Parasite Fauna Research Articles

Parasitic fauna of wild boars (Sus scrofa) from the northwestern region of São Paulo state, Brazil.

In Brazil, the wild boar (Sus scrofa) is the main invasive exotic species, responsible for causing various economic, environmental, and health damages to biodiversity. In view of the above, we aimed in our study to investigate the occurrence of endo and ectoparasites in free-ranging wild boars in the northwest region of the state of São Paulo, Brazil. In total, 45 animals of different sexes and ages were examined in this research. Fecal and urine samples were processed using coproparasitological techniques. Multiple incisions in muscles, liver, and pancreas were also made to investigate cestodes and trematodes, and the entire epidermal region of the animals was analyzed for ectoparasites search. In our study, we demonstrate an occurrence of 97.77% (44/45) and 43.33% (13/30) of endo and ectoparasites, respectively, in wild boars, with the identification of eggs of Metastrongylus spp., Strongyloides ransomi, Trichuris suis, Stephanurus dentatus, and nematodes of the order Strongylida, as well as oocysts of Eimeriidae protozoa. Ectoparasite infestations were mainly caused by ixodids of the genus Amblyomma spp. and by larvae of Cochliomyia hominivorax.

Predicting Landscape Conversion Impact on Small Mammal Occurrence and the Transmission of Parasites in the Atlantic Forest

ABSTRACTAimChanges in landscape configuration significantly impact ecosystems and the services they provide, including disease regulation for both humans and wildlife. Land use conversion usually favors disturbed‐adapted species, which are often known reservoirs of zoonotic parasites, thereby potentially escalating spillover events (i.e., the transmission of parasites to new hosts, including humans). Here we aimed to investigate how alterations in landscape use and configuration influence the distribution and co‐occurrence of potential hosts of zoonotic and epizootic parasites.LocationBrazilian Atlantic Forest.Time PeriodData collection spanned from 1997 to 2019.Major taxa studied small mammals.MethodsWe integrated ecological network metrics and joint distribution models while accounting for phylogenetic relationships and functional traits to answer two main questions: (1) do small mammal species considered central hosts in the transmission of parasites exhibit a higher probability of occurrence in landscapes with reduced native vegetation areas? (2) Do small mammal hosts that share a higher number of parasites have higher co‐occurrence probabilities?ResultsOur results demonstrated that species identified as significant hosts in our centrality network analysis displayed an increased probability of occurrence in landscapes that are both more fragmented and have a higher proportion of farming areas, hence fewer native vegetation areas. Regarding the relationship between species co‐occurrence and parasite sharing, our findings indicated that most strong co‐occurrences were prevalent within groups with higher parasite fauna similarity, but not all species sharing parasites had a higher probability of co‐occurring.ConclusionsHere we highlight the effects of landscape conversion on small mammal species, including how different configurations of land use can influence both central and non‐central host occurrences. Besides, our results also indicate that parasite transmission may be overestimated when the co‐occurrence probability of potential host species is not considered. We highly recommend incorporating co‐occurrence data to estimate zoonotic risk.

Gyrodactylus serrai n. sp. (Gyrodactylidae), from the Near-Threatened Clanwilliam Sawfin, Cheilobarbus serra (Peters) (Cyprinidae, Smilogastrinae), in the Cape Fold Ecoregion, South Africa

A new species of Gyrodactylus is described from the gills of the near-threatened Clanwilliam sawfin, Cheilobarbus serra (Smiliogastrinae) collected from the Matjies River, Cape Fold Ecoregion, Western Cape Province, South Africa. Morphometry and morphology of the haptoral hard parts (hamuli, bars and marginal hooks) of Gyrodactylus serrain. sp. differ from the other known species of the genus in the smaller size of hamuli and the shape and size of marginal hooks. Furthermore, ITS rDNA for the new species is unique among available Gyrodactylus spp. data in GenBank. Based on the uncorrected p-distances, G. serrain. sp. is genetically most closely related to Gyrodactylus moroccensis Rahmouni, 2023 and Gyrodactylus pseudomoroccensis Rahmouni, 2023 from two species of Luciobarbus (Barbinae) from northern Africa, with interspecific divergence of 8.7% and 8.8%, respectively. The presence of a median ridge in the terminal part of the ventral bar membrane at G. serrain. sp. most probably represents a morphological link to the North African Gyrodactylus spp. that suggests a morphogenetic association across the African continent as a result of ancient waterways that facilitated the dispersion of cyprinids and their parasite fauna or an independent evolution event retaining similarities from a common ancestor. The description of Gyrodactylus serrain. sp. represents only the second species of Gyrodactylus described from an endemic South African cyprinid host, underscoring the need for focused research on this group of fishes to provide a sound understanding of the parasitic communities of these highly threatened and poorly studied hosts.

Metazoan parasite fauna of grey mullet (Mugilidae) from the coastal waters of Vietnam

A total of 201 fishes of the family Mugilidae caught off central Vietnam (Nha Trang Bay) were examined for parasites. Eight species of Mugilidae were identified based on cytb and 16S rRNA sequences. Protozoa were not revealed. The metazoan parasites belong to six higher taxa. Myxozoa Grassé, 1970 is represented by six genera, three of which were first found in grey mullets off Vietnam. The specimens of Monogenea Van Beneden, 1858 belong to two genera: Ligophorus Euzet et Suriano, 1977 and Metamicrocotyla Yamaguti, 1953. Twelve species of the former were recorded for the first time both in the coastal waters of Vietnam and in the East Sea. Trematoda Rudolphi, 1808 is represented by the members of the four families, of which only three species, Haplosplanchnus pachysoma (Eysenhardt, 1892), Pseudohaploporus planilizum Atopkin, Besprozvannykh, Ha, Nguyen, Nguyen & Chalenko, 2019 and Spiritestis arabii Nagaty, 1948, were identified. The latter was first recorded in the East Sea. Acanthocephala Rudolphi, 1808 specimens belong to the species Neoechinorhynchus dimorphospinus Amin & Sey, 1996. Crustacea Brünnich, 1772 are represented by five families, of which only the copepod Lernanthropsis mugilii (Shishido, 1898) and the isopod Nerocila orbignyi (Guérin, 1832) were identified. Hirudinea Savigny, 1822 were not determined to genus and species level. A total of 25 species of parasites were found in the Mugilidae fishes examined in Nha Trang Bay. In general, 96 species of parasites are currently documented in these fishes in the East Sea, 55 of which occur off Vietnam. As a result of this study, carried out off central Vietnam, 16 parasite species were recorded in grey mullet for the first time in Vietnamese coastal waters and 15 for the first time in the East Sea. Thus, extending the geographical range of the studies may result in new records of parasites in these fishes.

Study of parasitosis in laboratory mice and rats in different types of vivariums

The purpose of the research is to study the parasite fauna in laboratory rats and mice in SPF-status and open-type vivariums and to compare the infection rate depending on the maintenance type within each type of samples.Materials and methods. The studies were conducted using life-time diagnosis (flotation method and Scotch-tape test), and the material were fecal samples from laboratory rodents and litter samples. Ten percent of the vivarium population and all newly arrived mice and rats in quarantine were examined. Fifty-four individual samples from pure line mice, and 24 litter samples were examined. A total of 234 samples were collected from the laboratory rats: 93 individual samples, 55 combined samples, and 17 sawdust samples; 69 samples were examined by Scotch-tape test.Results and discussion. Twenty six percent of the laboratory SPF vivarium mice were found to have protozoa: Giardia muris (11.1%) and Trichomonas sp. (20.4%). Nematodes Aspiculuris tetraptera (51.0%) and Syphacia obvelata (20.6%), and cestode Rodentolepis nana (12.0%) were recorded in the open-type vivarium mice. The laboratory open-type vivarium rats were found to have nematodes S. muris (up to 60.9%), A. tetraptera (5.4%), Trichosomoides crassicauda (1.8%), cestode R. nana (27.3%), protozoa Eimeria sp. (7.2%) and Giardia sp. (9.0%). The compared infection of individual with combined mouse fecal samples showed statistically significant differences for all parasites in general and for individual species. Pairwise comparisons of the infection showed that the combined sample detected R. nana statistically significantly more often versus the individual sample (27.3 vs. 5.4%, P < 0.001). The comparison of the infection depending on the type of rat maintenance within each sample type did not show statistically significant differences.

First record of metazoan parasites of hybrids between the genera Colossoma and Piaractus in natural environments.

The practice of hybridization is carried out globally in fish farms. Here, we present the first record of the parasitic fauna of hybrids among genus Colossoma and Piaractus in natural environments. We identified a total of 48 hybrids, nine F1 hybrids (nuclear DNA from both species present in the cross) and 38 advanced hybrids (nuclear DNA from one species), both from crosses between Piaractus brachypomus and Piaractus mesopotamicus, and one F1 "tambacu" corresponding to cross between Colossoma macropomum and Piaractus mesopotamicus. This is the first record of Anacanthorus penilabiatus, Anacanthorus toledoensis, Mymarothecium viatorum, Mymarothecium ianwhittington, Haementeria sp., Dadaytrema oxycephala, Rondonia rondoni, and Echinorhynchus gomesi parasitizing hybrids collected in a natural environment. With this, we expand knowledge about the diversity of fish and parasites in the upper Paraná River and warn about the risk that fish escapes can cause in the basin.

Preliminary Study on Ecto and Endoparasites of the Black Rats (Rattus Rattus) in Benghazi City

Forty-five adult trapped black rats (Rattus rattus), 24 males and 21 females, were dissected and examined in this study for ecto and endoparasites. Three ectoparasites were detected, namely, the flea (Xenopsallya cheopis), mites (Ornithonyssus bacoti), and tick (Ixodes spp) with 48.9%, 13.3%, and 2.2% respectively. Meanwhile, many species of endoparasites were: Entamoeba histolytica/dispar (73.3%), Entamoeba coli (31.3%), Blastocystis hominus (8.9%), Giardia lamblia (15.6), Chilomastix sp. (4.4%), a coccidia sp. (13.3%), Hymenolips nana (2.2%), Hymenolips diminuta (44.4%), and Taenia taeniaformis (6.7%), and Moniliformis moniliformis (2.2%). Of all examined rats, 97.8 % (44/45) were found to harbor at least one parasite species with no significant differences between body weight, body length, and gender of the host with the prevalence of parasite species. Multiple infections occurred at six species per rat with different combinations of parasite infections. These results are the first records of the parasitic fauna of R. rattus in the Benghazi area.

Comparative Study of Community Analysis of Plant Parasitic and Free-living Nemic Fauna around Root Zones of Mango (Mangifera indica) Plant in Hapur Region

Nematodes are tiny rounded body, unsegmented worms. They occupy any niche of the environment, like soil, freshwater, and terrestrial (free-living and parasitic). They constitute a large group of all metazoans in the world: Plant-parasitic and free-living nematodes are well-recognized factors in soil productivity. Phytonematodes feed upon the cell sap of plants with the help of stylet. It causes many abnormalities in plants like gall formation on roots, stunting growth, wilting of plants, and serious damage to crop yield. In the present study, soil samples were collected from (0-30 cm) vertical depth and (30-60 cm) horizontal depth from around the root of the mango plant in the Hapur region from July to November. Nematodes samples were extracted by decanting and sieving Techniques (Cobb1918) were applied. Under the microscope examination nematodes were identified as free-living with minimum percentages of 14.2% and8.88% at both vertical and horizontal depth while plant parasitic nematodes were recorded as a higher percentage(53.90% vertical depth)and(64.91% horizontal depth) away from the host plant. This was variation in communities of plant nematodes at both depths due to seasonal changes, various other edaphic factors such as PH, temperature, moisture emergence of secondary rootlets, and availability on set of monsoon season and unavailability of various food resources.

Diversity and ecological relationships of Cestoda and Monogenoidea parasites of freshwater stingrays (Myliobatiformes, Potamotrygonidae), in the upper Paraná River, Brazil

The Neotropical freshwater stingrays of Potamotrygon genus present a unique and complex natural history and biogeographical pattern that can be traced to a marine origin and the colonization of the continental environment during the Miocene. During the evolution of potamotrygonids, several species of the parasitic fauna coevolved and co-opted concomitantly to their hosts during the colonization of the new environments. One striking example can be observed during the colonization of the upper Paraná River region. However, few studies explored the ecological and taxonomic aspects of potamotrygonid parasites. In this work, we investigate aspects of the ecology and taxonomy of the species of Monogenea and Cestoda that are parasites the species of freshwater stingrays of the genus Potamotrygon in the upper Paraná River. Our results indicate that at least six species of parasites are present in potamotrygonids in the region. Two of the observed parasites are putative new species and three of the parasitic species were identified for the first time in the region, hence expanding their geographic distributions. We quantified ecological aspects at different levels of communities for the collected parasite species. We compared the diversity in different locations and hosts and performed an exploratory analysis to investigate the differences in parasite abundance. Additionally, an identification key for the Monogenea and Cestoda species of the sampled region is provided.

On the fauna of parasites of the gastrointestinal tract of small ruminants in the mountainous zone of Armenia

The aim of the research is to study the parasitic invasion of small ruminants in the mountainous zone of Armenia during summer and autumn, in this case to determine the invasiveness of parasites of the digestive tract of sheep.The material was feces collected from sheep on pastures in the coastal zone of the Getik River during 2022. The work was carried out at the Scientific Centre of Zoology and Hydroecology, National Academy of Sciences, Republic of Armenia. The material researched also included mollusks and oribatid mites – intermediate hosts of biohelminths.As a result of the study of parasitic invasion of small ruminants in the mountain zone of Armenia, the taxonomic composition of parasites was determined. Helminths found in sheep belong to the classes Trematoda, Nematoda, and Cestoda, protozoa – to the class Protozoa.In the autumn season, representatives of seven genera of parasites of the gastrointestinal tract were found – Moniezia, Dicrocoelium, Fasciola, Nematodirus, Strongylus, Trichuris, Eimeria, while in the summer season, only representatives of five genera were found – Moniezia, Dicrocoelium, Nematodirus, Strongylus, Eimeria.As a result of these studies, it can be concluded that natural and climatic factors of the environment have a significant impact on the structure of the helminth complex of sheep in the mountain region of Armenia.All parasites found can have a detrimental effect on the sheep's body. However, the severity of the invasion in the samples taken is not at the level that could lead to serious diseases in sheep. This suggests that the treatment methods used on farms are at a fairly high level.

Biogeography of larval trematodes in the freshwater snail, Semisulcospira libertina: a comparison of the morphological and molecular approaches

While biogeographic patterns of free-living organisms are well documented, the biogeography of parasitic fauna remains largely unclear. Due to morphological similarities, parasites are often difficult to identify without the aid of molecular genetics, further complicating the interpretation of their biogeographic patterns. We investigated trematode parasites infecting the East Asian freshwater snail Semisulcospira libertina to understand their biogeography and to evaluate how molecular approaches influence the interpretation of biogeographic patterns of the trematode fauna. We identified 46 genetically delimited species from 19 morphologically distinguishable trematodes infecting S. libertina and found that their species richness was negatively correlated to latitude. We also found that potential definitive host (fishes) richness and host body size were positively correlated with trematode species richness, suggesting that host attributes are essential factors shaping the biogeographic pattern in trematodes. These trends were observed irrespective of species identification methods, demonstrating that classical morphological identification can also effectively identify the latitudinal gradient pattern in trematodes. We further detected the distance decay of similarity in trematode communities, although this trend was only detectable in the biogeographic dataset based on molecular identification. Our study showed that morphological identification sufficiently reflects the latitudinal richness gradient while molecular identification is essential to estimate accurate local species richness and increase the resolution of the large-scale pattern of population similarities in the trematode communities.

Temporal change in the parasite community of an invasive fish Trachelyopterus galeatus (Siluriformes: Auchenipteridae) in a neotropical floodplain.

The construction of dams and hydroelectric plants affects biodiversity in aquatic environments and can facilitate the invasion of species. Few studies assess the long-term response of parasite fauna under these events. The aim of this study was to investigate possible changes in the endoparasite composition of the invasive catfish Trachelyopterus galeatus (Linnaeus, 1766) in the floodplain of the upper Paraná River over a 27-year study period. A total of 79 fish were collected in period 1 (1993) and 31 in period 2 (2019/2020) at the same sampling points, and the endoparasites were located in the gastrointestinal system using a stereomicroscope. It was found that the development of the fish and the composition of their endoparasitic fauna changed over time. In the second period, the fish presented smaller values for mass (g) and standard length (cm) when compared to period 1. It was found that three species of endoparasites were found per period, but although the richness was the same, the composition differed, and only one digenean (Microrchis oligovitellum Lunaschi, 1987 (Trematoda: Paramphistomidae)) was shared. The Porto Primavera Dam was built upstream of the site between the sampling periods (1999) and caused a number of environmental changes, possibly being the main factor responsible for changes in components of the parasite community. Anthropic modification to an environment can cause loss of diversity and loss of ecological interactions. Through our results, we emphasize the importance of including parasite fauna in studies that assess environmental impacts.

First report of the presence of Pseudoterranova sp. in the body cavity of salmon (Salmo salar) from the Baltic Sea

Abstract Despite salmon (Salmo salar L.) being an important fish in the Baltic Sea ecosystem and its fisheries, knowledge about the parasite fauna of this top predator is scarce. The Anisakidae nematodes (Anisakis spp., Pseudoterranova spp., Contracaecum sp.) found in Baltic Sea fish species are zoonotic parasites that are hazardous to human health. Due to the marked increase in the numbers of grey seal (Halichoerus grypus), the definitive host of Contracaecum sp. and Pseudoterranova spp., increased dispersion of these parasites has been observed in recent years. The aim of our study was to investigate salmon caught in Polish marine waters for the presence of Anisakidae nematodes. Parasitological inspection of the body cavities of 89 individual salmon was conducted in 2012 and revealed the presence of a Pseudoterranova sp. L3 larva. The presence of the parasite is reported here for the first time in the muscle tissue of salmon from the Baltic Sea. The presence of Anisakidae nematodes in commercially important fish species may have implications for human health since these parasites pose a risk of anisakidosis.

Testing Mini-FLOTAC for the Monitorization of Gastrointestinal Parasitic Infections in Birds Kept at Four Iberian Zoological Institutions

Birds kept in zoological institutions are highly exposed to gastrointestinal (GI) parasitism caused by coccidia and nematodes. The current research aimed to characterize the avian GI parasitic fauna in several zoological collections in Portugal and Spain. During the full year of 2022, a total of 120 fecal samples were collected from four zoological institutions: Lisbon Zoo, Olivais Pedagogical Farm, and Avian Biodiversity Center (Lisbon, Portugal), and Avifauna park (Lugo, Spain). Analysis was conducted in domestic bird species (autochthonous and exotic poultry breeds), and 18 different exotic bird species like Galliformes (peacock, pheasant), Anseriformes (duck), Psittaciformes (parrot, macaw, cockatiel, parakeet, cockatoo), Coraciiformes (motmot), Charadriiformes (avocet), Strigiformes (owl), Phoenicopteriformes (flamingo), Struthioniformes (ostrich), Rheiformes (rhea), and Casuariiformes (emu, cassowary). Feces were processed using Mini-FLOTAC (MF), to identify parasitic forms and quantify their shedding (oocysts or eggs per gram of feces). Moreover, 15 fecal samples from pheasants were also processed using the McMaster method (McM), to compare the parasite shedding and frequencies between techniques. MF implementation allowed identification of coccidia infections in all bird collections. Also, peacocks of the Lisbon Zoo tested positive for Trichostrongylus tenuis and Strongyloides pavonis, and the exotic birds from Avifauna park were also positive for several nematode species, with Ascaridia sp., Capillaria sp., Strongyloides sp., and Syngamus trachea eggs being detected in pheasants’ feces. Moreover, the analysis of pheasants’ feces with MF detected prevalences of 33% for coccidia oocysts, and 47% for Capillaria sp. and Ascaridia sp. eggs, while McM detected prevalences of 13%, 27%, and 40% for the respective parasite taxa, with no differences being observed between methods (p = 0.39, p = 0.45, and p = 0.50, respectively). This research provided more scientific support regarding the importance of using Mini-FLOTAC in routine parasitological diagnosis in birds kept at zoological institutions.

Echinococcus multilocularis and Other Intestinal Parasites of the Red Fox (Vulpes vulpes) from the Pomerania Region, Northern Poland.

The aim of the study was to determine the species composition of the intestinal parasite fauna of foxes from the Pomerania region, with a particular emphasis on helminth species considered dangerous to humans, and to determine their prevalence and intensity of infection. In total, 165 digestive systems from foxes inhabiting the Pomeranian region were examined. The prevalence of intestinal parasites among the studied foxes was 61.8%. Our findings confirm that foxes in Pomerania carry various parasites, some of which pose a direct threat to human health. As such, constant monitoring of their infestation is essential. Particular attention should be paid to parasite species with potential for transmission to humans, such as Echinococcus multilocularis, Alaria alata and Toxocara canis, whose respective prevalence was found to be 10.9%, 17.6% and 28.5%.

Polyparasitic associations in deer from the Republic of Moldova

The analysis of parasitic fauna in deer from the natural reservations of the Republic of Moldova revealed a high level of parasite infestation, in which associations of two or more parasite species predominate. Out of total number of 14 parasite species identified in cervids, only three species (Eimeria austriaca, E. ponderosa, E. capreoli) are characteristic for them, while the other 11 parasite species identified (D. lanceolatum, F. hepatica, P. cervi, S. papillosus, C. punctata, O. ostertagi, T. vitulorum, T. axei, M. benedeni, E. asymmetrica, E. bovis) are common not only to cervids but also to the domesticated ruminants. The level of parasitic infestation of deer from the Natural Reservation „Plaiul Fagului” is characterized by the mixture of parasitic forms, with 36,1% higher incidence in noble deer, 30,3% higher in the sika deer and 13,0% higher in roe deer compared to those from the Natural Reservation „Codrii”, due to the specific biotope and the complementary foraging of the deer in difficult seasonal periods.

Specifics of <i>Anisakis simplex</i> larvae infection in the Pacific herring <i>Clupea pallasii</i> Valenciennes, 1847 from Lake Tunaicha

The purpose of the research is to analyze specifics of Anisakis simplex larvae infection in the body cavity of the lake Pacific herring in Lake Tunaicha (from materials of 1980 to 1995).Materials and methods. Conventional parasitological methods were used for collecting the material. The dissection recorded the number of nematodes in the fish. Parasitological studies of the herring from Lake Tunaicha (southern Sakhalin) were conducted from 1980 to 1995. A total of 4,438 fish caught in the Krasnoarmeyskaya channel and Lake Tunaicha were examined.Results and discussion. The parasite fauna in the herring from Lake Tunaicha included six parasite species of which two nematode species (Anisakis simplex l., Hystorethylacium aduncum l.), one acanthocephala species (Corynosoma strumosum juv.), one trematode species (Brachyphalus crenatus) and two parasitic copepod species (Ergasilus wilsoni and E. hypomesi). Among all the above species, A. simplex larvae were of greatest interest for study. The helminth is a typical species of the Pacific herring and poses a threat to human and animal health. The results of the studies found no difference in the infection of herring females or males in Lake Tunaicha. A change in the infection rate was demonstrated in the herring by age and linear dimensions depending on the fish life cycle (spawning and wintering migration periods). The first cases were recorded for herrings infected with Anisakis sp. larvae sized from 14 cm.

Two proteocephalid cestodes in the fish Malapterurus electricus and Heterobranchus bidorsalis from Lake Nasser, Egypt: a morphological, molecular, and histopathological study

Despite the importance of the electric catfish (Malapterurus electricus) and the African giant catfish (Heterobranchus bidorsalis) in the foodweb of Lake Nasser, Egypt, little is known about their diseases and parasitic fauna. This work describes, for the first time, cestodiasis in M. electricus and H. bidorsalis. Corallobothrium solidum and Proteocephalus sp. were identified morphologically and molecularly from M. electricus and H. bidorsalis, respectively. Using PCR, sequencing, and phylogenetic analysis, the two cestodes shared rRNA gene sequence similarities yet were unique and the two new sequences for the proteocephalid genera were submitted to the GenBank database. The prevalence of infection was 75% and 40% for the two fish species, respectively. Infections significantly increased in the summer and spring and were higher in female fish than in male fish. The intestine was the preferred site of the two adult cestodes. However, in the case of C. solidum some larval cestodes were found outside the intestine in between the skin and abdominal musculature, attached to the mesentery, and within intestinal tunica muscularis. Desquamation of the intestinal epithelium and inflammation at the site of infection in addition to congestion of the intestinal wall of the tapeworm infected fish were evident, indicating that C. solidum and Proteocephalus sp. impacted the infected fish. The larval stages of C. solidum attempted to penetrate the intestine and sometimes they were encircled within fibrous layers infiltrated with inflammatory cells. The infected fish’s musculature was free of cestode infections. Preventive measures should be implemented to prevent the spread of infections.

Study of Parasitary Fauna in Tilapia of Fish Cultures in the Distrito Federal

Objective: This article discusses the parasitic fauna found in tilapia, the most produced in the DF, collected in fish farms and presents an analysis of water quality, a relative condition factor and the influence of seasonality on the average abundance of parasites. Methodology: For each acquisition campaign, ten fish were collected from each visited fish farm, totaling 180 sampled fish. The fish were collected by fishing nets with mesh 14 and transported in thermal boxes, with each specimen properly packed in a plastic bag, to ensure protection during transport to the Aquaculture Laboratory of the University of Brasília (AcquaUnB). Results and Conclusion: In the two acquisition campaigns, parasitism by Trichodina sp., Monogenoids, Ichthyophthirius multifiliis and Apiosoma sp. Infestations by Trichodina sp. presented higher prevalence and average intensity than other parasites in general, followed by infections by Monogenoides, Ichthyophthirius multifiliis and Apiosoma sp, respectively. The average abundance of Trichodina sp., monogenenoids, Ichthyophthirius multifiliis and Apiosoma sp. showed a positive correlation with temperature and the concentration of ammonium and phosphate in fish farm water. On the other hand, the average abundance of parasites showed a negative correlation with the levels of dissolved oxygen and nitrate concentration. The ectoparasites found do not directly affect human health. There was a significant difference between the average abundance of parasites found in fish collected in the months of February and August, so that the highest parasitic rates were observed in February, when there is greater rainfall in the Federal District and when the values of water parameters were findings. less suitable.

Svalbard rock ptarmigan: a first glimpse into parasite infections

Natural ecosystems are under stress due to climate change and impacts are especially prominent at high latitudes. Manifestations of these changes include northward shifts in the distribution of birds, phenological mismatches, improved survival of parasites in the environment and the arrival of new parasite vectors and intermediate hosts. We collected baseline data on parasite infections in the Svalbard rock ptarmigan (Lagopus muta hyperborea), which is endemic to two High Arctic archipelagos, by sampling 10 birds caught in September–October 2015 in Van Mijenfjorden, Spitsbergen. Five species were found, three endo- and two ectoparasites. The endoparasites included a nematode, Heterakis sp. (prevalence 10%), and two species of Eimeria, all with direct life cycles. The Eimeria species are provisionally called Eimeria sp. A and sp. B (prevalence 50% and 20%; mean intensity 1560 and 1850 oocysts per g faeces, respectively). Both show morphological similarities with known rock ptarmigan eimeriids, but further taxonomic research is needed to describe their phylogenetic relationships. The two ectoparasites, the ischnoceran chewing lice Goniodes lagopi and Lagopoecus affinis, both showed 90% prevalence and a mean intensity of 18.3 and 5.6, respectively. The eimeriids are host specific, and the chewing lice are common parasites of closely related grouse species. On the basis of our knowledge of rock ptarmigan parasites, Heterakis sp. is considered a generalist parasite. The parasite fauna of the Svalbard rock ptarmigan is impoverished compared with conspecific populations in other Arctic locations, such as Iceland and Greenland.