• Aucun résultat trouvé

A new high-throughput analysis to screen Ehrlichia ruminantium in field ticks

N/A
N/A
Info
Télécharger
Protected

Academic year: 2021

Partager "A new high-throughput analysis to screen Ehrlichia ruminantium in field ticks"

Copied!
2
0
0

Chargement.... (Voir le texte intégral maintenant)

Texte intégral

(1)

A new high-throughput analysis to screen Ehrlichia ruminantium in field ticks

Nathalie Vachiery1, Nidia Cangi1,2,3, Valerie Pinarello1, Laure Bournez1, Thierry Lefrançois3, Emmanuel Albina1, Luis Neves4

1: CIRAD, UMR CMAEE, F-97170 Petit-Bourg, Guadeloupe, France

2: Centro de Biotecnologia-UEM, Universidade Eduardo Mondlane, Maputo, Mozambiqueb 3: Université des Antilles, F-97110 Pointe à Pitre, Guadeloupe, France c

3: INRA, UMR CMAEE, F-34398 Montpellier, France

4: Department of Veterinary Tropical Diseases, University of Pretoria, Faculty of Veterinary Science, Onderstepoort, South Africa e.

In order to improve sample screening capacity of Ehrlichia ruminantium in ticks, an automatic DNA extraction method for Amblyomma ticks and a new QPCR targeting E. ruminantium pCS20 region, pCS20 Sol1 QPCR, were developed. A comparison between the new pCS20 Sol1 QPCR, a previously published pCS20 CowTM QPCR and the gold standard nested pCS20 PCR have been carried out. pCS20 Sol1TM QPCR was highly sensitive (up to 2.4 copies per sample) and specific (16 E. ruminantium strains detected and no cross-reaction with close-related species). We showed that Sol1 QPCR and pCS20 nested PCR had similar sensitivity and specificity however there was limited risk of contamination and timeless process for pCS20 Sol1 QPCR. In parallel, a tick 16SSyb rRNA QPCR was successfully developed for DNA quality control. DNA yield and quality from ticks extracted automatically, using 16SSyb rRNA QPCR were high. 16SSyb rRNA QPCR results (n=671 ticks) showed also a good reproducibility of automatic DNA extraction with a mean Ct=23+/-3. The whole method of screening, including automatic DNA extraction and pCS20 Sol1 QPCR, demonstrated a limit of detection between 6 and 0.6 copies per sample. It was also reproducible with restricted standard deviation of Ct (+/-1.3) for samples at the limit of detection. The development of a new automatic DNA extraction and QPCR allows for improving tick sample processing and E. ruminantium diagnostic capacities using high throughput methods. More widely, the automatic DNA extraction based on DNA/RNA virus kit

(2)

and the new DNA quality control method, 16SSyb rRNA QPCR, can then be used for screening other bacterium and virus and for other tick species.

Références

Télécharger maintenant ( PDF - 2 Page - 10.34 KB )

Documents relatifs

Phytoseiid mites of Rodrigues Island (Acari: Mesostigmata)

Phytoseiidae of La Réunion Island (Acari: Mesostigmata): three new species and two males described, new synonymies, and new records. First records of Phytoseiidae from one island of

Antimicrobial resistance in livestock sector in South Africa: lessons learnt from the past towards informed and prudent use of antibiotics, the example of poultry and milk sector

1 Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa.. 2 CIRAD, UMR Animal,

Genetic diversity of Ehrlichia ruminantium in Mozambique

variegatum and to determine the genetic diversity and structure of isolates from different localities, adult ticks feeding on cattle and wild ruminants were sampled across the

Efficient high-throughput molecular method to detect Ehrlichia ruminantium in ticks

Compared to the reference method (pCS20 nested PCR and combined with MLST), the relative sensitivity and specificity of the pCS20 Sol1 TqM qPCR was 75.8 and 85.2%, respectively with

Ehrlichia ruminantium detection using efficient high-throughput molecular method. [0088]

ruminantium molecular diagnostics, an automated DNA extraction method for Amblyomma ticks and a new qPCR targeting the pCS20 gene region were successfully developed. A comparison

Ehrlichia ruminantium prevalence in ticks and its genetic diversity in Mozambique. [0113]

ruminantium isolate structure in Mozambique, cattle and wildlife were sampled across the south and center of Mozambique as well as in the adjacent Kruger National Park (KNP),

Prevalence of bovine tuberculosis in cattle at the wildlife/livestock/human interface in Northern Kwazulu-Natal province, South Africa

Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, South Africa. Department of Production Animal Studies, Faculty of

Proceedings of the 2nd FARAH-Day / Faculty of Veterinary Medicine (University of Liege - Belgium)

Equine Clinic, Clinical Department of Companion Animals and Equids, Faculty of Veterinary Med-. icine,