Caryospora neofalconis and other enteroparasites in raptors from Mexico

Helminth and ectoparasitic faunas of the Harris's hawk, Parabuteo unicinctus (Accipitriformes: Accipitridae), in Chile: new data on host-parasite associations for Neotropical raptors

Birds of prey harbor a wide spectrum of various parasites, mostly with a heteroxenous life cycle. However, most reports on their parasites come from Europe. Although the Harris's hawk (Parabuteo unicinctus) is a widespread species in America, parasitological surveys on this hawk are mostly focused on coprological findings and ectoparasites, with poor attention paid to helminths. The aim of this study was to gather new and additional data on host-parasite associations for the Harris's hawk. Twenty-nine birds from central and southern Chile were necropsied. Further, nine birds from a rehabilitation center and 22 museum specimens were inspected for ectoparasites. Sixty-eight percent of birds hosted at least one parasite species. Four lice species, one mite species and eight helminth species (five nematodes, two platyhelminthes and one acanthocephalan) were recorded. Parasitic lice Colpocephalum nanum and Nosopon chanabense, and a nematode Cyathostoma (Hovorkonema) americana were recorded for the first time in raptors from the Neotropics. A feather mite, Pseudalloptinus sp., nematodes, Physaloptera alata and Microtetrameres sp., and a trematode Neodiplostomim travassosi, were recorded for the first time in Chile. The presence of diverse heteroxenous helminths reported here in the Harris's hawk could be explained by the generalist diet of this raptor.

Prevalence and diversity of intestinal parasites in household and temple pigeons ( Columba livia ) in central Nepal

Background

Intestinal infection, caused by various protozoans and helminths, represents one of the significant health concerns in pigeons around the world.

Objectives

The present study aimed to determine the diversity and prevalence of the intestinal parasites in pigeons found in Ratnanagar Municipality, Chitwan, in central Nepal.

Methods

The fresh faecal samples (n = 155) were non‐invasively collected from different households and temples pigeons The individual samples were immediately preserved in the 2.5% potassium dichromate solution and transported to the research laboratory. Following direct wet mount and concentration methods, the samples were observed under a compound microscope.

Results

The results showed 87.1% prevalence rate with 16 parasite species that included 8 protozoan and 8 helminth faunae. The faecal samples of temple pigeons contained a higher prevalence rate with higher parasitic richness (95.6%; 16 species) than household pigeons (75.4%; 12 species). Mixed infection up to four different species was recorded in both types of sampling populations.

Conclusions

Pigeons harbour a greater prevalence and wider diversity of intestinal parasites and the parasitism varies based on the habitats. Proper management and effective deworming practices are recommended to control intestinal parasitic infection in these avian hosts.

The presence of pathogens and heavy metals in urban peregrine falcons (Falco peregrinus)

Background and Aim:

Wild birds raised in urban environments may be exposed to many negative factors, including biological and chemical toxic elements. The aim of the study was to assess the occurrence of bacteria and parasites in wild birds, based on the example of the peregrine falcon (Falco peregrinus) as a potential indicator of bacterial drug resistance genes. Toxicological contamination was also analyzed to determine the impact of urbanized areas on this predatory species, in terms of its health, welfare, and survival in urban environments.

Materials and Methods:

The samples consisted of down feathers and fresh feces obtained from seven falcon chicks (during obligatory veterinary examination) reared in two nests located in the Lublin region (Lublin and Puławy). Bacteria and parasites were isolated directly from feces by classical microbiological methods, polymerase chain reaction, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MS). The down feathers and feces of birds were used for toxicological testing by plasma inductively coupled plasma MS to assess the concentrations of selected heavy metals (cadmium [Cd], lead [Pb], arsenic [As], zinc [Zn], and copper [Cu]).

Results:

The study revealed the presence of a diverse microbiome in the falcon chicks, among which Escherichia coli, Enterococcus spp., and Staphylococcus spp. bacteria and parasites of the genus Caryospora were dominant. The presence of drug resistance genes was also confirmed among the pathogens. The toxicological analysis found high concentrations of toxic heavy metals, including Cd, Pb, As, and Zn, in the downy feathers and feces of peregrine chicks.

Conclusion:

Predatory free-living birds living in urban environments not only can be infected with various pathogens but may also show contamination with heavy metals, which could influence their natural resistance, condition, and welfare.

Detection of Eumonospora henryae (Apicomplexa: Sarcocystidae) from Falco columbarius (Falconiformes: Aves): Comparison of host-parasite phylogram and comments on the family Sarcocystidae Poche, 1913

The genus Eumonospora Allen, 1933 (Apicomplexa: Sarcocystidae), an avian coccidia, is characterized by monosporocystic and octasporozoic oocysts without Stieda and substieda bodies. Some members of Eumonospora, which infect several raptor species, exhibit high levels of pathogenicity, making eumonosporiosis the leading cause of death in captive-bred raptors. The host specificity of these species appears to be mesostenoxenous, as evidenced by unsuccessful transmission between different orders of avian hosts. However, several studies have detected Eumonospora spp. in taxonomically distant avian hosts, indicating that some of these species may be euryxenous. In the current study, diarrheic fecal examination of a captive-bred juvenile merlin (Falconiformes: Aves) in Tokyo, Japan, was conducted, and a large number of oocysts were morphologically and molecularly identified as E. henryae (Yakimoff and Matschulsky, 1932), a coccidia species reported only in Strigiformes. This is a new recorded host for this coccidia. Phylogenetic analyses via Bayesian inference and maximum likelihood methods using concatenated genomic datasets consisting of nuclear 18S rDNA, nuclear 28S rDNA and mitochondrial cytochrome C oxidase subunit 1 gene, revealed a well-supported monophyletic clade of Eumonospora spp. belonging to the family Sarcocystidae Poche 1913, which largely corresponded to the avian host phylogram. Therefore, based on distinguishable oocyst morphology, a new subfamily, Eumonosporinae, within the family Sarcocystidae, is proposed, and a reconsideration of the definition of Sarcocystidae is suggested. Further molecular characterization of this emerging pathogen, as well as clarification of its complete life cycle, including cyst-forming ability, is required for more appropriate generic assessment.

The emergence of Caryospora neofalconis in falcons in Central Saudi Arabia

Objective:

This study aimed to examine the occurrence of Caryospora (C.) neofalconis in falcons from the central region of the Kingdom of Saudi Arabia (KSA).

Materials and methods:

Fecal samples (n = 149) from 149 healthy falcons including 56 saker falcons (Falco cherrug), 13 lanner falcons (F. biarmicus), 18 peregrine falcons (F. peregrinus), 40 Barbary falcons (F. pelegrinoides), and 22 gyrfalcons (F. rusticolus) were collected between October 2018 and May 2019. The fecal samples were examined for the presence of C. neofalconis by microscopic examination followed by confirmation by polymerase chain reaction targeting 18S rRNA genes and their phylogenetic analyses.

Results:

The overall prevalence of C. neofalconis in the falcons was recorded as 10.7% (16/149) by microscopic examination. The highest prevalence was found in F. peregrinus (6/18, 33.3%), followed by F. rusticolus (3/22, 13.6%), F. cherrug (5/56, 8.9 %) and F. pelegrinoides (2/40, 5.0%). There was no C. neofalconis infection observed in F. biamicus. The 18S rRNA gene could be amplified in eight samples. The phylogenetic analysis of two C. neofalconis isolates exhibited a close relationship with the Mexican isolate (KT03081) with a 99.7% identity.

Conclusion:

To our knowledge, based on the microscopic and molecular analysis, this is the first report of C. neofalconis in F. cherrug, F. rusticolus, F. pelegrinoides, and F. peregrinus from the central region of the KSA and it emphasize the value of adopting preventive measures to limit the spread of C. neofalconis.

Molecular and morphological analysis of a Caryospora-like isolate (Apicomplexa: Eimeriidae) from the magpie-lark (Grallina cyanoleuca) (Latham, 1801) in Western Australia

A new Caryospora-like isolate is described from a magpie-lark (Grallina cyanoleuca) in Western Australia. Sporulated oocysts of the Caryospora-like isolate (n = 35) are subspherical with a shape index of 1.13 ((21.5 (19.7-23.6) × 19.0 (18.1-19.8) μm). The bilayered oocyst wall is smooth. Micropyle, polar granule and oocyst residuum are absent. The sporocyst is ellipsoidal, 18.9 (17.2-20.8) × 12.3 (11.9-12.8) μm, with a shape index (length/width) of 1.54. The sporocyst wall is bilayered. Stieda and substieda bodies are present, the Stieda body is small and flattened and the substieda is trapezoidal. Sporocyst with eight sporozoites arranged head to tail. The sporozoites are vermiform, 18.9 (17.2-20.8) × 12.3 (11.9-12.8) μm and have striations at the anterior end. Each sporozoite has both anterior and posterior refractile bodies. A sporocyst residuum is present. Molecular characterization of the isolated Caryospora-like oocysts was conducted at the 18S ribosomal RNA and the mitochondrial cytochrome oxidase (COI) loci. At the 18S rRNA locus, the Caryospora-like isolate exhibited 88.8% to 96.5% similarity with other Caryospora spp. from different hosts. At the COI locus, it showed 91.5% similarity to Caryospora cf. bigenetica JB-2013 (KF859856) from the rattlesnake, Sistrurus catenatus.

Caryospora-Like Coccidia Infecting Green Turtles (Chelonia mydas): An Emerging Disease With Evidence of Interoceanic Dissemination

Protozoa morphologically consistent with Caryospora sp. are one of the few pathogens associated with episodic mass mortality events involving free-ranging sea turtles. Parasitism of green turtles (Chelonia mydas) by these coccidia and associated mortality was first reported in maricultured turtles in the Caribbean during the 1970s. Years later, epizootics affecting wild green turtles in Australia occurred in 1991 and 2014. The first clinical cases of Caryospora-like infections reported elsewhere in free-ranging turtles were from the southeastern US in 2012. Following these initial individual cases in this region, we documented an epizootic and mass mortality of green turtles along the Atlantic coast of southern Florida from November 2014 through April 2015 and continued to detect additional, sporadic cases in the southeastern US in subsequent years. No cases of coccidial disease were recorded in the southeastern US prior to 2012 despite clinical evaluation and necropsy of stranded sea turtles in this region since the 1980s, suggesting that the frequency of clinical coccidiosis has increased here. Moreover, we also recorded the first stranding associated with infection by a Caryospora-like organism in Hawai'i in 2018. To further characterize the coccidia, we sequenced part of the 18S ribosomal and mitochondrial cytochrome oxidase I genes of coccidia collected from 62 green turtles found in the southeastern US and from one green turtle found in Hawai'i. We also sequenced the ribosomal internal transcribed spacer regions from selected cases and compared all results with those obtained from Caryospora-like coccidia collected from green turtles found in Australia. Eight distinct genotypes were represented in green turtles from the southeastern US. One genotype predominated and was identical to that of coccidia collected from the green turtle found in Hawai'i. We also found a coccidian genotype in green turtles from Florida and Australia with identical 18S and mitochondrial sequences, and only slight inter-regional differences in the internal transcribed spacer 2. We found no evidence of geographical structuring based on phylogenetic analysis. Low genetic variability among the coccidia found in green turtle populations with minimal natural connectivity suggests recent interoceanic dissemination of these parasites, which could pose a risk to sea turtle populations.

Caryospora peneireiroi n. sp. (Apicomplexa: Eimeriidae) in the common kestrel, Falco tinnunculus (Falconiformes: Falconidae), in mainland Portugal

The common kestrel Falco tinnunculus Linnaeus, 1758, is a widespread raptor, native in Europe, Asia and Africa, and vagrant in the Americas. In the current work, 27 fecal samples were collected from common kestrels kept in the Lisbon Center for Wild Animal Recovery, located at Monsanto Forest Park, Lisbon, Portugal. Five (19%) of them were found to be passing an undescribed species of Caryospora in their feces. The oocysts of Caryospora peneireiroi n. sp. were ellipsoidal with a bilayered wall and measured 47.1 × 37.6 µm with a shape index of 1.25. No micropyle, oocyst residuum or polar granule was present. The sporocysts were subspherical, measuring 25.1 × 24.3 µm. Stieda, sub-Stieda and para-Stieda bodies were absent. The sporocyst residuum was composed of many homogenous globules scattered throughout the periphery of the sporocyst. This is the fourth caryosporan species reported from F. tinnunculus.