A new tool for the molecular identification of Culicoides species of the Obsoletus group: the glass slide microarray approach

Ceratopogonidae are small nematoceran Diptera with a worldwide distribution, consisting of more than 5400 described species, divided into 125 genera. The genus Culicoides is known to comprise hematophagous vectors of medical and veterinary importance. Diseases transmitted by Culicoides spp. Such as African horse sickness virus, Bluetongue virus, equine encephalitis virus (Reoviridae) and Schmallenberg virus (Bunyaviridae) affect large parts of Europe and are strongly linked to the spread and abundance of its vectors. However, Culicoides surveillance measures are not implemented regularly nor in the whole of Austria. In this study, 142 morphologically identified individuals were chosen for molecular analyses (barcoding) of the mitochondrial cytochrome c oxidase subunit I gene (mt COI). Molecular analyses mostly supported previous morphologic identification. Mismatches between results of molecular and morphologic analysis revealed three new Culicoides species in Austria, Culicoides gornostaevae Mirzaeva, 1984, which is a member of the Obsoletus group, C. griseidorsum Kieffer, 1918 and C. pallidicornis Kieffer, 1919 as well as possible cryptic species. We present here the first Austrian barcodes of the mt COI region of 26 Culicoides species and conclude that barcoding is a reliable tool with which to support morphologic analysis, especially with regard to the difficult to identify females of the medically and economically important genus Culicoides.

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Culicoides species composition and molecular identification of host blood meals at two zoos in the UK

Parasites & Vectors ◽

10.1186/s13071-020-04018-0 ◽

2020 ◽

Vol 13 (1) ◽

Cited By ~ 2

Author(s):

Marion E. England ◽

Paul Pearce-Kelly ◽

Victor A. Brugman ◽

Simon King ◽

Simon Gubbins ◽

...

Keyword(s):

Species Composition ◽

Molecular Identification ◽

Culicoides Species ◽

The Uk ◽

Host Blood ◽

Blood Meals

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Validation of an Effective Protocol for Culicoides Latreille (Diptera: Ceratopogonidae) Detection Using eDNA Metabarcoding

Insects ◽

10.3390/insects12050401 ◽

2021 ◽

Vol 12 (5) ◽

pp. 401

Author(s):

Yoamel Milián-García ◽

Lauren A. A. Janke ◽

Robert G. Young ◽

Aruna Ambagala ◽

Robert H. Hanner

Keyword(s):

Molecular Identification ◽

Molecular Detection ◽

Morphological Characteristics ◽

Species Level ◽

Morphological Identification ◽

Culicoides Species ◽

Nacl Solution ◽

Identification Method

eDNA metabarcoding is an effective molecular-based identification method for the biosurveillance of flighted insects. An eDNA surveillance approach maintains specimens for secondary morphological identification useful for regulatory applications. This study identified Culicoides species using eDNA metabarcoding and compared these results to morphological identifications of trapped specimens. Insects were collected using ultraviolet (UV) lighted fan traps containing a saturated salt (NaCl) solution from two locations in Guelph, Ontario, Canada. There were forty-two Culicoides specimens collected in total. Molecular identification detected four species, C. biguttatus, C. stellifer, C. obsoletus, and C. mulrennani. Using morphological identification, two out of these four taxonomic ranks were confirmed at the species level (C. biguttatus and C. stellifer) and one was confirmed at the subgenus level (Avaritia [C. obsoletus]). No molecular detection of Culicoides species occurred in traps with an abundance of less than three individuals per taxon. The inconsistency in identifying Culicoides specimens to the species level punctuates the need for curated DNA reference libraries for Culicoides. In conclusion, the saturated salt (NaCl) solution preserved the Culicoides’ morphological characteristics and the eDNA.

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Variations in Surface Textures of Quartz Sand using Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069466 ◽

1970 ◽

Vol 28 ◽

pp. 494-495

Author(s):

Eugene J. Amaral

Keyword(s):

Electron Microscopy ◽

Glass Industry ◽

Glass Slide ◽

Distilled Water ◽

Early Paleozoic ◽

Secondary Effects ◽

Surface Textures ◽

High Silica ◽

Sand Deposit ◽

The U.S

Examination of sand grain surfaces from early Paleozoic sandstones by electron microscopy reveals a variety of secondary effects caused by rock-forming processes after final deposition of the sand. Detailed studies were conducted on both coarse (≥0.71mm) and fine (=0.25mm) fractions of St. Peter Sandstone, a widespread sand deposit underlying much of the U.S. Central Interior and used in the glass industry because of its remarkably high silica purity.The very friable sandstone was disaggregated and sieved to obtain the two size fractions, and then cleaned by boiling in HCl to remove any iron impurities and rinsed in distilled water. The sand grains were then partially embedded by sprinkling them onto a glass slide coated with a thin tacky layer of latex. Direct platinum shadowed carbon replicas were made of the exposed sand grain surfaces, and were separated by dissolution of the silica in HF acid.

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Electron microscopy in diagnostic virology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110702 ◽

1984 ◽

Vol 42 ◽

pp. 70-73

Author(s):

S. E. Miller

Keyword(s):

Electron Microscopy ◽

Tissue Culture ◽

Molecular Identification ◽

Point Of View ◽

Negative Stain ◽

Viral Diagnosis ◽

Electron Microscopist ◽

Diagnostic Virology

The techniques for detecting viruses are many and varied including FAT, ELISA, SPIRA, RPHA, SRH, TIA, ID, IEOP, GC (1); CF, CIE (2); Tzanck (3); EM, IEM (4); and molecular identification (5). This paper will deal with viral diagnosis by electron microscopy and will be organized from the point of view of the electron microscopist who is asked to look for an unknown agent--a consideration of the specimen and possible agents rather than from a virologist's view of comparing all the different viruses. The first step is to ascertain the specimen source and select the method of preparation, e. g. negative stain or embedment, and whether the sample should be precleared by centrifugation, concentrated, or inoculated into tissue culture. Also, knowing the type of specimen and patient symptoms will lend suggestions of possible agents and eliminate some viruses, e. g. Rotavirus will not be seen in brain, nor Rabies in stool, but preconceived notions should not prejudice the observer into missing an unlikely pathogen.

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