Genus Strongylus Research Articles

Intestinal Strongyle Genera in Different Typology of Donkey Farms in Tuscany, Central Italy

Intestinal strongyles are common helminths of donkeys, in which they may be responsible for disease and poor performance. This study aimed to identify intestinal strongyle genera in 55 naturally infected donkeys from three different farm typologies in Tuscany, central Italy, using morphological and metrical analysis of third stage larvae (L3) obtained from faecal cultures. Larvae were identified using two previous reported morphological identification keys. Moreover, eggs per gram (EPG) data were also evaluated to assess differences, if any, according to the farm typology, sex, and age of the examined donkeys. The results showed that small strongyles were prevalent in all donkey farms. In all examined farms, most (92–100%) of L3 were identified as cyathostomin species of the genera Cylicocyclus spp. and Cylicostephanus spp. Large strongyles of the genera Strongylus spp. and Triodontophorus spp., were identified at low percentage (8%), only in the single organic farm included in the study. A high agreement was observed between the two different morphometric keys used. No significant differences were found for EPG according to farm typology, and sex and age from the examined donkeys. This is the first report about genera identification of intestinal strongyles infecting donkeys in Tuscany, Italy.

The complete mitochondrial genome of Strongylus equinus (Chromadorea: Strongylidae): Comparison with other closely related species and phylogenetic analyses

The roundworms of genus Strongylus are the common parasitic nematodes in the large intestine of equine, causing significant economic losses to the livestock industries. In spite of its importance, the genetic data and epidemiology of this parasite are not entirely understood. In the present study, the complete S. equinus mitochondrial (mt) genome was determined. The length of S. equinus mt genome DNA sequence is 14,545 bp, containing 36 genes, of which 12 code for protein, 22 for transfer RNA, and two for ribosomal RNA, but lacks atp8 gene. All 36 genes are encoded in the same direction which is consistent with all other Chromadorea nematode mtDNAs published to date. Phylogenetic analysis based on concatenated amino acid sequence data of all 12 protein-coding genes showed that there were two large branches in the Strongyloidea nematodes, and S. equinus is genetically closer to S. vulgaris than to Cylicocyclus insignis in Strongylidae. This new mt genome provides a source of genetic markers for the molecular phylogeny and population genetics of equine strongyles.

Evaluation of the specificity of five oligoprobes for identification of cyathostomin species from horses

Here, we report evaluation of five oligoprobes designed from intergenic spacer (IGS) region sequences for identification of cyathostomin species. Oligoprobes were designed for identification of Cylicocyclus ashworthi, Cylicocyclus nassatus, Cylicostephanus longibursatus, Cylicostephanus goldi and a fifth probe designed to identify all members of this tribe. PCR amplification of IGS DNA from 16 cyathostomin species allowed sequence comparison and identification of four putative species-specific probes. Southern blotting of amplified products from 16 species showed that all probes were species-specific. The fifth probe recognised all 16 cyathostomin species but did not bind to members of the genus Strongylus. Furthermore, these probes were used to identify individual infective L3, eggs and L4 indicating that they will be invaluable to furthering the study of the epidemiology and pathogenesis of these important equine nematodes.

A new species of the genus Strongylus muller, 1780 from the black rhinoceros, Diceros bicornis L. and a note on the other species occuring in Kenya.

Strongylus (Dicerocola) tremletti sp.nov. is described from the black rhinoceros, Diceros bicornis L. from Kenya.The affinities of S. (D.) tremletti sp.nov. with the other species of the genus Strongylus Müller, 1780 are discussed and the subgenus Dicerocola subgen.nov. is erected to contain it.The species of Strongylus in Kenya are noted and original drawings of S. (D.) asini Boulenger, 1920 are included.

On the Morphology and Systematic Position of Echinopharynx, a New Genus of Bursate Nematode from Testudo tabulata

Our present knowledge of the Strongylid parasites of reptiles is based primarily on Dujardin (1845), who refers all the forms along with those of other vertebrates under a common genus Strongylus, and described four species from the reptilian hosts. Since then our knowledge of parasitic fauna has considerably increased, and von Linstow (1878–89) gave an enlarged list under the same genus from reptiles and also a few under the genus Kalicephalus, Later, with improved methods of Nematode study the forms described were revised, and it was found necessary to split the genus Strongylus, and several groups of a diverse character were recognised. The genus Strongylus was thus split up into several genera, and some of them were removed from the family Strongylidæ. The form Strongylus dispar of Dujardin from the Anguis fragilis was removed into a separate genus, Oswaldocruzia and Strongylus auricularis, with its characters in the absence of buccal capsule and the bifid and trifid distal ends of the spicule seemed more closely allied to Trichostrongylidæ Leiper, and was also removed to the genus Oswaldocruzia.

Observations on Hyostrongylus rubidus (Hassall and Stiles 1892) Hall 1921, from the Stomach of the Pig, with a note on Strongylus attenuatus (Molin 1860)

Hassall and Stiles (1892) described this delicate parasite and gave it the name Strongylus rubidus. Our knowledge of it has recently been increased by Hall (1921) who has shown that it is not a member of the genus Strongylus, as represented by S. equinus of the horse, but is a member of the family Trichostrongylidæ. He has created a new genus Hyostrongylus for its reception and has devoted a large part of his paper to the consideration of a male accessory organ which serves as a guide for the spicules and to which he gives the name telamon.

Note on the Genus Diaphanocephalus (Nematoda: Strongylidae), Parasitic in Reptiles, with a Description of Three New Species

The genus Diaphanocephalus was erected by Diesing in 1851 to contain certain species included in Rudolphi's Synopsis in the old genus Strongylus. The species in question were Strongylus galeatus Rud., 1819, re-named Diaphanocephalus strongyloides by Diesing, and subsequently indicated as the type-species of the genus; S. costatus; and possible S. viperae Rud., which Diesing listed as a species inquirenda. In deciding upon the necessity for the new genus Diesing seems to have been influenced largely by the characters of the head. His diagnosis shows that he considered the supporting rays of the buccal capsule to be four only in number, regarding two of these as divided each into two distinct processes. Molin (1861) gave an emended diagnosis of Diesing's genus and proposed the new genus Kalicephalus for certain other strongyle parasites in reptiles. It has already been pointed out (Baylis and Daubney) that the generic characters used by Molin are unreliable and that Railliet and Henry (1909) were justified in abolishing Kalicephalus in favour of the older genus, Diaphanocephalus. Recently, Skrjabin (1916) has given a diagnosis of the genus. Through the kindness of Dr H. A. Baylis the writer has been able to examine specimens in the collection of the British Museum (Natural History), and the Wellcome Bureau of Scientific Research. The material examined includes four specimens of the genus Diaphanocephalus.

On the Anatomy of four species of Entozoa belonging to the genus Strongylus, from the Delphinus phocœna, or common Porpoise

On the Anatomy of four species of Entozoa belonging to the genus Strongylus, from the Delphinus phocœna, or common Porpoise