Prevalence, Infection Intensity and Molecular Diagnosis of Mixed Infections with Metastrongylus spp. (Metastrongylidae) in Wild Boars in Uzbekistan.

The aim of the present study was to characterize the diversity of Metastrongylus spp. in wild boars and the earthworm intermediate host species contributing to the maintenance of the life cycle. Here, wild boars were subjected to parasitological necropsies, and lungworm species were identified morphologically, followed by confirmation using ITS-2 sequencing and a phylogenetic analysis. Earthworms were collected from wild boar habitats and investigated for the presence of larvae. The prevalence of Metastrongylus spp. in wild boars was 78.8%, and many individuals were positive for all three detected species, Metastrongylus pudendotectus, Metastrongylus salmi and Metastrongylus elongatus. The phylogenetic analysis did not clearly resolve all species, except for M. pudendotectus. Age group and season had no influence on prevalence, while intensity was significantly higher in autumn than in spring and summer (Kruskal-Wallis followed by Dunn's test). Three out of six investigated earthworm species were positive for metastrongyloid larvae (prevalence of 10.4-16.7%), but neither their phylogenetic relationship nor ecological microhabitats were able to explain these differences. Further sequence data should be used to improve the resolution in phylogenetic trees to determine potential cryptic species in the genus, while the application of deep sequencing approaches might provide insights into species-specific epidemiology and pathology.

Morphological and ecological features of some nematodes of the genus Rhabdochona in marinka obtained from Fergana Valley, Uzbekistan.

The aim is to study the morphological and ecological features of some nematode species of the genus Rhabdochona parasites of marinka fish in the Fergana Valley, Uzbekistan. Rhabdochona gnedini, Rhabdochona denudata and Rhabdochona hellichi turkestanica were detected as 5.3%, 7.9% and 3.7%, respectively. According to the Authors' knowledge, Rh. hellichi turkestanica was recorded in Uzbekistan and Central Asian republics for the first time. Rhabdochona spp. were only detected in the intestine of marinkas lived in the mountain rivers Rezaksay, Chodaksay and small tributaries of the Syrdarya river in western Fergana. The prevalence of Rhabdochona spp. in the marinka can be associated with a wide range of nutrition in the mountain rivers and small tributaries of the Syrdarya river, where it could eat large numbers of mayfly and caddis larvae that act as intermediate hosts of rhabdochona.

Molecular phylogeny and diagnosis of species of the family Protostrongylidae from caprine hosts in Uzbekistan.

Protostrongylids are important pulmonary parasites of ungulates, particularly caprines. Their complex life cycles involve terrestrian gastropods as intermediate hosts. Morphological discrimination of larvae in feces and snails is impossible to the species level, and molecular data are missing for many species. To improve diagnosis and epidemiology of protostrongylids, this study describes internal transcribed spacer 2 (ITS-2) sequences for five protostrongylid and one metastrongylid species from Uzbekistan. Morphological and molecular analyses identified Protostrongylus rufescens, Protostrongylus hobmaieri, Protostrongylus sp., Spiculocaulus leuckarti, and Cystocaulus ocreatus. Sequence differences between ITS-2 were sufficient to allow species identification, e.g., in the Protostrongylinae intraspecific and interspecific genetic distances ranged between 0-0.01 and 0.05 and 0.16, respectively. There was one exception in the Elaphostrongylidae with identical ITS-2 sequences in Elaphostrongylus cervi and Elaphostrongylus rangiferi questioning their status as valid species. Maximum likelihood analysis sequences largely supported the currently assumed phylogenetic relationships among Protostrongylidae as predicted using morphological characters. The monophyly of the subfamilies Varestrongylinae, Elaphostrongylinae, and Protostrongylinae was corroborated with support values in Shimodaira-Hasegawa or Bayesian modifications of the approximate likelihood ratio test (aLRT) ≥97%, but support for Muellerinae was weak (8 and 52%, respectively) since Muellerius capillaris differs significantly from the other Muellerinae. On the genus level, paraphyly of the genus Protostrongylus was confirmed since the members of the genera Spiculocaulus and Orthostrongylus were located within the Protostrongylus cluster (aLRT ≥99%). Maximum likelihood unequivocally assigned every unique sequence to the correct species confirming suitability of ITS-2 regions for diagnosis protostrongylids except of E. cervi and E. rangiferi.