Parasitological and molecular survey of scattered parasitism by trichomonads in some avian species in Iran.

Outbreaks of avian trichomonosis are being reported worldwide; meanwhile, the genetic and virulence variations are under investigation. In this study, the occurrence and genetic variability of oral or faecal trichomonads among various avian species were investigated. Samples obtained from either the oropharyngeal cavity, crop/oesophagus, droppings/cloaca, or conjunctival swabs of avian species were inspected for flagellates. Phylogenetic analysis of partial ITS1-5.8s rRNA-ITS2 sequences from selected samples was performed to investigate the genetic diversity of the isolates. Investigation of 737 birds revealed an infection rate of 15.7% in the upper gastrointestinal tract, 7.3% in the faecal samples, and 0.7% involvement of the conjunctiva. Phylogenetic analysis of partial ITS1-5.8s rRNA-ITS2 sequences from selected samples, identified genotypes A and B of Trichomonas gallinae and genogroups A-C and E of Tetratrichomonas gallinarum. A novel ITS genotype of intestinal trichomonads was also detected in hooded crow (Corvus cornix) and common mynah (Acridotheres tristis). In the present study, in addition to Columbiformes and Falconiformes, trichomonads were detected in Passeriformes and Galliformes with the involvement of organs other than the gastrointestinal tract. Genotype A T. gallinae was detected in domestic pigeons (Columba livia domestica), a laughing dove (Spilopelia senegalensis), a common kestrel (Falco tinnunculus), a budgerigar (Melopsittacus undulates), and a canary (Serinus canaria). Distinct genotype B was detected in a common mynah and a budgerigar. Genogroups A-C of T. gallinarum were also demonstrated in Galliformes and Anseriformes. Furthermore, two novel trichomonad ITS genotypes were detected in hooded crows and a common mynah warranting detailed multi-locus molecular analysis.RESEARCH HIGHLIGHTSITS diversity of trichomonads was shown in various avian species.Diversity of the parasites' target organ and clinical manifestations was demonstrated.Two novel ITS genotype trichomonads from common mynah and hooded crow were identified.

Helminthes in the Small Intestine of the Common Eider (Somateria mollissima) from the Eastern Murman: Impact on the Host Digestive Activity and Physiological State.

In this ecological and physiological study of the common eider (Somateria mollissima) nesting on the coast of Eastern Murman, the species composition of the bird helminth fauna, as well as the infection quantitative parameters, were determined. The common eider small intestine proved to be infected with trematodes of the genus Microphallus; three species of cestodes, namely, Lateriporus teres (Cestoda: Dilepididae), Fimbriarioides intermedia (Cestoda: Hymenolepididae), and Microsomacanthus diorchis (Cestoda: Hymenolepididae); and one species of acanthocephalan, Polymorphus phippsi (Palaeacanthocephala: Polymorphidae). At the sites of F. intermedia and M. diorchis locations within the intestine, the protease activity was reduced while in the foci infected with acanthocephalan P. phippsi, it was, on the contrary, increased. Glycosidase activity in the intestinal mucosa was reduced as compared to the control in birds infected by the cestodes M. diorchis. Hematological indices of the infected individuals were higher than the control parameters.

The endogenous development and pathogenicity of Eimeria anseris (Kotlan, 1932) in domestic goslings.

Twenty-one, 25-day-old, artificially reared, coccidia-free goslings (Anser cygnoides var. domestica) were inoculated orally with 0.5 × 104, 1 × 104, or 100 × 104 sporulated oocysts of Eimeria anseris and sacrificed at intervals from 24 to 216 h post-inoculation (HPI). Nine uninfected goslings served as negative controls. Parts of the visceral organs from goslings, including the intestines, kidneys, and liver, were fixed, sectioned, and observed microscopically. The results revealed that two generations of meronts occurred in the life cycle of E. anseris. The first generation of meronts developed at 24-96 HPI and the second generation at 90-128 HPI. Each meront contained 4-10 merozoites. Development of gamonts began at 128 HPI and mature oocysts appeared at 168 HPI. Developmental stages presented mainly in the epithelial cells of crypts and lamina propria in the posterior parts of the jejunum and ileum. Parasites localized mostly in the cytoplasm and occasionally in the nuclei of host cells. Histological lesions were pronounced in the jejunum and ileum. Desquamation and necrosis of the epithelium of intestine and crypts, infiltration of inflammatory cells, and hemorrhage and mucosal edema were associated with aggregates of endogenous stages. The infected goslings mainly showed severe diarrhea, depression, anorexia, and emaciation, suggesting that E. anseris is highly pathogenic in goslings.

Spatiotemporal distributions of intestinal helminths in female lesser scaup Aythya affinis during spring migration from the upper Midwest, USA.

We examined the associations between intestinal helminth infracommunity structure and infection parameters and the age, size, and year and region of collection of 130 female lesser scaup (Aythya affinis) during their 2014-2015 spring migrations through the upper Midwest, USA. We identified a total of 647,174 individual helminths from 40 taxa, including 20 trematodes, 14 cestodes, 4 nematodes and 2 acanthocephalans parasitizing lesser scaup within the study area. Lesser scaup were each infected with 2-23 helminth taxa. One digenean, Plenosoma minimum, is reported for the first time in lesser scaup and in the Midwest. Mean trematode abundance and total helminth abundance was significantly less in 2015 than 2014, and we suspect that colder weather late in 2015 impacted the intermediate host fauna and caused the observed differences. Brillouin's species diversity of helminths was greatest in the northernmost region of the study area, which coincides with the range of a non-indigenous snail that indirectly causes annual mortality events of lesser scaup. While host age and size were not determined to be influential factors of helminth infracommunity structure, non-parametric ordination and permutational analysis of co-variance revealed that year and region of collection explained differences in helminth infracommunities. Our results suggest that spatiotemporal variations play an important role in the structure of intestinal helminth infracommunities found in migrating lesser scaup hosts, and may therefore impact host ability to build endogenous reserves at certain stopover locations in the Midwest.

Nematodes in the mallard (Anas platyrhynchos Linnaeus, 1758) and the common goldeneye (Bucephala clangula Linnaeus, 1758) (Anatidae) from Northern Europe.

There are first data on nematodes of Anas platyrhynchos Linnaeus, 1758 (mallard) and Bucephala clangula Linnaeus, 1758 (common goldeneye) from Northern Europe (Ladoga Lake region). The ducks were found to be infected with nine nematode species. A. platyrhynchos hosted eight nematode species and B. clangula was host to four nematode species. All species except Capillaria anatis were found in the region for the first time. Nematodes Amidostomum acutum, Streptocara crassicauda, and Tetrameres fissispina parasitized on both hosts and were the most abundant. The biggest number of parasites revealed was biohelminths with a direct life cycle.

Description of Diorchis thracica n. sp. (Cestoda, Hymenolepididae) from the ruddy shelduck Tadorna ferruginea (Pallas) (Anseriformes, Anatidae) in Bulgaria.

Diorchis thracica n. sp. (Cestoda, Cyclophyllidea, Hymenolepididae) is described from the ruddy shelduck Tadorna ferruginea (Pallas) (Aves, Anseriformes, Anatidae), collected in the vicinities of Radnevo, Stara Zagora Region, Bulgaria. The new species is differentiated from other members of Diorchis Clerc, 1903 by possessing rostellar hooks with length of 36 µm, a thick-walled cirrus-sac with strong longitudinal muscular fibres in its middle part and a copulatory vagina with two sphincters. Main morphological criteria for distinguishing species of the genus Diorchis are discussed.

AVIAN HAEMOSPORIDIANS IN GREATER SCAUP (AYTHYA MARILA) AND LESSER SCAUP (AYTHYA AFFINIS) FROM WISCONSIN.

Avian haemosporidians are a diverse group of protozoan parasites that infect a wide range of host species. Waterfowl are an ecologically and economically important group of hosts that have been underrepresented in studies of haemosporidians. Diving ducks have unique life history traits, and morphological, behavioral, and dietary differences separate them from more common dabbling ducks. Greater scaup (Aythya marila) and lesser scaup (Aythya affinis) are closely related diving ducks with declining population trends in North America. To better understand the diversity of haemosporidians within diving ducks and factors related to host infections in scaup, we surveyed 82 hunter-donated waterfowl from 8 species of divers, sea ducks, and dabblers from Green Bay, Wisconsin from 2019 to 2021. We used molecular detection methods and phylogenetic and statistical analyses to describe the diversity, host associations, and prevalence of haemosporidians. We detected 14 unique genetic lineages of haemosporidians, including 4 novel lineages. We identified at least 1 lineage of haemosporidian in each of the 8 host species of divers, sea ducks, and dabblers examined. Lesser scaup had more diverse haemosporidian communities than did greater scaup, but lineages showed no clustering among these hosts when incorporated in phylogenetic analyses with lineages from other Nearctic waterfowl. Female lesser scaup had the highest infection prevalence, but there was no effect of host age or year of sampling. Our findings underscore the importance of species and sex differences that could lead to a higher risk of infections. Our results also fill an important geographical sampling gap for haemosporidians along a key migratory route. Increased monitoring of haemosporidians in waterfowl could contribute to insights into parasite evolution and ecology and the conservation and management of host populations.

Digenean communities in the tufted duck [Aythya fuligula (L., 1758)] and greater scaup [A. marila (L., 1761)] wintering in the north-west of Poland.

A total of 124 specimens of the tufted duck, Aythya fuligula, and 63 greater scaup, A. marila, were examined for digenean parasites. Both duck species, which overwinter in a coastal lake connected with the southern Baltic (north-west Poland) were found to support Amblosoma exile, Cyathocotyle prussica, Paracoenogonimus ovatus, Australapatemon minor, Cotylurus cornutus, Echinoparyphium recurvatum, Echinostoma revolutum and Notocotylus attenuatus. In addition, the tufted duck hosted Hypoderaeum conoideum, Bilharziella polonica, Neoeucotyle zakharovi, Renicola mediovitellata, Psilochasmus oxyurus, Psilostomum brevicolle and Cryptocotyle concava; Echinostoma nordiana occurred in the greater scaup only. The two duck species differed significantly in the intensity and abundance of their digenean infection. Aythya marila harboured higher intensity levels and a wider assemblage of digeneans than A. fuligula, and this was likely to be due to differences in the pre-wintering exposure of the duck species to infective stages of these freshwater digeneans. Digenean communities in both duck species, strongly dominated by E. recurvatum, were relatively similar in their structure. No significant sex-dependent differences in digenean infections were revealed, except for the infection with N. attenuatus in A. fuligula. Similarly, there were no significant age-dependent differences (adult versus immature birds) in digenean infections, except for that with N. attenuatus in A. fuligula. The structural similarity between digenean communities in the two duck species is most likely an effect of overlapping diets based on freshwater molluscs, components of the digenean transmission pathway to definitive hosts.

Description of Sarcocystis anasi sp. nov. and Sarcocystis albifronsi sp. nov. in birds of the order Anseriformes.

On the basis of the already published morphological, 18S rDNA, 28S rDNA data (Kutkiene et al., Parasitol Res 99:562-565, 2006; Parasitol Res 102:691-696, 2008; Parasitol Res 104:329-336, 2009), and ITS-1 region investigation results of sarcocysts presented in this paper, Sarcocystis albifronsi sp. nov. from the white-fronted goose (Anser albifrons) and Sarcocystis anasi sp. nov. from the mallard duck (Anas platyrhynchos) are described.

Influence of petroleum hydrocarbons on the endoparasitic helminths of the common eider, Somateria mollissima, from Newfoundland.

A comparison of commonly occurring metazoan parasites in the digestive tract was made between common eiders, Somateria mollissima, that were contaminated with oil and reference birds confiscated from illegal hunting. There was a greater number of commonly occurring parasites and their abundance in reference than in oiled eiders. Except for an acanthocephalan, Polymorphus botulus, which was embedded in the wall of the intestinal tract, most of the other taxa of parasites, including trematodes, cestodes and nematodes, were probably voided from the birds following ingestion of oil. Reference eiders harboured fewer species and a substantially lower mean abundance of parasites than those studied in Newfoundland and Labrador more than four decades ago; this may be a signal of a changing prey base or an increase in prey availability as winter ice cover continues to decline.

Relationships between dietary carotenoids, body tissue carotenoids, parasite burden, and health state in wild mallard (Anas platyrhynchos) ducklings.

While rodents and other mammals have traditionally served as models for studying carotenoid physiology, many wild animals from a variety of other taxa utilize carotenoids for self-maintenance and reproduction and accumulate far greater concentrations than those found in mammals. Though we have basic understandings of the control and value of carotenoids in some wild animal systems, many gaps remain. For example, parasites and pathogens impose severe survival constraints on free-ranging organisms, but little is known of how carotenoids work in concert with the immune system to combat natural infectious challenges. Furthermore, due to the high mortality rate from which many young animals suffer, health and carotenoid status during the early stages of development may be critical to survival. The relative importance of dietary versus physiological mechanisms for carotenoid uptake has also been understudied in the wild. To begin to shed light on these issues, we studied relationships between dietary and tissue carotenoids, hematological immune parameters, and endoparasitism of wild mallard (Anas platyrhynchos) ducklings at a variety of ages. Lutein, zeaxanthin, ß-cryptoxanthin, ß-carotene, and canthaxanthin were the most common carotenoids in liver, plasma, and gut contents. We found that, early in development (when food intake is limited), carotenoids were comparatively concentrated in internal tissue (e.g., liver), presumably a carry-over from maternal contributions in yolk, but as ducklings approached independence (and increasingly fed on their own) concentrations were greatest in gut contents. Canthaxanthin concentrations were lower in the plasma and liver of older individuals compared to younger ducklings, even though gut canthaxanthin concentration did not change with age. Additionally, ß-carotene was nearly absent from circulation, despite moderate levels within the gut, suggesting a high rate of conversion to retinol. Using principal components analysis, we revealed a correlation between an increased ability to assimilate dietary carotenoids and lower levels of chronic stress (as assessed by lower heterophil-to-lymphocyte ratios) and a correlation between a reduced carotenoid status and increased investment in the immune system (as assessed by higher total leukocyte count). We also found that individuals without parasites had an overall reduced carotenoid status. Thus, we demonstrate age-specific differences in carotenoid allocation in growing animals from a precocial bird species and provide correlational evidence that parasitism and health in wild animals are related to carotenoid status and assimilation ability.

Final hosts and variability of Trichobilharzia regenti under natural conditions.

In Europe, despite of intensive work on avian schistosomes in the past, only one representative of nasal schistosomes has been detected so far, Trichobilharzia regenti, a species that remained undescribed to the scientific community until 1998. Since then, however, T. regenti has gained a considerable attention, not only due to the induction of serious lesions concomitant with the migration of the schistosomulae through the central nervous system of their natural hosts (birds) but also due to their implication in cercarial dermatitis and their neurotrophic behaviour in mammals (mice, experimental) where the parasite migrate to the CNS. From 2001 to 2010, by a parasitic control of various potential final hosts (aquatic birds) living in natural condition in France and in Iceland, we detected T. regenti in six species: Anas platyrhynchos, Cygnus olor, Aythya fuligula, Aythya ferina, Mergus merganser and Anser anser. Although morphological features, mainly of eggs, showed some variations with the original description of the parasite, molecular analysis confirmed their membership to the T. regenti species. Nevertheless, specific molecular and morphological variations were especially observed for nasal parasite isolated from Anas clypeata. For this species, we discuss the possibility for this nasal schistosome to belong to a nasal Trichobilharzia species already described in Africa or even an undescribed nasal species.

The mallard duck (Anas platyrhynchos) as intermediate host for Sarcocystis wobeseri sp. nov. from the barnacle goose (Branta leucopsis).

Morphometric and DNA investigation results of Sarcocystis wobeseri sp. nov. from the barnacle goose (Branta leucopsis) and Sarcocystis sp. (cyst type IV) from the mallard duck (Anas platyrhynchos) are presented. No significant morphometric differences between the investigated Sarcocystis species were found. ITS-1, 18S rRNA, and 28S rRNA gene sequences of these species showed 100% identity. The conclusion is drawn that it is one and the same Sarcocystis species in different intermediate hosts.

[First record of species Dicranotaenia synsacculata Macko, 1988 (Cestoda, Hymenolepididae) of the goldeneye Bucephala clangula (Linneus, 1758) in Poland]. / Dicranotaenia synsacculata Macko, 1988 (Cestoda, Hymenolepididae)--tasiemiec gagola Bucephala clangula (Linneus, 1758) notowany po raz pierwszy w Polsce.

During parasitological studies of 32 specimens of the goldeneye Bucephala clangula L., twenty seven cestode specimens were found. Four of them, isolated from the jejunum of two young female hosts, were determinated as Dicranotaenia synsacculata Macko, 1988. We based on the shape of cirrus fused with sacculus accessorius internus, shape and size of scolex and other organs. This is the first record of this species in Poland.

First detection of Enterocytozoon bieneusi in whooper swans (Cygnus cygnus) in China.

BACKGROUND: Enterocytozoon bieneusi is a parasite that infects humans and a wide range of other animals. The large migratory waterfowl, the whooper swan (Cygnus cygnus), travels through many cities during its migration and can spread parasites. Despite receiving increasing attention worldwide, there have been no reports of E. bieneusi infection occurring in C. cygnus. Therefore, this study aims to assess the prevalence and genetic characteristics of E. bieneusi in C. cygnus in Sanmenxia, China. METHODS: Altogether, 467 fresh fecal samples were collected in the Swan Wetland Park in Sanmenxia, China. Genomic DNA was extracted from fresh fecal samples (n = 467) and E. bieneusi was identified by nested PCR amplification of the internal transcribed spacer (ITS) region. ITS-positive sequences were aligned and phylogenetically analyzed to determine the genotypes of E. bieneusi. RESULTS: The overall prevalence of E. bieneusi in C. cygnus was 7.49% (35/467). Sequencing of the 35 positive samples revealed eight known genotypes (EbpA, EbpC, Henan-III, Henan-IV, BEB6, CD9, Peru6 and PtEb IX) and three novel genotypes (CSW1, CSW2 and CSW3). The phylogenetic tree constructed from the ITS sequences showed that seven genotypes (Peru6, EbpA, EbpC, Henan-III, CSW3, Henan-IV and CSW1) clustered within the zoonotic Group 1 while the remaining novel genotype CSW2 clustered within Group 5. CONCLUSIONS: To our knowledge, this is the first report of E. bieneusi in C. cygnus. Of public health significance, our results suggest that migratory C. cygnus might play an important role in the water-borne transmission of E. bieneusi. Effective strategies will be necessary to control E. bieneusi infection in C. cygnus, other animals and humans.

Relatedness and spatial proximity as determinants of host-parasite interactions in the brood parasitic Barrow's goldeneye (Bucephala islandica).

Recent studies, which have found evidence for kin-biased egg donation, have sparked interest in re-assessing the parasitic nature of conspecific brood parasitism (CBP). Since host-parasite kinship is essential for mutual benefits to arise from CBP, we explored the role of relatedness in determining the behaviour of conspecific nest parasites and their hosts in nesting female Barrow's goldeneyes (Bucephala islandica), a duck in which CBP is common. The results revealed that the amount of parasitism increased with host-parasite relatedness, the effect of which was independent of geographical proximity of host and parasite nests. Proximity per se was also positively associated with the amount of parasitism. Furthermore, while hosts appeared to reduce their clutch size as a response to the presence of parasitic eggs, the magnitude of host clutch reduction also tended to increase with increasing relatedness to the parasite. Hence, our results indicate that both relatedness and spatial proximity are important determinants of CBP, and that host clutch reduction may be an adaptation to nest parasitism, modulated by host-parasite relatedness. Taken together, the results provide a demonstration that relatedness influences host and parasite behaviour in Barrow's goldeneyes, resulting in kin-biased egg donation.

Heartworm in a mute swan (Cygnus olor).

A severely emaciated female adult mute swan (Cygnus olor) was euthanized after a period of intensive supportive care in a wild bird rehabilitation centre. Necropsy revealed severe myocardial haemorrhages in the right ventricular free wall associated with the presence of adult heartworm (Sarconema eurycerca). On histological examination, multifocal randomly scattered blood-filled cavities without endothelial or epithelial lining (migration tracts) and surrounded by necrotic debris mixed with fibrinoid deposits and a mixed inflammatory infiltrate were seen, as well as mild multifocal degeneration and necrosis of adjacent myocardial fibres. In some of the lesions, cut sections of adult female filarial nematodes revealed numerous microfilariae in their uteri. This report is the first published case of Sarconema eurycerca in a mute swan in The Netherlands.

[Description of the maritae and determination of the species status of Microphallus pseudopygmaeus sp. nov. (Trematoda: Microphallidae)].

Microphallus pseudopygmaeus belongs to the "pygmaeus" microphallids, a group of closely related species with homotypic two-host life cycle. This cycle involves one intermediate host (littoral or sublittoral gastropods, mostly of the genus Littorina), and bird-invading metacercariae develop within daughter sporocysts. In spite of the fact that the name Microphallus pseudopygmaeus is widespread in special literature, the original description of this species (Galaktionov, 1980) was performed in contravention of the International Code of Zoological Nomenclature. This article is aimed to correct the above defect. The maritae of Microphallus pseudopygmaeus were obtained from the common eider ducklings which were infected experimentally with metacercariae of Microphallus sp. I Galaktionov, 1980. These metacercariae were extracted from the naturally infected mollusks Littorina saxatilis collected at the Barents Sea coast. The valid description of the species M. pseudopygmaeus, its comparison with other representatives of the "pygmaeus" microphallids and synonymy are provided. Detailed analysis of digeneans from marine and coastal birds preserved in the collections of the Zoological Institute RAS (St. Petersburg, Russia) and the Natural History Museum (London, UK) showed that in some cases M. pseudopygmaeus was misidentified as M. pygmaeus. It has been shown that M. pseudopygmaeus has an amphiboreal-arctic distribution and the spectrum of its first intermediate hosts is unequally wide for digeneans. It includes 15 species of north-Atlantic and north-Pacific mollusks belonging to different families and even orders of Prosobranchia. At the same time, the range of final hosts of M. pseudopygmaeus is limited by benthophagous marine ducks, first of all the common eider.

Eucoleus contortus (Nematoda: Capillariidae), a parasite of Cairina moschata domestica (Anseriformes: Anatidae) on Marajó Island, Pará State, in Brazilian Amazon.

The family Capillariidae is one of the most important in the superfamily Trichinelloidea, with 27 genera and more than 300 species parasitizing vertebrates. This study considers the morphology, morphometry and prevalence of Eucoleus contortus parasitizing the Muscovy duck Cairina moschata domestica esophagus from Marajó Island, in State of Pará, Brazil. Morphologically the nematodes had a filiform body, with transversely striated cuticle, long esophagus, divided into two parts, one muscular and another consisting of stichocytes, spicule weakly sclerotized, spiny sheath and pseudobursa present in males. Females had a pre-equatorial vulva, barrel-shaped eggs and were bioperculated. In the northern region of Brazil, the Muscovy duck is an abundant bird, and one of the items in the food supply for human communities. The occurrence of E. contortus adds data to the biodiversity of parasites described in Anseriform birds of the Brazilian Amazon, especially those used as source of protein by human communities of Marajó.

Taxonomic structure of cestodofauna of two species of diving ducks Aythya fuligula and A. marila (Anseriformes: Aythyini) in north-western Poland

Diving ducks Aythyini Delacour et Mayr, 1945 are an interesting object of the parasitological studies because due to living in two environments (aquatic and terrestrial) and migrating over long distances, they can come into contact with many potential hosts for parasites. In the recent years, a decrease in the population of diving ducks has been observed, especially of the tufted duck and the scaup. Both of them remain the most common species found in the region of West Pomerania, so the presented research is limited to the parasitological studies of these two species of ducks. The aim of this study was to determine the taxonomic structure of the cestodofauna of two species of diving ducks, the tufted duck and the scaup, wintering in north-west Poland. The research material consisted of 14,734 tapeworms collected from digestive tracts of 256 birds, 174 tufted ducks Aythya fuligula (Linnaeus, 1758) and 82 scaups A. marila (Linnaeus, 1761). All identified tapeworms obtained from digestive tracts of the hosts belonged to the Hymenolepididae family (order Cyclophyllidea). A total of 25 species of 9 genera were identified in the cestodofauna of the tufted duck, while in the cestodofauna of the scaup: 12 species of 7 genera. During 10 years of studies out of all of the 26 recorded species, 6 have been found in Poland for the first time. Moreover, 13 new, unlisted parasite-host relationships have been identified: 7 in the digestive tract of the tufted duck and 6 in the scaup.