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Eimeria is an important coccidian enteric parasite that infects a wide range of hosts and can cause substantial economic losses in the poultry and livestock industries. It is common for multiple Eimeria species to infect individual hosts, and this can make species identification difficult due to morphological similarities between species and mixed chromatograms when using Sanger sequencing. Relatively few studies have applied next-generation amplicon sequencing (NGS) to determining the genetic diversity of Eimeria species in different hosts. The present study screened 408 faecal samples from a range of hosts including livestock and wildlife using a previously developed quantitative polymerase chain reaction (qPCR) at the 18S locus and conducted amplicon NGS on the positives using a ~ 455-bp fragment of the 18S locus. A total of 41 positives (10.1%) were identified by qPCR from various hosts and NGS was successful for 38 of these positives. Fifteen Eimeria species and three genotypes were detected by NGS: E. ferrisi, E. kanyana, E. potoroi, E. quokka, E. setonicis, E. trichosuri, E. reichenowi, E. angustus, E. ahsata, E. auburnensis, E. bovis, E. brasiliensis, E. christenseni, E. crandallis, E. ovinoidalis, Eimeria sp. (JF419345), Eimeria sp. (JF419349) and Eimeria sp. (JF419351). Mixed infections were detected in 55.3% (21/38) of positive samples. The most striking finding was the identification of the same species in different hosts. This could be due to contamination and/or mechanical transmission or may provide support for previous studies suggesting that Eimeria species can infect not just closely related hosts but different genera and further research is required. This is also the first study to audit Eimeria populations in livestock (sheep and cattle) by NGS and could be applied in the future to determine the extent of pathogenic species and outcomes of Eimeria control strategies. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The present study assessed the prevalence and morphology of Leucocytozoon podargii from wild tawny frogmouths (Podargus strigoides) in Western Australia (WA) and genetically characterised the cytochrome b gene (cyt b) of L. podargii in wild tawny frogmouths from WA and Queensland (QLD). The prevalence of L. podargii in wild tawny frogmouths from WA was 93.3% (14/15; 95% CI, 68.1–99.8%). The morphological characters of L. podargii from WA were similar to L. podargii from QLD: the gametocytes were round-oval shape, approximately 8–12 μm in diameter; the macrogametocytes were 12.4 μm in diameter; microgametocytes were 10.4 μm in diameter; and the ratio of macrogametocytes and microgametocytes was 3:2. Sequence analysis of partial cyt b gene fragments revealed that L. podargii sequences isolated from wild tawny frogmouths in WA shared the highest similarity (99.8% at nucleotide level and 100% at protein level) with L. podargii isolated from wild tawny frogmouths in QLD. The mitochondrial 18S rRNA gene of L. podargii gametocytes was quantified using droplet digital PCR (ddPCR), and the highest gametocyte load was detected in the lung. This finding corresponds to the results of the histological study. Based on the morphological and molecular studies, it was concluded that the Leucocytozoon parasite identified from wild tawny frogmouths in WA is consistent with L. podargii from wild tawny frogmouths in QLD, and the present study has genetically characterised two different L. podargii genotypes (QLD and WA) for the first time. [ABSTRACT FROM AUTHOR]

A new Isospora (Apicomplexa:Eimeriidae) species is described from a silvereye (Zosterops lateralis) in Western Australia. Sporulated oocysts of this species are spherical, 24.2 (23.1-25.2) × 23.3 (22.8-23.9) μm, with a shape index (length/width) of 1.02, and with a smooth bi-layered oocyst wall, 1.2 μm thick (outer layer 0.9 μm, inner 0.3 μm). A polar granule is present, but the oocyst residuum and a micropyle are absent. The ovoid-shaped sporocysts are 16.1 (15.7-17.3) × 10.5 (15.7-17.3) μm and have a shape index of 1.53. A hemidome-shaped Stieda and a rectangular-shaped substieda body are present. A sporocyst residuum is present and composed of numerous granules of different sizes scattered among the sporozoites. The oocysts from this isolate are morphologically different from those of all known Isospora spp. This coccidian parasite was molecularly characterised at the 18S, 28S ribosomal RNA and the mitochondrial cytochrome oxidase (COI) gene. At the 18S locus, based on 1210 bp of sequence, this new isolate exhibited 99.9, 99.8, 99.7 and 99.5% similarity to I. sp. MAH-2013a (KF648870) from a superb starling (Lamprotornis superbus) in Canada, I. sp. MS-2003 (AY33157) from a Southern cape sparrow (Plocepasser mahali) in America, I. sp. Tokyo (AB75786) from Japan and I. sp. respectively. Further analysis of a subgroup of 300 bp long 18S sequences (n = 11), including I. anthochaerae and the other three Isospora characterised from birds in Western Australia, revealed that I. butcherae n. sp. exhibited 98.3% similarity to both I. sp. MAH-2013a (KF648870) and I. MS-2003 (AY33171). At the 28S locus, this new isolate exhibited 97.3% similarity with I. sp. MS-2003 from a California towhee (Melozone crissalis). At the COI locus, this new isolate exhibited 99.8% similarity to I. neochmiae from a red-browed finch. Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora butcherae n. sp. after Mrs. June Butcher for her lifelong dedication as a wildlife rehabilitator.ᅟ [ABSTRACT FROM AUTHOR]