Rhipicephalus sanguineus (Ixodida, Ixodidae) as intermediate host of a canine neglected filarial species with dermal microfilariae

The life cycles of filarioids of dogs presenting dermal microfilariae have been little studied. Following the recent retrieval of dermal microfilariae identified as Cercopithifilaria sp. in a dog from Sicily (Italy), this study was designed to assess the role of the brown dog tick Rhipicephalus sanguineus as an intermediate host of this filarial species. An experimental tick infestation was performed on an infected dog using 300 nymphs of R. sanguineus. Engorged nymphs were collected and examined by both microscopic dissection and molecular analysis at five time points (i.e., the same day of tick detachment and 10, 20, 30 and 50 days post-detachment) to detect the presence and developmental stage of filariae in the ticks. A total of 270 engorged nymphs were collected from the dog and developing filarioid larvae detected in 10 (5%) out of 200 ticks dissected. Infective third-stage larvae were observed in 4 (2%) of the all dissected ticks, 30 days post-detachment. Twelve (6.6%) out of 181 samples molecularly tested were positive for Cercopithifilaria sp. This study demonstrates that nymphs of R. sanguineus feeding on a dog naturally infected by Cercopithifilaria sp. can ingest microfilariae, which develop up to the third infective stage thus suggesting that this tick species might act as an intermediate host of this little known canine filarioid.     

Morphological and molecular data on the dermal microfilariae of a species of Cercopithifilaria from a dog in Sicily

Dermal microfilariae found in a dog from Sicily, Italy, were characterized morphologically and genetically and differentiated from those of all the other blood microfilariae commonly found in dogs. In particular, the microfilariae were short (mean length of 186.7 μm), presented a body flattened dorso-ventrally and a rounded head, bearing a tiny cephalic hook. The genetic identity of microfilariae herein studied was also assessed by molecular amplification, sequencing and analyzing of multiple ribosomal ITS-2 and mitochondrial (cox1 and 12S) target genes. Both morphologic and genetic characterization as well as the molecular phylogenetic history inferred using sequences of a barcoding dataset were concordant in supporting the identification of Cercopithifilaria at the genus level. Surprisingly, microfilariae here examined were well distinct from Cercopithifilaria grassii (Noè, 1907), from northern Italy, and resembled those of a species described in Brazil, Cercopithifilaria bainae Almeida & Vicente, 1984. This paper provides evidence for the existence of a Cercopithifilaria species infesting a dog from Sicily and also presents a PCR protocol on skin samples as a tool for further epidemiological studies, which could provide evidence on the aetiology and the natural history of this filarial species.     

Pathological changes caused by Anoplocephala perfoliata in the mucosa/submucosa and in the enteric nervous system of equine ileocecal junction

In this study, pathological changes caused by Anoplocephala perfoliata in the ileocecal junction were investigated in 31 regularly slaughtered mixed-breed horses of both sexes. Our results showed a significant relationship between parasite burden and grading of histopathological lesions in the mucosa and submucosa. Hypertrophy of the circular muscle layer was found in infected horses. Moreover, enteric nervous system evaluation showed a significant injury of intestinal nervous elements in the horses with moderate to high parasitism expressed as an increase of degenerative-regressive changes in neuronal cells and a decrease in the number of myenteric ganglia and neuronal cells. These findings can help to clarify the pathogenesis of intestinal motility disorders associated with A. perfoliata infection in horses.     

Efficacy of eprinomectin pour-on against Dictyocaulus arnfieldi infection in donkeys (Equus asinus)

A trial to assess the efficacy of eprinomectin (EPM) against the lungworm Dictyocaulus arnfieldi was carried out on 15, naturally-infected donkeys. Ten animals were treated with a ‘pour-on’ EPM preparation (at a dose of 0.5 mg/kg bodyweight), and five animals acted as controls. Faecal larval counts were carried out two days before treatment, on day of treatment and 7, 14, 21 and 28 days post-treatment with the anthelmintic. EPM was 100% effective in eliminating faecal larvae from day 7, until the end of study at day 28. No adverse drug-reactions or side-effects were observed in any of the treated donkeys.     

Use of a Health Information System (HIS) for the Epidemiological Surveillance of Leishmaniasis in Urban Areas

Veterinary Research Communications - Brianti, E., Drigo, M., Zirilli, V., Poglayen, G. and Giannetto, S., 2007. Use of a Health Information System (HIS) for the epidemiological surveillance of...     

Simultaneous detection of the feline lungworms Troglostrongylus brevior and Aelurostrongylus abstrusus by a newly developed duplex-PCR

In addition to Aelurostrongylus abstrusus (Strongylida: Angiostrongylidae), referred to as the feline lungworm, Troglostrongylus brevior (Strongylida: Crenosomatidae) has recently been identified as an agent of bronco-pulmonary infestations in cats. These two parasites have a similar biology, share ecological niches, potentially co-infesting cats, but are difficult to be differentiated due to the morphological similarities of their first-stage larvae (L1). This paper describes a molecular tool, based on single-step duplex polymerase chain reaction (duplex-PCR) on the ribosomal internal transcribed spacer 2 region (ITS-2) for the simultaneous detection and differentiation of T. brevior and A. abstrusus. L1 of both species were collected from faecal samples, morphologically identified, and single larval specimens isolated. An aliquot of faeces was used as a test sample for a case of mixed natural infestation. The duplex-PCR was performed using species-specific forward primer sets for the ITS-2 region (i.e., A. abstrusus: 220 bp; T. brevior: 370 bp). The detection limit of the molecular assay was also assessed by serial dilutions of DNA from single larvae of both species (from ～4.0 to 4.0 × 10^?5 μg/μl). The duplex-PCR carried out on individual DNA samples was able to detect as low as 5.2 × 10^?3 μg/μl of DNA for A. abstrusus, 4.9 × 10^?3 μg/μl for T. brevior, and as low as 4.0 × 10^?3 μg/μl for samples containing both species. Species-specific bands of the expected sizes and two bands were simultaneously amplified from the faecal sample containing both species. The phylogenetic analyses of the ITS-2 sequences here examined and those available for other metastrongyloids were concordant in clustering them with those of other Troglostrongylus brevior and A. abstrusus sequences available in GenBank database. This molecular approach proved to be effective and highly sensitive for the simultaneous detection of the two lungworms species and it might be used for molecular epidemiological studies and for monitoring therapeutic protocols.