Parasites Of Birds Research Articles

Unravelling the diversity of Posthodiplostomum Dubois, 1936 (Trematoda: Diplostomidae) in fish-eating birds from the Neotropical region of Mexico, with the description of a new species

Abstract Adults of the genus Posthodiplostomum, Dubois, 1936 are parasites of fish-eating birds, mainly of the family Ardeidae, and are globally distributed. The genus currently comprises 35 species, although recent molecular evidence has shown that the diversity of the genus is underestimated since several candidate species have been recognized. In the Neotropical region of Mexico, at least 6 Posthodiplostomum lineages have been detected with metacercaria stages recovered from unrelated fish hosts. Here, we obtained adult specimens of Posthodiplostomum from 6 fish-eating birds representing 2 families (Butorides virescens, Ardea herodias, Nycticorax nycticorax, Tigrisoma mexicanum – Ardeidae, and Rynchops niger and Leucophaeus atricilla – Lariidae) from 4 localities in southern Mexico. Specimens were sequenced for 2 nuclear (28S and ITS1–5.8S–ITS2) and 1 mitochondrial (cox1) molecular marker. Phylogenetic analyses allowed us to link metacercariae and adult specimens and recognized a lineage, which was described morphologically. The new species can be distinguished from its congeners by its prosoma morphology and body size; this is the first described species in the Neotropical region of Mexico. Additionally, new host and locality records for P. macrocotyle and P. pricei are presented, expanding their geographical distribution range in the Americas.

Platyhelminthes of common buzzard (Buteo buteo): Checklist of species in Europe and new parasite-host associations in Romania

BackgroundPlatyhelminthes are common parasites of diurnal birds of prey, including common buzzard (Buteo buteo). They are widely distributed in Europe. Despite the extensive study of flatworms across the continent, this study represents the first report for Romania and extends the biogeographic knowledge of Platyhelminthes in diurnal raptors. It also identifies common buzzards as a new host of Parastrigea flexilis in Europe. Materials and methodsBetween 2017 and 2020, 63 common buzzards (Buteo buteo) found road killed or dead due to other causes were collected from Romania. All specimens were necropsied and examined for internal helminths, which were preserved in ethanol for molecular identification and formaldehyde for morphological identification. ResultsSpecies identified included Cestoda: Cladotaenia globifera (33.3%) and five species of Trematoda: Neodiplostomum attenuatum (12.7%), Strigea falconis (6.4%), Parastrigea flexilis (3.2%), Neodiplostomum spathoides (3.2%) and Brachylaima fuscata (1.6%). ConclusionsThis study provides new data about diversity, phylogenetics and geographical distribution of Platyhelminthes parasitizing Buteo buteo in Romania. To our best knowledge, it identifies B. buteo as a new host of Parastrigea flexilis and reports the first genetic sequence of Neodiplostomum spathoides.

Common cuckoo eggs are more resistant to puncture by the host

The puncture resistance hypothesis suggests that thick-shelled eggs of parasitic birds can resist puncture-ejection by the host. However, few experiments have yet been conducted to test this hypothesis in terms of natural host behavior (e.g., pecking at foreign eggs). To explore whether the eggshells of common cuckoos (Cuculus canorus) are resistant to puncture-ejection by their common hosts, Oriental reed warblers (Acrocephalus orientalis), we designed experiments to investigate if and how breeding Oriental reed warblers peck at foreign eggs that includes common cuckoo, Oriental reed warbler and budgerigar (Melopsittacus undulatus) eggs. The results showed that, given the same frequency of egg pecking, the probability of eggshell breakage was 87.5% for eggs of the Oriental reed warbler and 0% for eggs of the common cuckoo, with a significant difference (P = 0.001, Fisher's exact test). Our study shows clearly that common cuckoos' eggshells are less susceptible to puncture-ejection than those of Oriental reed warblers and budgerigars. This indicates that the eggshells of common cuckoos can resist host Oriental reed warblers' puncture-ejection, supporting the puncture resistance hypothesis.

Diversity and Interactions between Picobiine Mites and Starlings.

The subfamily Picobiinae (Acariformes: Syringophilidae) comprises obligate and permanent parasites of birds found exclusively in the quills of contour feathers. We studied associations of picobiine mites with birds of the family Sturnidae (Aves: Passeriformes) across the Palaearctic, Afrotropical, Oriental, and Oceanian zoogeographical regions. Among the 414 examined bird individuals belonging to 44 species (35.2% of all sturnids), 103 individuals from 24 species (54.5% of examined species) were parasitised by quill mites. The diversity of mites was represented by five species, including one newly described, Picobia malayi Patan and Skoracki sp. n. Statistical analysis of the Picobiinae-Sturnidae bipartite network demonstrated a low connectance value (Con = 0.20) and high modularity, with significant differences in the H2' specialisation index compared to null model values. The network structure, characterised by four distinct modules, highlighted the specificity and limited host range of the Picobiinae-Sturnidae associations. The distribution of Picobia species among starlings was congruent with the phylogeny of their hosts, with different mites parasitising specific clades of starlings. Additionally, the findings suggest that the social and breeding behaviours of starlings influence quite a high prevalence. Finally, our studies support the validity of museum collections to study these parasitic interactions.

Survey of gastrointestinal coccidian parasites of pet birds in Tehran

ABSTRACT Birds of various families and genera comprise a notable proportion of veterinary clients in veterinary practice. Regarding the scarcity of information on avian coccidia in pet birds, this study was designed to investigate and identify the diversity of gastrointestinal coccidian protozoa in caged pet birds. Accordingly, droppings samples were collected in 2.5% potassium dichromate and examined for the presence of oocysts by wet smear and by flotation with the saturated salt solution. Detected oocysts were further morphologically specified. Special Modified Ziehl-Neelsen stain was used for the detection of Cryptosporidium spp. oocysts. Out of the 145 droppings that were collected for parasitological investigations, it was discovered that a Japanese quail (Coturnix japonica) had a Cryptosporidium sp. infection (1/145: 0.7%). Additionally, Isospora spp. was found in a common mynah and a canary (2/145: 1.4%), while Eimeria sp. was detected in a canary (1/145: 0.7%). Studied birds were clinically normal and no signs of intestinal infection were observed. The oocysts are described morphologically in detail and compared with the available data. Periodic faecal examination should be recommended for monitoring intestinal parasites in pet birds both from a public health perspective for Cryptosporidium and for avian host health in the case of non-zoonotic parasites. Additionally, the identification of parasite/host species composition will enhance our understanding of species diversity and the variety of hosts that coccidian parasites are capable of infecting.

Haemosporidian intensity and nestlings' life-history along an urban-to-rural gradient

Urban areas, i.e. dense housing and reduced green spaces, can significantly impact avian health, through altering land use and increasing biotic and abiotic stress. This study assessed the association of urbanization on haemosporidian infections, vectors, immune response, and body condition in Parus major nestlings, across four classes of urbanization along an urban-to-rural gradient in Vienna, Austria. Contrary to our expectations, vector abundance remained consistent across the gradient, while an increase in leukocyte count is positively associated with total parasite intensity. We found that nestlings in more urbanized areas exhibited higher parasite intensity and altered immune response, as evidenced by variations in the heterophil to lymphocyte ratio and leukocyte counts. Culicidae female vectors were associated with nestlings’ total parasites, scaled mass index, and industrial units. Nestlings in highly developed areas had higher infection rates than those in forests, suggesting increased exposure to infections. However, there was no clear relationship between total female vectors and total parasites. The level of urbanization negatively affected nestling body condition, with a decrease in fat deposits from forested to highly urbanized areas. Our findings highlight the complex interplay between urbanization, vector-borne parasite transmission, and host immune response, emphasizing the need for comprehensive urban planning to improve wildlife health and guarantee ecosystem functioning. Understanding how urbanization affects bird immunity and parasite infections is critical for adapting urban landscapes for wildlife health and ecosystem integrity.

Avian nematode parasites of some wild birds of Bangladesh

Avian nematode parasites of some wild birds of Bangladesh

Urban house finches are more resistant to the effects of artificial light at night

Rapid urbanization of habitats alters the physical, chemical, auditory, and photic environments of human and wild animal inhabitants. One of the most widespread transformations is caused by artificial light at night (ALAN), but it is not clear the extent to which individuals acclimate to such rapid environmental change. Here, we tested the hypothesis that urban birds show increased resistance to harmful behavioral, parasitological, and physiological effects of ALAN. We captured house finches (Haemorhous mexicanus), a bird that commonly inhabits cities and their natural surroundings, from two urban and two rural sites in Phoenix, Arizona, USA, which differ by both degree of urbanization and by multiple orders of magnitude in ALAN intensity, and placed them in a common garden laboratory setting. We exposed half of the birds from each habitat type to ecologically relevant levels of night lighting during the subjective night and found that, while ALAN exposure reduced sleep in both urban and rural birds, ALAN-exposed urban birds were able to sleep longer than ALAN-exposed rural birds. We also found that ALAN exposure increased the proliferation rate of an intestinal coccidian parasite (Isospora spp.) in both urban and rural birds, but that the rate of proliferation was lower in urban relative to rural birds. We found that night lighting suppressed titers of feather corticosterone in rural but not urban birds, suggesting that light impairs HPA function through chronic stress or suppression of its circadian rhythmicity, and that urban birds were again resistant to this effect. Mediation analyses show that the effect of ALAN exposure in rural birds was significantly sleep-mediated for feather corticosterone but not coccidiosis, suggesting a diversity of mechanisms by which ALAN alters physiology. We contribute further evidence that animals from night-lit habitats can develop resistance to ALAN and its detrimental effects.

New insights into the relationship of parasitic quill mites and birds: Picobia species in Asian and New World Barbets

Quill mites are obligatory parasites of birds, widely distributed among their hosts. For the first time, we examined birds from two small, phylogenetically closely related piciform families, Megalaimidae (New World Barbets) and Capitonidae (Asian Barbets), for infestation by parasitic mites of the subfamily Picobiinae (Acariformes: Syringophilidae). Birds of the family Megalaimidae were infested by two new species of the genus Picobia: Picobia insolita Skoracki, Sikora & Unsoeld n. sp. collected from Caloramphus hayii in Indonesia, and Picobia paraheeri Skoracki, Sikora & Unsoeld n. sp. found on nine bird species of the genus Psilopogon, including P. zeylanicus in Sri Lanka, P. asiaticus in India, P. virens in China, P. franklini and P. lineatus both in Nepal, and P. corvinus, P. rafflesii, P. chrysopogon, P. pyrolophus, all in Indonesia. Within the Capitonidae family, a single quill mite species, Rafapicobia olszanowskii Skoracki et al. 2020, was found infesting two species of the genus Capito, i.e. C. maculicoronatus in Panama and C. niger in Surinam and Guyana, and these two Asian Barbet species are new hosts for this quill mite species. Our further analysis of picobiine mite records associated with the entire order of Piciformes revealed a correlation between the mites’ distribution patterns and the phylogeny of piciform birds. This significant congruence suggests a close evolutionary relationship between picobiine mites and their avian hosts. http://zoobank.org/urn:lsid:zoobank.org:pub:F9DEB980-6481-4229-A071-52AC9FF69879 http://zoobank.org/urn:lsid:zoobank.org:act:6B4F98EB-D166-4DBF-B26F-49F4B22903A8 http://zoobank.org/urn:lsid:zoobank.org:act:98140DAC-5C53-438B-85A6-1FBA52D178D0

Morphological and molecular data on acuariid nematodes in European great cormorants (Phalacrocorax carbo sinensis) and pygmy cormorants (Microcarbo pygmaeus)

The family Acuariidae is a speciose group of parasitic nematodes, infecting mostly birds as definitive hosts. This study focused on the characterization of two species of acuariids, collected in two different species of piscivorous birds, the European great cormorant Phalacrocorax carbo sinensis from Italy, and the pygmy cormorant Microcarbo pygmaeus from Israel. Parasites were analyzed using light and scanning electron microscopy and by amplification and sequencing of the 28S rDNA. The results of morphological and molecular analyses showed that Ph. carbo sinensis was infected by the acuariid Syncuaria squamata (12 females) and Cosmocephalus obvelatus (1 female), whereas M. pygmaeus was infected by C. obvelatus (2 males, 12 females). The present results provide new data on the distribution of acuariid parasites of piscivorous birds, the first report of Acuariidae in Israel, and the first molecular data on S. squamata and C. obvelatus, which will be useful in future epidemiological and phylogenetic studies of these widely distributed, but less molecularly studied parasites.

"Isolation by Gentes with Asymmetric Migration" shapes the genetic structure of the common cuckoo in China.

Amid coevolutionary arms races between brood parasitic birds and their diverse host species, the formation of host-specific races, or gentes, has drawn significant research focus. Nevertheless, numerous questions about gentes evolutionary patterns persist. Here, we investigated the potential for gentes evolution across multiple common cuckoo (Cuculus canorus) populations parasitizing diverse host species in China. Using maternal (mitochondrial and W-linked DNA) and biparental (autosomal and Z-linked DNA) markers, we found consistent clustering of cuckoo gentes (rather than geographical populations) into distinct clades in matrilineal gene trees, indicating robust differentiation. In contrast, biparental markers indicated intermixing of all gentes, suggesting asymmetric gene flow regardless of geography. Unlike the mitonuclear discordance commonly resulting from incomplete lineage sorting, adaptive introgression, or demographic disparities, the observed pattern in brood parasitic cuckoos might reflect biased host preferences between sexes. We hereby present the "Isolation by Gentes with Asymmetric Migration" model. According to this model, the maternal line differentiation of the common cuckoo in China is potentially driven by host preferences in females, whereas males maintained the integrity of the cuckoo species through random mating. To achieve this, cuckoo males could perform flexible migration among gentes or engage in early copulation with females before reaching the breeding sites, allowing female cuckoos to store sperm from various gentes. Future studies collecting additional samples from diverse cuckoo gentes with overlapping distribution and investigating the migratory and copulation patterns of each sex would enhance our understanding of sex-biased differentiation among cuckoo populations in China.

Gastrointestinal parasites in captive wild birds in Mineiros, Goiás, Brazil.

Studying parasites in captive wild birds is vital for their health, well-being, biodiversity preservation, species conservation, and safeguarding of both individual birds and ecosystems. It holds significance for public health by identifying potential zoonotic risks. We aimed to describe the occurrence of gastrointestinal parasites in captive wild birds from a Conservation Institute in Brazilian Cerrado biome. Fresh fecal samples were collected from 17 captive wild birds (Anodorhynchus hyacinthinus, Ara ararauna, Ara chloropterus, Ara macao, Megascops choliba, Pteroglossus castanotis, Ramphastos dicolorus, Ramphastos tucanus and Strix huhula) at a Conservation Institution in Mineiros, state of Goiás. The samples were processed for Willis' simple flotation and Hoffman's spontaneous sedimentation examinations to identify parasitic forms of gastrointestinal endoparasites. Macaw aviary birds (Ar. ararauna, Ar. chloropterus and Ar. macao) showed higher positivity, with all six fecal samples positive for helminths or protozoa. In contrast, captive toucans showed only two positive results (P. castanotis and R. dicolorus). An. hyacinthinus showed Ascarididae, Capillarinae and Trematoda eggs; whereas S. huhula had Ascarididae eggs. Regular parasitological examinations are essential for the timely detection and treatment of gastrointestinal infections in captive birds, thereby enhancing overall bird management.

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.

Morphological and molecular identification of Sarcocystis falcatula from the emerald toucanet (Aulacorhynchus albivitta) in Colombia

Sarcocystis spp. are cyst-forming coccidia characterized by a two-host predator-prey life cycle. Sarcocysts are formed in muscles or nervous system of the intermediate host, while sporocysts develop in the small intestine of the definitive host. The intermediate hosts of Sarcocystis falcatula are wild birds. Colombia is one of the countries with the greatest biodiversity of birds, however, there are few studies related to this parasite in wild birds. This study presents the morphological and molecular detection of Sarcocystis falcatula collected from the emerald toucanet (Aulacorhynchus albivitta), a wild bird species endemic to South America. Pectoral muscle samples were obtained, and microscopic and molecular detection was performed by light microscopy, transmission electron microscopy, and amplifying of the first internal transcribed spacer (ITS-1) and surface antigen-encoding genes (SAGs). Sarcocystis measured an average of 161 × 42 μm, with a cyst wall ∼0.4 μm thick. Ultrastructurally, the sarcocyst wall type 11b-like consisted of numerous villar protrusions of 850 nm wide on average. The ITS-1 sequence showed 97.0–99.7% identity to S. falcatula previously described from birds in the United States and Brazil, respectively. Concatenated phylogenetic analysis based on SAG2, SAG3 and SAG4 confirmed that the new isolate is grouped with other sequences of Sarcocystis from South America, but divergent from those isolates obtained in North America. The results of this study demonstrate for the first time the presence of S. falcatula in a wild bird from Colombia.

Contributions to our knowledge on avian louse flies (Hippoboscidae: Ornithomyinae) with the first European record of the African species Ornithoctona laticornis

BackgroundLouse flies (Diptera, Hippoboscidae) are important blood-sucking parasites of birds and mammals with a worldwide distribution. The aim of our study was to collect louse flies from birds across multiple sites in Hungary and evaluate the effects of avian traits on louse fly–host relationships.MethodsBetween 2015 and 2022, 237 louse flies were collected from birds at multiple locations in Hungary. The louse flies were identified to species level by morphological and molecular methods. Louse fly species and their seasonal dynamics were analyzed.ResultsSix louse fly species were identified: Ornithomya avicularia, Ornithomya fringillina, Ornithomya biloba, Ornithomya chloropus, Ornithoica turdi and Ornithoctona laticornis. Results of statistical analyses indicated that habitat, migration habits and the feeding places of birds have significant effects on their possible role as hosts of O. avicularia, O. fringillina and O. turdi. Analysis of the temporal distribution of avian louse flies showed different seasonal patterns according to species. Phylogenetic analyses highlighted that O. turdi clustered separately from other members of the subfamily Ornithomyinae which thus did not form a monophyletic group.ConclusionsThis study presents one of the longest continuous collections of ornithophilic louse fly species in Europe so far. Avian traits were shown to influence louse-fly infestation. To our best knowledge, this is the first report on O. laticornis in Europe. The ability of this African louse fly species to survive in Europe, as demonstrated in the present study, may be an indication of its future establishment. Our findings, in accordance with previous reports, also indicated that the subfamily Ornithomyinae should be taxonomically revised.Graphical

Enteroparasites and risk factors for infection in native and exotic domiciled birds in the North Pioneer region of Paraná State, Brazil

Although parasitic infections are common in free-ranging birds, they pose more significant threats in captivity. Free-ranging birds can live in large areas and have low exposure to parasitosis. On the other hand, birds kept in captivity, the high population density results in greater exposure, putting the animal's survival at risk. The aim of this study was to assess the occurrence of gastrointestinal endoparasites in domiciled birds (native and exotic) in the Mesoregion North Pioneer of Paraná. For this, 59 fecal samples were collected from 63 birds and analyzed by the centrifugation-flotation method in hypersaturated sucrose solution. Of the 63 birds, 38 (60%) were native, 22 (35%) exotic and 3 (5%) hybrids. Oocysts, eggs and larvae were found in 22.03% (13/59) of the samples analyzed. Higher occurrence of protozoa (20.34% - 12/59) than helminths (5.08% - 3/59) was observed, in which seven genera found: Isospora, Eimeria, Ancylostoma, Heterakis, Strongyloides, Cryptosporidium and one cestode. No endoparasites were found in the ten exotic birds and three native birds analyzed. It is concluded that the birds were infected by helminths and protozoa with a higher occurrence of coccidia, with the genus Isospora predominating. Probably due to the low sampling, there was no influence of keeping birds in individual cages compared to birds kept in collective cages, birds raised in rural or urban areas, nor of the adequacy and hygiene of drinkers and feeders, thermal comfort and hygiene of the birds' enclosures. Studies on parasites in wild birds are necessary to gain a more profound understanding of the intensity of anthropogenic influences on these animal species.

Protozoan parasites of birds from the Tremembé formation (Oligocene of the Taubaté Basin), São Paulo, Brazil

ObjectiveTo analyze the presence of protozoan parasites in bird coprolites from the Tremembé Formation (Oligocene of the Taubaté Basin). MaterialsTwenty avian coprolites embedded in pyrobituminous shale matrices. MethodsSamples were rehydrated and subjected to spontaneous sedimentation. ResultsPaleoparasitological analyses revealed oocysts compatible with the Eimeriidae family (Apicomplexa) and one single Archamoebae (Amoebozoa) cyst. ConclusionsThe present work increases the amount of information about the spread of infections throughout the Cenozoic Era and reveals that the Brazilian paleoavifauna played an important role in the Apicomplexa and Amoebozoa life cycles. SignificanceThis is the first record of protozoans in avian coprolites from the Oligocene of Brazil. These findings can help in the interpretation of phylogenies of coccidian parasites of modern birds, as certain taxonomic characters observed in the Oligocene Protozoa characterize monophyletic groups in current molecular phylogenetic analyses. LimitationsNone of the oocysts were sporulated; therefore, it is not possible to identify the morphotypes to genus or species. Suggestions for further researchOur results create new perspectives related to biogeographic studies of the parasitic groups described and may improve the understanding of the temporal amplitude of parasitic evolutionary relationships between Protozoans and birds.

Isospora and Lankesterella Parasites (Eimeriidae, Apicomplexa) of Passeriform Birds in Europe: Infection Rates, Phylogeny, and Pathogenicity.

Wild birds are common hosts to numerous intracellular parasites such as single-celled eukaryotes of the family Eimeriidae (order Eucoccidiorida, phylum Apicomplexa). We investigated the infection rates, phylogeny, and pathogenicity of Isospora and Lankesterella parasites in wild and captive passerine birds. Blood and tissue samples of 815 wild and 15 deceased captive birds from Europe were tested using polymerase chain reaction and partial sequencing of the mitochondrial cytochrome b and cytochrome c oxidase I and the nuclear 18S rRNA gene. The infection rate for Lankesterella in wild birds was 10.7% compared to 5.8% for Isospora. Chromogenic in situ hybridization with probes targeting the parasites' 18S rRNA was employed to identify the parasites' presence in multiple organs, and hematoxylin-eosin staining was performed to visualize the parasite stages and assess associated lesions. Isospora parasites were mainly identified in the intestine, spleen, and liver. Extraintestinal tissue stages of Isospora were accompanied by predominantly lymphohistiocytic inflammation of varying severity. Lankesterella was most frequently detected in the spleen, lung, and brain; however, infected birds presented only a low parasite burden without associated pathological changes. These findings contribute to our understanding of Isospora and Lankesterella parasites in wild birds.

Enigmatic host-mite relationships: Unraveling the distribution of quill mites on Birds-of-Paradise

Mites of the family Syringophilidae (Acariformes: Prostigmata: Cheyletoidea) are permanent and obligatory parasites of birds. This study presents an analysis of mite material collected from 22 avian species belonging to the family Paradisaeidae (Passeriformes), revealing the presence of four mite species belonging to four genera: Syringophiloidus attenboroughi n. sp., Peristerophila regiusi n. comb., Picobia frankei, and Gunabopicobia garylarsoni. In the present work, the genus Neoperisterophila is synonymized with the genus Peristerophila. While the genera Syringophiloidus and Picobia were expectedly found on paradisaeid birds, given their prevalence in passerines, the presence of Peristerophila and Gunabopicobia was intriguing, suggesting potential host-switching events. The specificity of these mites varies, with some showing occurrence on hosts of closely related genera and others infesting phylogenetically distant hosts. Notably, the distribution of specific mite species on the Birds-of-Paradise appears to be influenced by both long coevolutionary histories and incidental contacts between often unrelated or intergeneric hybrid species of paradisaeid birds. Furthermore, our research of 104 specimens from 22 Birds-of-Paradise species shows generally low infestation rates across the studied species, suggesting a nuanced interaction between these mites and their avian hosts. Additionally, our network analysis provides a deeper understanding of these host-parasite interactions, revealing a high level of specialization and complexity in these ecological relationships.

Analyzing the safety of the parasiticide fungus Mucor circinelloides: first insights on its virulence profile and interactions with the avian gut microbial community.

Parasiticide fungi are considered an accurate, sustainable, and safe solution for the biocontrol of animal gastrointestinal (GI) parasites. This research provides an initial characterization of the virulence of the native parasiticide fungus Mucor circinelloides (FMV-FR1) and an assessment of its impact on birds' gut microbes. The genome of this fungus was sequenced to identify the genes coding for virulence factors. Also, this fungus was checked for the phenotypic expression of proteinase, lecithinase, DNase, gelatinase, hemolysin, and biofilm production. Finally, an in vivo trial was developed based on feeding M. circinelloides spores to laying hens and peacocks three times a week. Bird feces were collected for 3 months, with total genomic DNA being extracted and subjected to long-read 16S and 25S-28S sequencing. Genes coding for an iron permease (FTR1), iron receptors (FOB1 and FOB2), ADP-ribosylation factors (ARFs) (ARF2 and ARF6), and a GTPase (CDC42) were identified in this M. circinelloides genome. Also, this fungus was positive only for lecithinase activity. The field trial revealed a fecal microbiome dominated by Firmicutes and Proteobacteria in laying hens, and Firmicutes and Bacteroidetes in peacocks, whereas the fecal mycobiome of both bird species was mainly composed of Ascomycetes and Basidiomycetes fungi. Bacterial and fungal alpha-diversities did not differ between sampling time points after M. circinelloides administrations (P = 0.62 and P = 0.15, respectively). Although findings from this research suggest the lack of virulence of this M. circinelloides parasiticide isolate, more complementary in vitro and in vivo research is needed to conclude about the safety of its administration to birds, aiming at controlling their GI parasites.IMPORTANCEA previous study revealed that the native Mucor circinelloides isolate (FMV-FR1) can develop parasiticide activity toward coccidia oocysts, one of the most pathogenic GI parasites in birds. However, ensuring its safety for birds is of utmost importance, namely by studying its virulence profile and potential effect on commensal gut microbes. This initial study revealed that although this M. circinelloides isolate had genes coding for four types of virulence factors-iron permease, iron receptors, ADP-ribosylation factors, and GTPase-and only expressed phenotypically the enzyme lecithinase, the administration of its spores to laying hens and peacocks did not interfere with the abundances and diversities of their gut commensal bacteria and fungi. Although overall results suggest the lack of virulence of this M. circinelloides isolate, more complementary research is needed to conclude about the safety of its administration to birds in the scope of parasite biocontrol programs.