A. cantonensis. This relationship appears to provide protection to the parasite against the host's immune defense system while isolating the snail's tissue from potential exposure to nematode antigens.

Evaluation of the reproductive profile of Subulina octona (Gastropoda, Subulinidae) experimentally infected by Paratanaisia bragai (Digenea, Eucotylidae) / Avaliação do perfil reprodutivo de Subulina octona (Gastropoda, Subulinidae) infectada experimentalmente por Paratanaisia bragai (Digenea, Eucotylidae)

Abstract Snails infected by trematodes may increase or decrease their reproductive activity in response to the presence of infection. Our aim was to verify the reproductive alterations in Subulina octona after infection by Paratanaisia bragai. The infected snails were individually exposed for 24 hours to 20 parasite eggs and four groups were formed (10, 20, 30 and 40 d.p.i.- days after infection), along with control groups. Every 10 days, the number of eggs in the reproductive tract, number of eggs hatched, galactogen content and histopathological changes were evaluated. The reproductive in the control and infected snails presented an alternating pattern, where periods of high production of eggs and newly hatched were followed by periods of low production. However, in relation to the amount of galactogen, both control and infected groups followed the same pattern of variation. In the histology, we observed the presence of male and female gametes with marked reduction in the number of oocytes. The results indicate that the intra-snail development of the parasite affects the reproductive biology of the host.

Resumo Moluscos infectados por trematódeos podem aumentar ou diminuir sua atividade reprodutiva em resposta à presença da infecção. Nosso objetivo foi verificar as alterações reprodutivas de Subulina octona após a infecção por Paratanaisia bragai. Os moluscos infectados foram individualmente expostos durante 24 horas a 20 ovos do parasito e quatro grupos foram formados (10, 20, 30 e 40 d.p.i. - dias pós infecção), com respectivos grupos controle. A cada 10 dias, o número de ovos no trato reprodutivo, o número de ovos eclodidos, o conteúdo de galactogênio e alterações histopatológicas eram avaliadas. O padrão reprodutivo nos moluscos controle e infectados evidenciou um comportamento alternante, nos quais períodos de alta produção de ovos e filhotes foram seguidos por períodos de baixa produção. No entanto, em relação ao conteúdo de galactogênio, moluscos controle e infectados seguiram o mesmo padrão de variação. Na histologia, observamos a presença de gametas masculinos e femininos com acentuada redução no número de óocitos. Os resultados indicam que o desenvolvimento intramolusco do parasito afeta a biologia reprodutiva do hospedeiro.

Accumulation of oocysts of Cryptosporidium parvum in Biomphalaria glabrata (Pulmonata: Planorbidae) under experimental conditions

Abstract INTRODUCTION: Cryptosporidium oocysts are easily transported to various aquatic environments. The objective of this study was to evaluate B. glabrata mollusks exposed to food containing C. parvum oocysts. METHODS: Six experimental groups were used with B. glabrata either exposed or not to C. parvum oocysts. Microscopic and molecular diagnostics were conducted in water samples and tissues of B. glabrata. RESULTS: By light microscopy, C. parvum oocysts were identified in the water of the exposed groups. C. parvum DNA was not detected in water but was detected in tissue samples. CONCLUSIONS: Further studies should be conducted under natural conditions.

Streblid bat flies (Diptera) and other ectoparasites on bats (Mammalia: Chiroptera) from French Guiana / Moscas estréblidas (Diptera) e outros ectoparasitos de morcegos (Mammalia: Chiroptera) na Guiana Francesa

Abstract: Recent field surveys of bats (Chiroptera) in various localities of French Guiana have been accompanied by the collection and preservation of ectoparasites, mainly bat flies (Diptera: Streblidae and Nycteribiidae). Most specimens of ectoparasites was collected haphazardly during the course of bats inventories, but systematic surveys on the whole chiropteran community were realized at five opportunities. Concerning Streblidae, 813 individuals have been examined, which represent 46 species and/or subspecies belonging to 15 genera and 6 taxa for confirmation and/or future description. For Nycteribiidae, 44 individuals of 3 identified species and 2 for confirmation and/or future description. Other ectoparasites have been found (Hemiptera and acarids), which are also listed with details on their bat-host, place and date of collect. For six species of bats in which at least 10 animals were carrying ectoparasites, a brief description of the frequencies of their ectoparasites provides some preliminary characteristics of their infracommunities.

Resumo: Pesquisas de campo recentes de morcegos (Chiroptera) em várias localidades da Guiana Francesa foram acompanhadas pela coleta e preservação de ectoparasitas, principalmente moscas ectoparasitas (Diptera: Streblidae e Nycteribiidae). A maioria dos espécimes de ectoparasitos foi coletada aleatoriamente durante o curso dos inventários de morcegos, mas pesquisas sistemáticas em toda a comunidade de quirópteros foram realizadas em cinco oportunidades. Sobre Streblidae, 813 indivíduos foram examinados, dos quais representam 46 espécies e/ou subespécies pertencentes a 15 gêneros e 6 táxons para posterior confirmação específica e/ou descrição. Para Nycterbiidae, 44 indivíduos de 3 espécies e 2 para posterior confirmação específica e/ou descrição. Outros ectoparasitos foram coletados (hemípteros polictenídeos e ácaros), os quais também foram listados com detalhes sobre seus hospedeiros, localidade e data de coleta. Para seis espécies de morcegos com mais de 10 morcegos infestados a descrição da composição de cada infracomunidade encontrada e sua frequência são apresentados.

Infracommunities of bat flies (Diptera: Streblidae and Nycteribiidae) of bats (Mammalia: Chiroptera) in three conservation units in the State of Amapá, Brazil / Infracomunidades de moscas ectoparasitas (Diptera: Streblidae e Nycteribiidae) de morcegos (Mammalia: Chiroptera) em três unidades de conservação no Estado do Amapá, Brasil

Abstract: Diptera belonging to the families Nycteribiidae and Streblidae are hematophagous ectoparasites, exclusively of bats. The Amapá State is located in the North Region of Brazil. The Amapá represents one of with the lowest rates of deforestation in the country, with approximately 80% of the territory preserved. Within the State, there are conservation units, Floresta Nacional do Amapá (FNA), Parque Nacional Montanhas do Tumucumaque (PNMT) and Reserva de desenvolvimento Sustentável do Rio Iratapurú (RDSI). These areas represent priority areas for the Conservation of Amazonian Biodiversity. Recently in Amapá studied on the diversity and distribution of bats, however, there are no records of associated arthropod ectoparasites. Therefore, the objective was to describe the pattern of association of Nycteribiidae and Streblidae species on bats in three protected areas of Amapá. Bats were collected through mist nets, where each host had its body visually revised and the Diptera collected were identified through a specific bibliography. One thousand and eighty- six individuals of bats flies were identified, distributed in 52 species (Streblidae = 49 and Nycteribiidae = three). Among the three infracommunities, the PNMT infracommunities was the largest found with abundance and richness of bats flies. All species found, represent new occurrences for the Amapá, being these, 18 new records for the North Region and seven new records for Brazil.

Resumo: Dípteros pertencentes as famílias Nycteribiidae e Streblidae são ectoparasitos hematófagos, sendo exclusivamente de morcegos. O estado do Amapá localiza-se na região Norte do Brasil e representa um dos estados com as menores taxas de desmatamento do país, com aproximadamente 80% do território preservado. Dentro do Estado, existem as unidades de conservação, a Floresta Nacional do Amapá (FNA), o Parque Nacional Montanhas do Tumucumaque (PNMT) e a Reserva de Desenvolvimento Sustentável do Rio Iratapurú (RDS) que representam áreas prioritárias para a Conservação da Biodiversidade da Amazônia. Estudos sobre a diversidade e a distribuição de morcegos têm sido estudada recentemente no Amapá, no entanto, não existem registros de artrópodes ectoparasitos associados. Sendo assim, o objetivo foi descrever padrão de associação das espécies de Nycteribiidae e Streblidae sobre morcegos em três unidades de conservação do Amapá. Os morcegos foram coletados por meio de redes de neblina, onde cada hospedeiro teve seu corpo revisado visualmente e os dípteros coletados foram identificados através de bibliografia específica. Foram identificados 1086 indivíduos de moscas ectoparasitas, distribuídos em 52 espécies (Streblidae = 49 e Nycteribiidae = três). Entre as três infracomunidades, a infracomunidade de PNMT foi a maior encontrada tanto com relação a abundancia como em riqueza de dípteros ectoparasitas. Todas as espécies encontradas, representam novas ocorrências para o Estado do Amapá, sendo essas, 18 novos registros para a Região Norte e sete novos registros para o Brasil.

Evaluation of the reproductive profile of Subulina octona (Gastropoda, Subulinidae) experimentally infected by Paratanaisia bragai (Digenea, Eucotylidae)

Abstract Snails infected by trematodes may increase or decrease their reproductive activity in response to the presence of infection. Our aim was to verify the reproductive alterations in Subulina octona after infection by Paratanaisia bragai. The infected snails were individually exposed for 24 hours to 20 parasite eggs and four groups were formed (10, 20, 30 and 40 d.p.i.- days after infection), along with control groups. Every 10 days, the number of eggs in the reproductive tract, number of eggs hatched, galactogen content and histopathological changes were evaluated. The reproductive in the control and infected snails presented an alternating pattern, where periods of high production of eggs and newly hatched were followed by periods of low production. However, in relation to the amount of galactogen, both control and infected groups followed the same pattern of variation. In the histology, we observed the presence of male and female gametes with marked reduction in the number of oocytes. The results indicate that the intra-snail development of the parasite affects the reproductive biology of the host.

Resumo Moluscos infectados por trematódeos podem aumentar ou diminuir sua atividade reprodutiva em resposta à presença da infecção. Nosso objetivo foi verificar as alterações reprodutivas de Subulina octona após a infecção por Paratanaisia bragai. Os moluscos infectados foram individualmente expostos durante 24 horas a 20 ovos do parasito e quatro grupos foram formados (10, 20, 30 e 40 d.p.i. dias pós infecção), com respectivos grupos controle. A cada 10 dias, o número de ovos no trato reprodutivo, o número de ovos eclodidos, o conteúdo de galactogênio e alterações histopatológicas eram avaliadas. O padrão reprodutivo nos moluscos controle e infectados evidenciou um comportamento alternante, nos quais períodos de alta produção de ovos e filhotes foram seguidos por períodos de baixa produção. No entanto, em relação ao conteúdo de galactogênio, moluscos controle e infectados seguiram o mesmo padrão de variação. Na histologia, observamos a presença de gametas masculinos e femininos com acentuada redução no número de óocitos. Os resultados indicam que o desenvolvimento intramolusco do parasito afeta a biologia reprodutiva do hospedeiro.

Evaluation of clinical signs, parasitemia, hematologic and biochemical changes in cattle experimentally infected with Trypanosoma vivax / Avaliação dos sinais clínicos, parasitemia e alterações hematológicas e bioquímicas de bovinos experimentalmente infectados peloTrypanosoma vivax

Abstract Infections by Trypanosoma vivax cause great losses to livestock in Africa and Central and South Americas. Outbreaks due this parasite have been occurred with increasing frequency in Brazil. Knowledge of changes caused byT. vivax during the course of this disease can be of great diagnostic value. Thus, clinical signs, parasitemia, hematologic and biochemical changes of cattle experimentally infected by this hemoparasite were evaluated. Two distinct phases were verified during the infection – an acute phase where circulating parasites were seen and then a chronic phase where fluctuations in parasitemia were detected including aparasitemic periods. A constant reduction in erythrocytes, hemoglobin and packed cell volume (PVC) were observed. White blood cells (WBC) showed pronounced changes such as severe neutropenia and lymphopenia during the acute phase of the illness. Decreases in cholesterol, albumin, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and increases in glucose, globulin, protein, and alkaline phosphatase (ALP) were observed. The “Lins” isolate of T. vivax showed pathogenicity for cattle, and intense parasitemia was detected in the early stages of infection. Circulating parasites were detected for about two months. The most evident laboratory abnormalities were found in WBC parameters, including thrombocytopenia.

Resumo Infecções pelo Trypanosoma vivax causam grandes prejuízos à pecuária na África e Américas Central e do Sul. Surtos devido a este protozoário têm ocorrido com frequência cada vez maior no Brasil. O conhecimento das alterações provocadas pelo T. vivax durante a evolução desta enfermidade podem ser de grande valia para o auxílio no diagnóstico. Para tanto foram estudados os sinais clínicos, parasitemia, alterações hematológicas e bioquímicas em bovinos experimentalmente infectados por este hemoparasito. Foram verificadas duas fases distintas durante a infecção, uma aguda onde parasitos circulantes foram vistos durante todo o período, e posteriormente uma crônica, onde foram detectadas flutuações na parasitemia, com períodos aparasitêmicos. Foi verificada constante diminuição da contagem global de eritrócitos, teor de hemoglobina e volume globular (VG). O leucograma revelou leucopenia por neutropenia e linfopenia durante a fase aguda da enfermidade. Foram observados diminuição do colesterol, albumina, aspartato aminotransferase (AST), lactato desidrogenase (LDH) e aumento da glicose, globulinas, proteínas e fosfatase alcalina (FA). O isolado “Lins” de T. vivax apresentou patogenicidade para bovinos, verificando-se parasitemia intensa nos estágios iniciais da infecção, sendo detectados parasitas circulantes por aproximadamente dois meses. As alterações laboratoriais mais evidentes foram encontradas nos parâmetros do leucograma, ainda destacando-se um quadro de trombocitopenia.