International journal for parasitology最新文献

{"title":"Parasite exchange and hybridisation at a wild-feral-domestic interface","authors":"William J. Smith ,&nbsp;Michał T. Jezierski ,&nbsp;Jenny C. Dunn ,&nbsp;Sonya M. Clegg","doi":"10.1016/j.ijpara.2023.06.005","DOIUrl":"10.1016/j.ijpara.2023.06.005","url":null,"abstract":"<div><p>Interactions between wild, feral, and domestic animals are of economic and conservation significance. The pigeon <em>Columba livia</em> is a synanthropic species in a feral form, but it also includes the rare Rock Dove. <em>Columba livia</em> is an important player at the wild-domestic interface, acting as a carrier of avian diseases, and the feral form threatens Rock Doves with extinction via hybridisation. Despite its abundance, little is known about drivers of disease prevalence in <em>C. livia</em>, or how disease and hybridisation represent synergistic threats to Rock Doves. We focused on infection by the parasite <em>Trichomonas</em>, first collating prevalence estimates in domestic and free-living populations from relevant studies of <em>C. livia</em>. Second, we characterised variation in the diversity and prevalence of <em>Trichomonas</em> among three <em>C. livia</em> populations in the United Kingdom: a feral, a Rock Dove, and a feral-wild hybrid population. Across multiple continents, free-living pigeons had lower <em>Trichomonas</em> infection than captive conspecifics, but the effect was weak. Environmental factors which could impact <em>Trichomonas</em> infection status did not explain variation in infection among populations. Among the British populations, strain diversity varied, and there was lower parasite prevalence in Rock Doves than feral pigeons. Individual infection status was not explained by the available covariates, including hybrid score and site. The drivers of <em>Trichomonas</em> prevalence are unclear, perhaps due to idiosyncratic local-scale drivers. However, given the population-level variation in both infection prevalence and introgressive hybridisation, the potential combined effects could accelerate the extinction of the Rock Dove. Further study of the synergistic effects of multiple types of biotic interactions at the wild-feral-domestic interface is warranted, especially where vagile, globally distributed and superabundant animals are involved.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 14","pages":"Pages 797-808"},"PeriodicalIF":4.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0020751923001558/pdfft?md5=29bb4e5e8fa24b94e9f4466b5333061a&pid=1-s2.0-S0020751923001558-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9885922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The same genotype of Sarcocystis neurona responsible for mass mortality in marine mammals induced a clinical outbreak in raccoons (Procyon lotor) 10 years later","authors":"Aditya Gupta ,&nbsp;Mary Duncan ,&nbsp;Amy R. Sweeny ,&nbsp;Larissa S. de Araujo ,&nbsp;Oliver C.H. Kwok ,&nbsp;Benjamin M. Rosenthal ,&nbsp;Asis Khan ,&nbsp;Michael E. Grigg ,&nbsp;Jitender P. Dubey","doi":"10.1016/j.ijpara.2023.08.001","DOIUrl":"10.1016/j.ijpara.2023.08.001","url":null,"abstract":"<div><p>Here, we report the first known outbreak of clinical protozoal myeloencephalitis in naturally infected raccoons by the parasite <em>Sarcocystis neurona</em>. The North American opossum (<em>Didelphis virginiana</em>) and the South American opossum (<em>Didelphis albiventris</em>) are its known definitive hosts. Several other animal species are its intermediate or aberrant hosts. The raccoon (<em>Procyon lotor</em>) is considered the most important intermediate host for <em>S. neurona</em> in the USA. More than 50% of raccoons in the USA have sarcocysts in their muscles, however clinical sarcocystosis in raccoons is rare. In 2014, 38 free-living raccoons were found dead or moribund on the grounds of the Saint Louis Zoo, Missouri, USA. Moribund individuals were weak, lethargic, and mildly ataxic; several with oculo-nasal discharge. Seven raccoons were found dead and 31 were humanely euthanized. Postmortem examinations were conducted on nine raccoons. Neural lesions compatible with acute sarcocystosis were detected in eight raccoons. The predominant lesions were meningoencephalitis and perivascular mononuclear cells. Histologic evidence for the Canine Distemper Virus was found in one raccoon. Schizonts and merozoites were present in the encephalitic lesions of four raccoons. Mature sarcocysts were present within myocytes of five raccoons. In six raccoons, <em>S. neurona</em> schizonts and merozoites were confirmed by immunohistochemical staining with <em>S. neurona</em>-specific polyclonal antibodies. Viable <em>S. neurona</em> was isolated from the brains of two raccoons by bioassay in interferon gamma gene knockout mice and in cell cultures seeded directly with raccoon brain homogenate. Molecular characterization was based on raccoon no. 68. Molecular characterization based on multi-locus typing at five surface antigens (<em>SnSAG1-5</em>-<em>6, SnSAG3</em> and <em>SnSAG4</em>) and the <em>ITS-1</em> marker within the ssrRNA locus, using DNA isolated from bradyzoites released from sarcocysts in a naturally infected raccoon (no. 68), confirmed the presence of <em>S. neurona</em> antigen type I, the same genotype that caused a mass mortality event in which 40 southern sea otters stranded dead or dying within a 3 week period in April 2004 with <em>S. neurona</em>-associated disease. An expanded set of genotyping markers was next applied. This study reports the following new genotyping markers at 18S rRNA, 28S rRNA, <em>COX1</em>, <em>ITS-1</em>, <em>RON1</em>, <em>RON2</em>, <em>GAPDH1</em>, <em>ROP20</em>, <em>SAG2</em>, <em>SnSRS21</em> and <em>TUBA1</em> markers<em>.</em> The identity of <em>Sarcocystis</em> spp. infecting raccoons is discussed.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 14","pages":"Pages 777-785"},"PeriodicalIF":4.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10548144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bird species with wider geographical ranges have higher blood parasite diversity but not prevalence across the African-Eurasian flyway","authors":"Mary La Chapelle,&nbsp;Marcello Ruta,&nbsp;Jenny C. Dunn","doi":"10.1016/j.ijpara.2023.06.002","DOIUrl":"10.1016/j.ijpara.2023.06.002","url":null,"abstract":"<div><p>Avian blood parasites, from the genera <em>Plasmodium, Haemoproteus</em> and <em>Leucocytozoon</em>, are predicted to alter their range and prevalence as global temperatures change, and host and vector ranges shift. Understanding large-scale patterns in the prevalence and diversity of avian malaria and malaria-like parasites is important due to an incomplete understanding of their effects in the wild, where studies suggest even light parasitaemia can potentially cause rapid mortality, especially in naïve populations. We conducted phylogenetically controlled analyses to test for differences in prevalence and lineage diversity of haemoparasite infection (for <em>Plasmodium</em>, <em>Haemoproteus</em> and <em>Leucocytozoon</em>) in and between resident and migratory species along the African-Eurasian flyway. To test whether migratory strategy or range size drives differences in parasite prevalence and diversity between resident and migrant species, we included three categories of resident species: Eurasian only (<em>n</em> = 36 species), African only (<em>n</em> = 41), and species resident on both continents (<em>n</em> = 17), alongside intercontinental migrants (<em>n</em> = 64), using a subset of data from the MalAvi database comprising 27,861 individual birds. We found that species resident on both continents had a higher overall parasite diversity than all other categories. Eurasian residents had lower <em>Plasmodium</em> diversity than all other groups, and both migrants and species resident on both continents had higher <em>Haemoproteus</em> diversity than both African and Eurasian residents. <em>Leucocytozoon</em> diversity did not differ between groups. Prevalence patterns were less clear, with marked differences between genera. Both <em>Plasmodium</em> and <em>Leucocytozoon</em> prevalence was higher in species resident on both continents and African residents than in migrants and Eurasian residents. <em>Haemoproteus</em> prevalence was lower in Eurasian residents than species resident on both continents. Our findings contrast with previous findings in the North-South American flyway, where long-distance migrants had higher parasite diversity than residents and short-distance migrants, although we found contrasting patterns for parasite diversity to those seen for parasite prevalence. Crucially, our results suggest that geographic range may be more important than migratory strategy in driving parasite diversity within species along the African-Palaearctic flyway. Our findings differ between the three parasite genera included in our analysis, suggesting that vector ecology may be important in determining these large-scale patterns. Our results add to our understanding of global patterns in parasite diversity and abundance, and highlight the need to better understand the influence of vector ecology to understand the drivers of infection risk and predict responses to environmental change.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 14","pages":"Pages 787-796"},"PeriodicalIF":4.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0020751923001522/pdfft?md5=4502f760ce88a522366f6dba7589111b&pid=1-s2.0-S0020751923001522-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9924348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interrelationships and properties of parasite aggregation measures: a user’s guide","authors":"A. Morrill ,&nbsp;R. Poulin ,&nbsp;M.R. Forbes","doi":"10.1016/j.ijpara.2023.06.004","DOIUrl":"10.1016/j.ijpara.2023.06.004","url":null,"abstract":"<div><p>Aggregation of macroparasites among hosts is nearly universal among parasite-host associations. Researchers testing hypotheses on origins of parasite aggregation and its importance to parasite and host population ecology have used different measures of aggregation that are not necessarily measuring the same thing, potentially clouding our understanding of underlying epidemiological processes. We highlight these differences in meanings by exploring properties and interrelationships of six common measures of parasite aggregation, and provide a “user’s guide” to inform researchers’ decisions regarding their application. We compared the mathematical expressions of the different measures of aggregation, and ran two series of simulations and analyses. The first simulations tested the effect of random removals of parasites on aggregation levels under different conditions, while the second explored interrelationships between the measures, as well as between other individual parasitological sample measures (i.e. mean abundance, prevalence) and aggregation. Results of simulations and analyses showed that the six measures of aggregation could be separated readily into three groups: the variance-to-mean ratio (VMR) together with mean crowding, patchiness with <em>k</em> of the negative binomial, and Poulin’s <em>D</em> with Hoover’s index. These three pairs of measures showed differing responses to random parasite removals and differing relations with mean abundance and/or prevalence, highlighting that metrics capture different variation in other sample measures and different attributes of aggregation. We used results of our simulations and analyses, and a literature review, to list the properties, advantages, and disadvantages of each aggregation metric. We provide a comprehensive exploration of what is assessed by each metric, as a guide to metric choice. We implore researchers to provide enough information such that aggregation measures from each group are reported or can be readily calculated. Such steps are needed to allow large-scale analyses of variation in degrees of aggregation within and among parasite-host associations, to uncover epidemiological processes shaping parasite distributions.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 14","pages":"Pages 763-776"},"PeriodicalIF":4.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10234070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ticks (Acari: Ixodida) on synanthropic small and medium-sized mammals in areas of the northeastern United States infested with the Asian longhorned tick, Haemaphysalis longicornis","authors":"Francisco C. Ferreira ,&nbsp;Julia González ,&nbsp;Matthew T. Milholland ,&nbsp;Grayson A. Tung ,&nbsp;Dina M. Fonseca","doi":"10.1016/j.ijpara.2023.06.003","DOIUrl":"10.1016/j.ijpara.2023.06.003","url":null,"abstract":"<div><p>The northeastern United States (US) is a hotspot for tick-borne diseases. Adding to an already complex vector landscape, in 2017 large populations of the invasive <em>Haemaphysalis longicornis</em>, the Asian longhorned tick, were detected in New Jersey (NJ) and later found to be widespread from Connecticut to Georgia<em>.</em> In its native range in northeastern Asia, <em>H. longicornis</em> is considered an important vector of deadly pathogens to humans, companion animals, and livestock. To identify the primary hosts of <em>H. longicornis,</em> we surveyed synanthropic small and medium-sized mammals in three different sites in suburban New Brunswick, NJ. Specifically, we collected approximately 9,000 tick specimens belonging to nine species from 11 different species of mammals sampled between May and September 2021. We found that <em>H. longicornis</em> feeds more frequently on rodents than previously thought, and that this invasive tick is likely exposed to important enzootic and zoonotic pathogens. Overall, we obtained detailed information about the seasonal dynamics and feeding patterns of six tick species common in the northeastern US, <em>Haemaphysalis longicornis</em>, <em>Amblyomma americanum, Dermacentor variabilis, Ixodes scapularis, Ixodes texanus</em> and <em>Ixodes cookei</em>. We found that unlike <em>I. scapularis</em> that feeds on mammals of all sizes, <em>H. longicornis</em> feeds on hosts following the general pattern of <em>A. americanum</em>, favoring larger species such as skunks, groundhogs, and raccoons. However, our survey revealed that unlike <em>A. americanum</em>, <em>H. longicornis</em> reaches high densities on Virginia opossum. Overall, the newly invasive <em>H. longicornis</em> was the most numerous tick species, both on multiple host species and in the environment, raising significant questions regarding its role in the epidemiology of tick-borne pathogens, especially those affecting livestock, companion animals and wildlife. In conclusion, our findings provide valuable insights into the tick species composition on mammalian hosts in NJ and the ongoing national expansion of <em>H. longicornis</em>.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 14","pages":"Pages 809-819"},"PeriodicalIF":4.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10234071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linking avian malaria parasitemia estimates from quantitative PCR and microscopy reveals new infection patterns in Hawai'i","authors":"Christa M. Seidl ,&nbsp;Francisco C. Ferreira ,&nbsp;Katy L. Parise ,&nbsp;Kristina L. Paxton ,&nbsp;Eben H. Paxton ,&nbsp;Carter T. Atkinson ,&nbsp;Robert C. Fleischer ,&nbsp;Jeffrey T. Foster ,&nbsp;A. Marm Kilpatrick","doi":"10.1016/j.ijpara.2023.10.001","DOIUrl":"10.1016/j.ijpara.2023.10.001","url":null,"abstract":"<div><p><em>Plasmodium</em> parasites infect thousands of species and provide an exceptional system for studying host-pathogen dynamics, especially for multi-host pathogens. However, understanding these interactions requires an accurate assay of infection. Assessing <em>Plasmodium</em> infections using microscopy on blood smears often misses infections with low parasitemias (the fractions of cells infected), and biases in malaria prevalence estimates will differ among hosts that differ in mean parasitemias. We examined <em>Plasmodium relictum</em> infection and parasitemia using both microscopy of blood smears and quantitative polymerase chain reaction (qPCR) on 299 samples from multiple bird species in Hawai'i and fit models to predict parasitemias from qPCR cycle threshold (Ct) values. We used these models to quantify the extent to which microscopy underestimated infection prevalence and to more accurately estimate infection patterns for each species for a large historical study done by microscopy. We found that most qPCR-positive wild-caught birds in Hawaii had low parasitemias (Ct scores ≥35), which were rarely detected by microscopy. The fraction of infections missed by microscopy differed substantially among eight species due to differences in species’ parasitemia levels. Infection prevalence was likely 4–5-fold higher than previous microscopy estimates for three introduced species, including <em>Zosterops japonicus</em>, Hawaii’s most abundant forest bird, which had low average parasitemias. In contrast, prevalence was likely only 1.5–2.3-fold higher than previous estimates for <em>Himatione sanguinea</em> and <em>Chlorodrepanis virens</em>, two native species with high average parasitemias. Our results indicate that relative patterns of infection among species differ substantially from those observed in previous microscopy studies, and that differences depend on variation in parasitemias among species. Although microscopy of blood smears is useful for estimating the frequency of different <em>Plasmodium</em> stages and host attributes, more sensitive quantitative methods, including qPCR, are needed to accurately estimate and compare infection prevalence among host species.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 2","pages":"Pages 123-130"},"PeriodicalIF":4.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71481202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"microRNA silencing in a whole worm cestode model provides insight into miR-71 function","authors":"Andrés Grecco ,&nbsp;Natalia Macchiaroli ,&nbsp;Matías Gastón Pérez ,&nbsp;Adriano Casulli ,&nbsp;Marcela Alejandra Cucher ,&nbsp;Mara Cecilia Rosenzvit","doi":"10.1016/j.ijpara.2023.08.002","DOIUrl":"10.1016/j.ijpara.2023.08.002","url":null,"abstract":"<div><p>Parasites belonging to the class Cestoda include zoonotic species such as <em>Echinococcus</em> spp. and <em>Taenia</em> spp. that cause morbidity and mortality in endemic areas, mainly affecting pastoral and rural communities in low income countries but also upper middle income countries. Cestodes show remarkable developmental plasticity, implying tight regulation of gene expression throughout their complex life cycles. Despite the recent availability of genomic data for cestodes, little progress was made on postgenomic functional studies. MicroRNAs (miRNAs) are key components of gene regulatory systems that guide diverse developmental processes in multicellular organisms. miR-71 is a highly expressed miRNA in cestodes, which is absent in vertebrates and targets essential parasite genes, representing a potential key player in understanding the role of miRNAs in cestodes biology. Here we used transfection with antisense oligonucleotides to perform whole worm miRNA knockdown in tetrathyridia of <em>Mesocestoides vogae</em> (<em>syn. Mesocestoides corti)</em>, a laboratory model of cestodes. We believe this is the first report of miRNA knockdown at the organism level in these parasites. Our results showed that <em>M. vogae</em> miR-71 is involved in the control of strobilation in vitro and in the establishment of murine infection. In addition, we identified miR-71 targets in <em>M. vogae</em>, several of them being de-repressed upon miR-71 knockdown. This study provides new knowledge on gene expression regulation in cestodes and suggests that miRNAs could be evaluated as new selective therapeutic targets for treating Neglected Tropical Diseases prioritised by the World Health Organization.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 13","pages":"Pages 699-710"},"PeriodicalIF":4.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10224658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is vision deterioration responsible for changes in the host’s behavior caused by eye flukes?","authors":"Mikhail Gopko ,&nbsp;Darya Tkachenko ,&nbsp;Anastasia Shpagina ,&nbsp;Darya Maximenko ,&nbsp;Ekaterina Mironova","doi":"10.1016/j.ijpara.2023.06.001","DOIUrl":"10.1016/j.ijpara.2023.06.001","url":null,"abstract":"<div><p>Trematodes localizing in the lenses of fish change the behavior of their hosts. These behavioral changes are widely suggested to be parasitic manipulations of host behavior aimed at increasing the possibility of eye flukes completing their life cycle. It is often assumed that fish change their behavior due to the vision deterioration caused by trematode larvae. We checked this assumption by testing <em>Salvelinus malma</em> infected with eye flukes (<em>Diplostomum pseudospathaceum</em>) under different lighting conditions. We suggested that if the parasite alters the host’s behavior through vision impairment, then in the dark (when fish do not rely on vision to navigate), the difference in the behavior of infected and uninfected fish would disappear. Eye flukes, indeed, changed fish behavior, making their hosts less vigilant. We believe this is the first evidence of possible parasitic manipulation in this study system. However, contrary to expectations, the difference in the behavior of infected and control fish was independent of the lighting conditions. Our results suggest that mechanisms of behavioral change other than vision impairment should be taken into account in this fish-eye fluke study system.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 13","pages":"Pages 731-738"},"PeriodicalIF":4.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10193696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sharing is caring? Barcoding suggests co-introduction of dactylogyrid monogeneans with Nile tilapia and transfer towards native tilapias in sub-Saharan Africa","authors":"Mare Geraerts ,&nbsp;Tine Huyse ,&nbsp;Maxwell Barson ,&nbsp;Hassan Bassirou ,&nbsp;Charles F. Bilong Bilong ,&nbsp;Arnold R. Bitja Nyom ,&nbsp;Auguste Chocha Manda ,&nbsp;Armando J. Cruz-Laufer ,&nbsp;Clément Kalombo Kabalika ,&nbsp;Gyrhaiss Kapepula Kasembele ,&nbsp;Fidel Muterezi Bukinga ,&nbsp;Samuel Njom ,&nbsp;Maarten Van Steenberge ,&nbsp;Tom Artois ,&nbsp;Maarten P.M. Vanhove","doi":"10.1016/j.ijpara.2023.05.007","DOIUrl":"10.1016/j.ijpara.2023.05.007","url":null,"abstract":"<div><p>Invasive Nile tilapias negatively impact native tilapia species through hybridisation and competition. However, the co-introduction of parasites with Nile tilapia, and subsequent changes in parasite communities, are scarcely documented. Monogeneans are known pathogens of cultured Nile tilapia, although little is known about their fate once Nile tilapias establish in new ecosystems. We investigate the parasitological consequences of Nile tilapia introduction on native tilapias in basins in Cameroon, the Democratic Republic of the Congo (DRC), and Zimbabwe, focusing on ectoparasitic dactylogyrids (Monogenea). Using the mitochondrial cytochrome oxidase <em>c</em> subunit I (<em>COI</em>) and nuclear 18S-internal transcribed spacer 1 (18S-ITS1) rDNA region of 128 and 166 worms, respectively, we evaluated transmission of several dactylogyrid species. Parasite spillover from Nile tilapia was detected for <em>Cichlidogyrus tilapiae</em> to <em>Coptodon guineensis</em> in Cameroon, <em>Cichlidogyrus thurstonae</em> to <em>Oreochromis macrochir</em> in the DRC, and <em>Cichlidogyrus halli</em> and <em>C. tilapiae</em> to <em>Coptodon rendalli</em> in Zimbabwe. Parasite spillback to Nile tilapia was detected for <em>Cichlidogyrus papernastrema</em> and <em>Scutogyrus gravivaginus</em> from <em>Tilapia sparrmanii</em> and <em>Cichlidogyrus dossoui</em> from <em>C. rendalli</em> or <em>T. sparrmanii</em> in the DRC, and <em>Cichlidogyrus chloeae</em> from <em>Oreochromis</em> cf. <em>mortimeri</em> and <em>S. gravivaginus</em> from <em>O. macrochir</em> in Zimbabwe. ‘Hidden’ transmissions (i.e. transmission of certain parasite lineages of species that are naturally present on both alien and native hosts) were detected for <em>C. tilapiae</em> and <em>Scutogyrus longicornis</em> between Nile tilapia and <em>Oreochromis aureus</em> and <em>C. tilapiae</em> between Nile tilapia and <em>Oreochromis mweruensis</em> in the DRC, and <em>Cichlidogyrus sclerosus</em> and <em>C. tilapiae</em> between Nile tilapia and <em>O.</em> cf. <em>mortimeri</em> in Zimbabwe. A high density of Nile tilapia occurring together with native tilapias, and the broad host range and/or environmental tolerance of the transmitted parasites, are proposed as factors behind parasite transmission through ecological fitting. However, continuous monitoring and the inclusion of environmental variables are necessary to understand the long-term consequences of these transmissions on native tilapias and to elucidate other underlying factors influencing these transmissions.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 13","pages":"Pages 711-730"},"PeriodicalIF":4.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9854115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abomasal RNA-seq reveals a strong local cellular response in suckling lambs with resistance against Haemonchus contortus","authors":"José Gabriel Gonçalves Lins ,&nbsp;Ana Cláudia Alexandre de Albuquerque ,&nbsp;Fabiana Alves de Almeida ,&nbsp;Collette Britton ,&nbsp;Camila Malossi ,&nbsp;João Pessoa de Araújo-Júnior ,&nbsp;Helder Louvandini ,&nbsp;Alessandro F.T. Amarante","doi":"10.1016/j.ijpara.2023.06.008","DOIUrl":"10.1016/j.ijpara.2023.06.008","url":null,"abstract":"<div><p>Santa Ines (SI) and Ile de France (IF) sheep are known to be resistant and susceptible to <em>Haemonchus contortus</em> infection, respectively. Several studies have shown some genes as potential biological markers for sheep resistance against gastrointestinal nematodes using molecular tools, including transcriptomic analysis. In this study, we sequenced the polyadenylated RNA of the abomasal tissue of SI and IF suckling lambs to identify mucosa-specific transcript alterations between breeds artificially infected with <em>H. contortus</em>. Naïve SI (<em>n</em> = 4) and IF (<em>n</em> = 4) lambs were artificially infected every other day, over a period of 52 days, from 14 to 66 days old, with a total of 5,400 <em>H. contortus</em> infective larvae. Fundic abomasal tissue samples were collected at 68 days old, and submitted to high-throughput RNA sequencing (RNA-seq). Differential expression analysis (<em>P</em> value &lt; 0.001 and False Discovery Rate (FDR) &lt; 0.05) between SI and IF samples identified 292 genes, most of which showed greater expression in SI lambs. To help annotate and assign possible function to differentially expressed genes (DEGs), we used previously available single-cell RNA-seq (scRNA-seq) data from ovine abomasal mucosa to putatively identify cell types and possible mechanisms involved in resistance to <em>H. contortus</em>. In particular, genes associated with endothelial and tuft cells showed the greatest increases in expression in SI relative to IF lambs. SI lambs had higher percentages of tuft cells than IF lambs in the fundic abomasal mucosa. Although we found innate immunity (cell-mediated in mucosa) acting as a protagonist in impairing <em>H. contortus</em> infection, a stronger acquired immune response was being modulated at an earlier stage by SI lambs. We suggest that the complex connection between innate and adaptive immunity is via cellular antigen processing and presentation (APP). Based on comparison with scRNA-seq data, SI lambs showed a robust APP mechanism characterized mainly by greater T cell APP, macrophage differentiation, and cytokine signalling. We identified potential mechanisms and markers to advance knowledge for selection of <em>H. contortus</em> resistance at a very early age, in SI as well as in other commercial sheep breeds.</p></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"53 13","pages":"Pages 739-749"},"PeriodicalIF":4.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10237601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}