Development and Field Testing of a Real-Time PCR Assay for Caprine Arthritis-Encephalitis-Virus (CAEV)
Giovanni Brajon*, 1, Daniela Mandas 2, Manuele Liciardi 4, Flavia Taccori 1, Mauro Meloni 2, Franco Corrias 1, Caterina Montaldo 5, Ferdinando Coghe 2, Cristina Casciari 3, Monica Giammarioli 3, Germano Orrù*, 2, 5
Identifiers and Pagination:Year: 2011
First Page: 82
Last Page: 90
Publisher Id: TOVJ-6-82
Article History:Received Date: 17/2/2012
Revision Received Date: 10/5/2012
Acceptance Date: 14/5/2012
Electronic publication date: 27/7/2011
Collection year: 2012
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http: //creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Caprine arthritis/encephalitis (CAE) of goats and occasionally sheep are persistent virus infections caused by a lentivirus (CAEV). This viral infection results in arthritis in adult animals and encephalitis in kids. Prognosis for the encephalitic form is normally poor, with substantial economic loss for the farm. In this context an early/fast laboratory diagnosis for CAEV infection could be useful for effective prophylactic action. In this work we performed a quantitative real time PCR designed on the CAEV env gene to detect/quantify in goat/sheep samples, viral RNA or proviral DNA forms of CAEV. This procedure was validated in 15 sheep, experimentally infected with CAEV or with a highly correlated lentivirus (visna maedi, MVV); in addition, a total of 37 clinical goat specimens recruited in CAEV positive herds were analyzed and compared using serological analysis (Elisa and AGID). All samples infected with MVV resulted negative. In sheep experimentally infected with CAEV, proviral DNA was detectable 15 days post infection, whereas the serological methods revealed an indicative positivity after 40-60 days.This method showed a sensitivity of 102 env fragments/PCR) with a linear dynamic range of quantitation from 103 to 107env fragments/PCR; the R2 correlation coefficient was 0.98. All subjects with a clinical diagnosis for Caprine Arthritis-Encephalitis (CAE) resulted CAEV DNA positive.