Differences In Parasite Prevalence Research Articles

Evolutionary drivers of sex-specific parasite prevalence in wild birds.

Males and females often differ in ecology, behaviour and lifestyle, and these differences are expected to lead to sex differences in parasite susceptibility. However, neither the sex differences in parasite prevalence, nor their ecological and evolutionary drivers have been investigated across a broad range of taxa using phylogenetically corrected analyses. Using the most extensive dataset yet that includes 755 prevalence estimates from 151 wild bird species in a meta-analytic framework, here we compare sex differences in blood and gastrointestinal parasites. We show that despite sex differences in parasite infection being frequently reported in the literature, only Haemoproteus infections were more prevalent in females than in males. Notably, only seasonality was strongly associated with the sex-specific parasite prevalence of both Leucocytozoon and Haemoproteus, where birds showed greater female bias in prevalence during breeding periods compared to the non-breeding period. No other ecological or sexual selection variables were associated with sex-specific prevalence of parasite prevalence. We suggest that much of the variation in sex-biased prevalence could be idiosyncratic, and driven by local ecology and behavioural differences of the parasite and the host. Therefore, breeding ecology and sexual selection may only have a modest influence on sex-different parasite prevalence across wild birds.

Parasite airlines: mapping the distribution and transmission of avian blood parasites in migratory birds

During their journeys, migratory birds encounter a wider range of parasites than residents, transporting them over vast distances. While some parasites are widely distributed, transmission is not inevitable and depends on the presence of competent arthropod vectors as well as parasite compatibility with native bird species. Distinguishing between parasite distribution and transmission areas is crucial for monitoring and assessing risks to native bird species, as distribution areas, with the appropriate conditions, could become potential transmission areas. In this study, blood samples from 455 reed-living birds of the genera Acrocephalus, Locustella, and Emberiza, collected in the nature reserve “Die Reit” in Hamburg, Germany were screened, targeting haemosporidian parasites, trypanosomes, and filarioid nematodes. Determination of migratory bird age was employed to ascertain the transmission area of the detected parasites. Transmission areas were determined, based on information provided by resident and juvenile birds as well as findings in competent vectors. Long-distance migratory birds of the genus Acrocephalus showed a higher prevalence and diversity of blood parasites compared with partially migratory birds such as Emberiza schoeniclus. Notably, an age-dependent difference in parasite prevalence was observed in Acrocephalus spp., but not in E. schoeniclus. Nematodes were absent in all examined bird species. Proposed transmission areas were identified for nine haemosporidian lineages, showing three different types of transmission area, either with limited transmission in Europe or Africa, or active transmission in both regions.

Sympatry in a nightingale contact zone has no effect on host-specific blood parasite prevalence and lineage diversity

Parasites are a key driving force behind many ecological and evolutionary processes. Prevalence and diversity of parasites, as well as their effects on hosts, are not uniform across host species. As such, the potential parasite spillover between species can significantly influence outcomes of interspecific interactions. We screened two species of Luscinia nightingales for haemosporidian blood parasites (Plasmodium, Leucocytozoon and Haemoproteus) along an approximately 3000 km transect in Europe, incorporating areas of host distant allopatry, close allopatry and sympatry. We found significant differences in infection rates between the two host species, with common nightingales having much lower parasite prevalence than thrush nightingales (36.7% versus 83.8%). This disparity was mostly driven by Haemoproteus prevalence, which was significantly higher in thrush nightingales while common nightingales had a small, but significantly higher, Plasmodium prevalence. Furthermore, we found no effect of proximity to the contact zone on infection rate in either host species. Despite having lower infection prevalence, common nightingales were infected with a significantly higher diversity of parasite lineages than thrush nightingales, and lineage assemblages differed considerably between the two species, even in sympatry. This pattern was mostly driven by the large diversity of comparatively rare lineages, while the most abundant lineages were shared between the two host species. This suggests that, despite the close evolutionary relationships between the two nightingales, there are significant differences in parasite prevalence and diversity, regardless of the distance from the contact zone. This suggests that spillover of haemosporidian blood parasites is unlikely to contribute towards interspecific interactions in this system.

Avian Plasmodium in invasive and native mosquitoes from southern Spain

BackgroundThe emergence of diseases of public health concern is enhanced by factors associated with global change, such as the introduction of invasive species. The Asian tiger mosquito (Aedes albopictus), considered a competent vector of different viruses and parasites, has been successfully introduced into Europe in recent decades. Molecular screening of parasites in mosquitoes (i.e. molecular xenomonitoring) is essential to understand the potential role of different native and invasive mosquito species in the local circulation of vector-borne parasites affecting both humans and wildlife.MethodsThe presence of avian Plasmodium parasites was molecularly tested in mosquitoes trapped in five localities with different environmental characteristics in southern Spain from May to November 2022. The species analyzed included the native Culex pipiens and Culiseta longiareolata and the invasive Ae. albopictus.ResultsAvian Plasmodium DNA was only found in Cx. pipiens with 31 positive out of 165 mosquito pools tested. None of the Ae. albopictus or Cs. longiareolata pools were positive for avian malaria parasites. Overall, eight Plasmodium lineages were identified, including a new lineage described here. No significant differences in parasite prevalence were found between localities or sampling sessions.ConclusionsUnlike the invasive Ae. albopictus, Cx. pipiens plays a key role in the transmission of avian Plasmodium in southern Spain. However, due to the recent establishment of Ae. albopictus in the area, further research on the role of this species in the local transmission of vector-borne pathogens with different reservoirs is required.Graphical

Effects of Season, Habitat, and Host Characteristics on Ectoparasites of Wild Rodents in a Mosaic Rural Landscape.

Despite the large number of studies on rodent ectoparasites-most of them vectors of epidemiologically important pathogens-infestation patterns remain poorly understood in various ecological contexts, such as the highly patchy agricultural landscapes. We aimed to relate the infestation of rodents to temporal, habitat, and host variables. We assessed the difference in parasite prevalence and mean abundance depending on host sex, age, and body weight, season, and land use intensity. Furthermore, we analysed the effect of host species abundance and the differential responses of parasites in main and minor host species. The field survey was conducted in a rural landscape in southern Transylvania (Romania) between June and September 2010-2011. We live-trapped small mammals, collected the ticks and fleas, and recorded the presence of lice and mites. Overall, we found the same infestation patterns largely reported in the literature: higher prevalence and mean abundance in heavier adult males, significant seasonality and differences among host species, and evidence of the dilution effect. The uniqueness of our study system was the negative effect of the land use intensity on the prevalence and mean abundance of parasites, explained by the highly patchy mosaic landscape.

Non-MHC immunity genes do not affect parasite load in European invasive populations of common raccoon

Understanding the evolutionary mechanisms behind invasion success enables predicting which alien species and populations are the most predisposed to become invasive. Parasites may mediate the success of biological invasions through their effect on host fitness. The evolution of increased competitive ability (EICA) hypothesis assumes that escape from parasites during the invasion process allows introduced species to decrease investment in immunity and allocate resources to dispersal and reproduction. Consequently, the selective pressure of parasites on host species in the invasive range should be relaxed. We used the case of the raccoon Procyon lotor invasion in Europe to investigate the effect of gastrointestinal pathogen pressure on non-MHC immune genetic diversity of newly established invasive populations. Despite distinct differences in parasite prevalence between analysed populations, we detected only marginal associations between two analysed SNPs and infection intensity. We argue that the differences in parasite prevalence are better explained by detected earlier associations with specific MHC-DRB alleles. While the escape from native parasites seems to allow decreased investment in overall immunity, which relaxes selective pressure imposed on immune genes, a wide range of MHC variants maintained in the invasive range may protect from newly encountered parasites.

Prevalence of Gastrointestinal Parasites in Domestic Chickens (Gallus gallus domestica) Slaughtered in Abattoir of Macks Farm Osara, Kogi State

This study was conducted to determine the prevalence of gastrointestinal parasites in domestic chickens using the abattoir of Mack's farm Osara, Kogi state between January and March 2022. A total of 200 (100 exotic and 100 local breeds with 50 males and 50 females each) faecal samples from the gastro-intestinal tracts of already slaughtered chicken were examined from January to March 2022 using formol-ether concentration technique for the presence of gastrointestinal parasites. Microscopic method was employed for morphological identification of parasite isolates. The result showed that of the 200 samples examined, 178 (89%) were found to be infected with one or more parasites. A higher infection rate of 90 (90%) was found in the local breed than in exotic breed 88(88%). The helminths species found were, Ascaridia galli 66(33.67%), Heterakis gallinarum 44(22.44%), Capillaria Spp 30(15.30%), Gongylonema ingluvocola 20(10.20%), Strongyloides avium 6(3.06%), Raillietina echinobrothrida 6(3.06%), Tricuris tricura 10(5.10%), Choanotaenia infundibulum 10(5.10%) and Coccidian spp 4(2.04%) while the gastrointestinal protozoan isolated was Coccidian spp 4(2.04%).
 Conclusion: An insignificant difference in parasite prevalence (p >0.05) exists between exotic and local chicken, suggesting potential consumer exposure to infection through cross-infection. This study highlights the risk associated with consuming chicken from poorly managed poultry systems and establishes the need for policymaking toward improved poultry production.

Toxoplasma gondii and related Sarcocystidae parasites in harvested caribou from Nunavik, Canada.

Caribou are keystone species important for human harvest and of conservation concern; even so, much is unknown about the impact of parasites on caribou health and ecology. The aim of this study was to determine the seroprevalence, tissue prevalence, and diversity of tissue-dwelling coccidian parasites (including Toxoplasma gondii, Neospora caninum and Sarcocystis spp.) in 88 migratory caribou (Rangifer tarandus) harvested for human consumption in two communities in Nunavik, Québec, Canada. Both T. gondii and N. caninum have potential to cause abortions and neurological disease in caribou. Seroprevalence for antibodies to T. gondii using ELISA on fluid from thawed hearts was 18% overall, and no DNA of T. gondii was detected in tissues, which has positive implications for food safety since this parasite is zoonotic. Seroprevalence for antibodies to N. caninum using competitive ELISA was 5%, and DNA of N. caninum was detected in only one heart sample. DNA of Sarcocystis, a non-zoonotic, related coccidian, was detected in tissue samples from 85% of caribou, with higher prevalence in heart (82%) than skeletal muscle (47%). This is the first time that Sarcocystis spp. from caribou in Canada have been identified to species level, many of which have been described in reindeer from Fennoscandia. The high prevalence and diversity of Sarcocystis spp. suggests intact trophic relationships between canids and caribou in Nunavik. Besnoitia spp. was serendipitously detected in three muscle samples, a parasite previously associated with skin lesions in caribou in Nunavik. Community-level differences in T. gondii exposure and prevalence of Sarcocystis spp. in skeletal muscle tissues may reflect differences in hunter selection of individual animals and muscles, or possibly regional differences in the ecology of carnivore definitive hosts for these parasites. Further work is needed to explore effects of tissue coccidians in caribou, their taxonomic classifications, and community level differences in parasite prevalence and diversity.

Bird species with wider geographical ranges have higher blood parasite diversity but not prevalence across the African-Eurasian flyway

Avian blood parasites, from the genera Plasmodium, Haemoproteus and Leucocytozoon, 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 Plasmodium, Haemoproteus and Leucocytozoon) 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 (n = 36 species), African only (n = 41), and species resident on both continents (n = 17), alongside intercontinental migrants (n = 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 Plasmodium diversity than all other groups, and both migrants and species resident on both continents had higher Haemoproteus diversity than both African and Eurasian residents. Leucocytozoon diversity did not differ between groups. Prevalence patterns were less clear, with marked differences between genera. Both Plasmodium and Leucocytozoon prevalence was higher in species resident on both continents and African residents than in migrants and Eurasian residents. Haemoproteus 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.

Parasite Prevalence in Feral Swine (Sus scrofa) from the Great Smoky Mountains National Park, USA.

Feral swine (Sus scrofa) are an introduced species to the Great Smoky Mountains National Park (GSMNP), US, and serve as carriers of several diseases that are considered a threat to other wildlife, domestic animals, and humans. During 2013 and 2015, fecal samples from 67 feral swine from the GSMNP within both Tennessee and North Carolina, US, were opportunistically collected as part of a feral swine removal program and submitted to the University of Tennessee College of Veterinary Medicine, Knoxville, Tennessee, for parasite screening by centrifugal sugar flotation. Ten taxa from the phyla Acanthocephala, Apicomplexa, and Nematoda were identified: Ascaris spp., Strongylid-type spp., Capillaria spp., Trichuris suis, Metastrongylus spp., Macracanthorhynchus spp., Coccidia, Sarcocystis spp., and Cryptosporidium spp. In 98.5% of samples, at least one parasite was found. No differences in parasite prevalence or species diversity were noted based on state of collection (Tennessee or North Carolina), sex, or age. The high prevalence of gastrointestinal parasites in these feral swine, some of which are zoonotic, represents a potential public health risk as well as a concern for free-range swine farmers.

Biogeography, climate, and land use create a mosaic of parasite risk in native bumble bees

Host-parasite interactions are crucial to the regulation of host population growth, as they often impact both long-term population stability and ecological functioning. Animal hosts navigate a number of environmental conditions, including local climate, anthropogenic land use, and varying degrees of spatial isolation, all of which can mediate parasitism exposure. Despite this, we know little about the potential for these environmental conditions to impact pathogen prevalence at biogeographic scales, especially for key ecosystem service-providing animals. Bees are essential pollination providers that may be particularly sensitive to biogeography, climate, and land-use as these factors are known to limit bee dispersal and contribute to underlying population genetic variation, which may also impact host-parasite interactions. Importantly, many native bumble bee species have recently shown geographic range contractions, reduced genetic diversity, and increased parasitism rates, highlighting the potential importance of interacting and synergistic stressors. In this study, we incorporate spatially explicit environmental, biogeographic, and land-use data in combination with genetically derived host population data to conduct a large-scale epidemiological assessment of the drivers of pathogen prevalence across >1000 km for a keystone western US pollinator, the bumble bee Bombus vosnesenskii. We found high rates of infection from Crithidia bombi and C. expoekii, which show strong spatial autocorrelation and which were more prevalent in northern latitudes. We also show that land use barriers best explained differences in parasite prevalence and parasite community composition, while precipitation, elevation, and B. vosnesenskii nesting density were important drivers of parasite prevalence. Overall, our results demonstrate that human land use can impact critical host-parasite interactions for native bees at massive spatial scales. Further, our work indicates that disease-related survey and conservation measures should take into account the independent and interacting influences of climate, biogeography, land use, and local population dynamics.

Evaluation of Parasitofauna of Four Economically Important Fish Species (Synodontis Budgetti, Chrysichthys Nigrodigitatus, Bagrus Docmac and Heterobranchus Bidorsalis) From River Okpokwu, Apa, Nigeria

The parasitic fauna of four economically important fish species comprising of Synodontis budgetti, Chrysichthys nigrodigitatus, Bagrus docmac and Heterobranchus bidorsalis from River Okpokwu, Apa, Nigeria, was investigated. A total of 161 fish samples comprising of 57 S. budgetti, 48 C. nigrodigitatus, 24 B. docmac and 32 H. bidorsalis were randomly purchased and subjected to parasitological examination. The overall parasite prevalence of all the fish species was 36.60% out of which S. budgetti, C. nigrodigitatus, B. docmac and H. bidorsalis accounted for 14.30%, 11.20%, 1.90% and 9.30%, respectively. However, the prevalence of infection by each fish species were 40.40%, 37.50%, 12.50% and 46.90% for S. budgetti, C. nigrodigitatus, B. docmac and H. bidorsalis, respectively. There was no significant difference in parasite prevalence for fish species (p>0.05) though, S. budgetti had the highest prevalence of infection (14.70%) with B. docmac recording the least (1.90%). Also, while the highest prevalence of infection was recorded for nematode (17.40%), the least (3.70%) each was recorded for trematode and copepode, respectively. Of the parasitic taxa, nematode was the most abundant (56.50%) and had the highest prevalence (17.40%). The parasites recovered from the fish species belonged to a species of acanthocephala (Neoechinorhynchus rutili), copepode (Argulus africanus.) trematode (Clinostomum complanatum), 2 species of cestode (Ligula intestinalis and Diphillobothrium latum) and 4 species of nematode (Capillaria philippinensis, Eustrongylides tubifex, Camallanus polypteri and Procamallanus laevionchus). Out of the total number (292) of parasites recovered from the infested body parts of the fish, intestine had the highest percentage parasite load (62.30%) and prevalence (29.80) while the gill had the least 16(5.50%) parasite load and prevalence of 3.10. Generally, the prevalence of parasites (43.00%), percentage parasite recovered (56.50%), mean abundance (2.60) and mean intensity (5.90) were higher for the female fish samples compared to the males with the prevalence of parasites, percentage parasite recovered, mean abundance and mean intensity of (32.00%), (43.50%), (1.30) and (4.10), respectively. However, there was no significant difference (p>0.05) by sex in the prevalence of parasites of all the fish species. The size class related prevalence showed an increase in parasitic infections (24.60%) and (20.80%) in S. budgetti and C. nigrodigitatus) in the length groups of 13.00 to 15.90cm and 19.00 to 22.90cm while the least (5.30%) and (6.30%) were recorded for S. budgetti and C. nigrodigitatus in the length groups of 10.00 to 12.90cm and 15.00 to 18.90cm, respectively. However, while the highest prevalence (8.30%) and (21.90%) were recorded for smaller samples of B. docmac and H. bidorsalis in the length groups of 10.00 to 20.90cm and 13.00 – 21.90cm, the least (4.20%) and (3.10%) were recorded in length groups of 41.00 to 50.90cm and 39.00 – 54.90cm for bigger samples of B. docmac and H. bidorsalis, respectively. Keywords: Parasitofauna, River Okpokwu, Prevalence, Nematode, Sex

Sexual and developmental variations of ecto-parasitism in damselflies.

The prevalence and intensity of parasitism can have different fitness costs between sexes, and across species and developmental stages. This variation could arise because of species specific sexual and developmental differences in body condition, immunity, and resistance. Theory predicts that the prevalence of parasitism will be greater in individuals with poor body condition and the intensity of parasitism will be greater in individuals with larger body size. These predictions have been tested and verified in vertebrates. In insects, however, contradictory evidence has been found in different taxa. Here, we tested these predictions on two species of Agriocnemis (Agriocnemis femina and Agriocnemis pygmaea) damselflies, which are parasitized by Arrenurus water mite ectoparasites. We measured body weight, total body length, abdomen area and thorax area of non-parasitized damselflies and found body condition varied between males and females, between immature females and mature females and between A. femina and A. pygmaea. Then, we calculated the parasite prevalence, i.e., the absence or presence of parasites and intensity, i.e., the number of parasites per infected damselfly in eleven natural populations of both species. In line to our predictions, we observed greater prevalence in immature females than mature females but found no difference in parasite prevalence between males and females. Furthermore, we found that parasite intensity was higher in females than males and in immature females than mature females. Our result also showed that the frequency and intensity of parasitism varied between the two studied species, being higher in A. pygmaea than A. femina. Our study provides evidence that parasitism impacts sexes, developmental stages and species differentially and suggests that variation may occur due to sex, developmental stage, and species-specific resistance and tolerance mechanism.

Gastrointestinal parasites of Leontopithecus chrysomelas in the Atlantic Forest, Brazil.

We performed coproparasitological testing of free-living golden-headed lion tamarins, Leontopithecus chrysomelas, using the Hoffmann-Pons-Janner method. In total, we collected 118 samples from ten groups: four living in Federal Protected Area and six living in Non-Protected Areas of cocoa farms. Eggs from parasites of the Acanthocephala phylum and Spiruridae, Ancylostomatidae, Ascarididae and Oxyuridae families were identified, as well as the genus Strongyloides (Nematode: Strongyloididae) and phylum Apicomplexa. This is the first description of infection with coccidian, Trichuridae family and Strongyloides spp. in L. chrysomelas. A total of 48% (n= 57) of the animals were infected and the highest prevalence (37.2±SD 8.72, n = 44) was for Acanthocephalidae, followed by Spiruridae (8.5±SD 5.03, n = 10). There was no difference in parasite prevalence by age classes or sex. However, we found higher diversity and prevalence of parasites in animals living in the Federal Protected Area. These results suggest that intestinal parasites may be influenced by environmental factors, such as the management of the areas where the animals live, in addition to the feeding behavior of L. chrysomelas and distinct transmission strategies of parasites. The combination of ecological and demographic data combined with parasitological studies may contribute to conservation programs for this species.

Host and geographic differences in prevalence and diversity of gastrointestinal helminths of foxes (Vulpes vulpes), coyotes (Canis latrans) and wolves (Canis lupus) in Québec, Canada.

Wild canids are hosts to a wide range of parasites and can play a role in transmission of zoonoses. As many parasites are transmitted through food webs, and wild canids are at high trophic levels, parasite prevalence and diversity in wild canids can serve as excellent indicators of ecosystem health. Our main objectives were to update knowledge on the composition of gastrointestinal helminths in wild canids from Québec, Canada, and to describe differences in parasite prevalence and diversity among canid species and regions. Hunters and trappers provided whole carcasses of red foxes (Vulpes vulpes) (N = 176), and intestinal tracts of coyotes (Canis latrans) (N = 77) and gray wolves (Canis lupus) (N = 23) harvested for non-research purposes over the winter of 2016–2017. A modified Stoll's centrifugation sucrose flotation on feces of 250 wild canids was used, and eggs of one family and eight genera of parasitic helminths were recovered: diphyllobothriids, Taenia/Echinococcus spp., Capillaria spp., Toxascaris sp., Toxocara sp., Trichuris sp., Uncinaria sp., and Metorchis sp. Adult Taenia spp. cestodes were recovered from 61 of 276 (22%) canids. Six different species (T. hydatigena, T. twitchelli, T. crassiceps, T. polyacantha, T. krabbei, and T. pisiformis-“like”) were differentiated based on DNA sequenced from 65 individual adult cestodes using primers for the nicotinamide adenosine dinucleotide dehydrogenase subunit 1 (ND1) and cytochrome c oxidase subunit 1 (CO1) mitochondrial DNA loci. Alaria sp. trematodes infected 89 of 276 canids (32%). A subset were identified as A. americana at the CO1 locus. The marine trematode Cryptocotyle lingua was reported for the first time in foxes in the province of Québec. These results help us understand more fully the predator-prey relationships within this group of canids. This baseline data in regional parasite prevalence and intensity is critical in order to detect future changes following ecological disturbances due to climate and landscape alterations.

First records of prevalence and diversity of avian haemosporidia in snipe species (genus Gallinago) of Japan.

Migratory birds are important carriers of pathogens such as viruses, bacteria and protozoa. Avian haemosporidia have been detected from many wild birds of Japan, but the infection status of migratory birds and transmission area are still largely unknown. Gallinago snipes are long-distance migratory shorebirds, and five species migrate to or through Japan, including Latham's snipe which is near threatened. Haemosporidian parasites in four snipe species were investigated to understand the role of migratory birds in the transmission of avian haemosporidia. Namely, this study aimed: i) to investigate differences in parasite prevalence and related factors explaining infection likelihood among these migratory species, ii) to explore the diversity in haemosporidian lineages and possible transmission areas, and iii) to assess the possibility of morphological effects of infection. Blood samples were collected from snipes caught in central and southwest Japan during migration. Parasites cytb gene DNA were detected via PCR-based testing, and detected lineages were phylogenetically analyzed. Additionally, factors related to prevalence and morphological effects of infection were statistically tested. 383 birds from four Gallinago snipe species were caught, showing higher overall prevalence of avian haemosporidia (17.8 %) than reported in other wader species in previous studies. This high infection rate is presumably due to increased contact with vector insects, resultant of environmental preferences. The prevalence of Plasmodium spp. Was higher in Swinhoe's snipes, while Haemoproteus spp. Was higher in Latham's snipes. These differences are thought to be related to ecological factors including habitat use, distribution and migratory route. Six lineages detected from juveniles indicate transmission between the breeding and sampling area. Contrary to expectations, a direct link between morphological features and haemosporidian parasite infection were not detected. These findings provide valuable information for conservation of this endangered migratory bird group. Further studies linking biological and parasitological research are anticipated to contribute to conservational actions.

Prevalence of intestinal parasites among Sarki ethnic group of Pala Rural Municipality, Baglung, Nepal.

Intestinal parasitic infections are among the major public and socioeconomic concerns that have adversely affected the well-being of the poor in developing countries. This research work aimed to inspect the prevalence of gastro-intestinal (GI) among Sarki ethnic group of Pala Rural Municipality, Baglung, Nepal. Total 498 stool samples collected in dry, screw capped clean plastic vails and studied for the presence of parasites using direct smear method as well as by concentration method. Overall parasite positive rate was found to be 31.32% (156/498). The prevalence of single infection was higher than double infection among Sarki ethnic group. There were no significant differences in prevalence of parasites among different age-groups, sexes and villages. Positive rate was considerably higher in females (47.5%; 38/80) compared with males (32.5%; 26/80) (P<0.05). Altogether six genera of parasites were encountered. Of them, Trichuris trichura (53.20%; 264/498) was the most prevalent parasite followed by Ascaris lumbricoides (33.97%; 169/498), Entamoeba coli (4.49%; 22/498), Taenia sp. (3.21%; 16/498), Strongyloides stercoralis (2.56%; 13/498) and Hymenolepis nana (2.56%; 13/498). Remarkable prevalence of intestinal parasitic infection was indicated by the present study carried out among Sarki ethnic group of Pala Rural Municipality, Baglung district of Nepal.

Gastrointestinal Strongyles Egg Excretion in Relation to Age, Gender, and Management of Horses in Italy.

Current equine helminth control strategies play a key role in strongyle epidemiology and anthelmintic resistance and have led to the recommendation for new treatment plans, which include diagnostic and efficacy surveillance. Assessing the equine strongyle distribution patterns would thus be useful and this study describes the strongyle prevalence in the equine population in Italy through coprological analysis and coproculture. In addition, individual data on each animal were collected in order to identify risk factors associated with strongyle egg shedding. Of the total number of stables investigated, 86.4% were found to have at least one positive animal and a 39.5% prevalence of strongyle egg shedding with a mean eggs per gram (EPG) of 245. A total of 80% of the total recorded EPG was shed from 12.8% of positive horses, thus confirming the need for new targeted intervention strategies. Significant differences in parasite prevalence were found based on season, sex, geographical distribution, management and rearing system, and breed. Significantly lower EPG values were found in horses that had received anthelmintic treatment, and macrocyclic lactones (MLs) were the most effective. Lastly, although large strongyles are more pathogenic, horses in Italy are mainly burdened by small strongyles, which pose an important animal health risk requiring continuous parasitological monitoring.

Infections by the trematode Microphallus nicolli and the acanthocephalan Profilicollis altmani in relation to the reproductive condition of their intermediate host, the Pacific mole crab Emerita analoga

Abstract Parasites can dramatically influence fecundity of their hosts, so for any host species it is important to establish whether parasite infections affect host reproduction. The Pacific mole crab, Emerita analoga, commonly harbors metacercarial cysts of the trematode Microphallus nicolli and cystacanths of the acanthocephalan Profilicollis altmani. Although these helminths are known to infect primarily larger female mole crabs, they may do so disproportionately when tied to their host’s reproductive condition. This study was undertaken to examine differences in parasite prevalence and abundance between non-ovigerous and ovigerous hosts. Crabs from Del Monte Beach, Monterey, California were collected, carapace length measured, sexed, examined for parasites, and had their reproductive state noted. The vast majority of the crabs sampled were infected with at least one parasite, and over half of the crabs had both M. nicolli and P. altmani. Ovigerous females were significantly larger than non-ovigerous crabs. Prevalence of both trematode metacercarial cysts and acanthocephalan cystacanths was significantly higher in ovigerous females than in non-ovigerous ones. Egg-bearing females were also more heavily infected by both parasites than non-egg-bearing individuals. These results suggest that larger ovigerous crabs may provide greater resources and thus are able to support higher levels of infections. This study shows that neither parasite prevalence nor abundance seemed to affect egg production in E. analoga.

Black spot syndrome in reef fishes: using archival imagery and field surveys to characterize spatial and temporal distribution in the Caribbean

Recently, observations of black spot syndrome (BSS) in Caribbean fishes have been linked to infection by a digenean trematode parasite, Scaphanocephalus expansus. Recently, This study examined the distribution of BSS over multiple spatial and temporal scales: at the island scale in Bonaire, Dutch Caribbean, using field surveys of 4885 fish belonging to three species, and across the wider Caribbean through analysis of 2112 images from Google Images searches (1985–2013). The field surveys in Bonaire indicated that the prevalence (% of individuals affected with BSS) and intensity (severity of BSS measured in 3 stages) were highest in Acanthurus tractus (prevalence 61.8%, including 30.1% in stage 3) followed by Sparisoma aurofrenatum (prevalence 48.3%, 24.1% in stage 3) and lowest in Caranx ruber (prevalence 38.5%, 3.3% in stage 3). Prevalence and intensity of BSS decreased significantly with survey depth (e.g., 2 m: prevalence 68.0%, 22.0% in stage 3; 18 m: prevalence 36.2%, 4.0% in stage 3) and were significantly lower in 2012 than in 2017 (prevalence: 59.3% in 2012, 68.7% in 2017; stage 3: 16.3% in 2012, 25.1% in 2017). The Southeast of Bonaire had significantly lower prevalence of BSS (16.4%) than the other four regions and lower intensity (11.7% in stage 3) than all regions but the Southwest. The Google Images searches querying for ocean surgeonfish, A. tractus and A. bahianus, identified pictures from 26 wider Caribbean locations; BSS was detected in 14 locations of which 13 were new, with the first detection dating back to 1985 in Bonaire. The Southern Caribbean had significantly higher prevalence of BSS (78.1%) than other ecoregions (0–34.6%), and Bonaire was identified as a hotspot, highlighting the utility of mining websites for archival imagery to quantify spatial and temporal patterns in disease phenomena. This study demonstrates how visible signs of parasite infection can be used to find differences in parasite prevalence and loads on a reef, island and sea scale.