A molecular survey on Avian Metapneumovirus (aMPV) diffusion was performed from 2011 to 2013 in 122 turkey and 48 broiler farms, located in a densely populated poultry area of Northern Italy. Turkeys were all vaccinated at 1 day of age in the hatchery. aMPV was detected using RTnested PCR or qRT-PCR; both tests are able to detect and differentiate aMPV subtypes A and B. All samples but one resulted positive for aMPV subtype B confirming the high prevalence of this subtype in Italy. The majority of aMPV detections were of field origin, circulating mainly in 9 to 12- week-old turkeys and 5 to 7 week-old broilers, showing respiratory signs. The reasons for vaccine failure could be due to field virus changes occurred in key antigenic regions, which allow virus replication and disease in well-vaccinated birds. Strains of vaccine origin were detected in turkeys with a high prevalence during the first few weeks after vaccination with aMPV live vaccines. This confirmed the pattern previously seen where vaccine viruses were shown to persist on farm for 4-5 weeks. Uniquely in this study, vaccine derived strains were detected in older turkeys of up to 84 days of age. Moreover, sequence analysis of F and G protein genes of selected strains was performed.
Titolo: | AN UPDATE ON THE EPIDEMIOLOGY OF AVIAN METAPNEUMOVIRUS IN ITALY | |
Autore/i: | M. Cecchinato; M. Drigo; LUPINI, CATERINA; M. Martini; LISTORTI, VALERIA; G. Franzo; LACONI, ANDREA; E. Morandini; C. J. Naylor; CATELLI, ELENA | |
Autore/i Unibo: | ||
Anno: | 2014 | |
Titolo del libro: | 8th SYPMOSIUM on ACOV & AMPV / 2nd MEETING COST ACTION 1207, RAUISCHHOLZHAUSEN, GERMANY, JUNE 2014 | |
Pagina iniziale: | 359 | |
Pagina finale: | 366 | |
Abstract: | A molecular survey on Avian Metapneumovirus (aMPV) diffusion was performed from 2011 to 2013 in 122 turkey and 48 broiler farms, located in a densely populated poultry area of Northern Italy. Turkeys were all vaccinated at 1 day of age in the hatchery. aMPV was detected using RTnested PCR or qRT-PCR; both tests are able to detect and differentiate aMPV subtypes A and B. All samples but one resulted positive for aMPV subtype B confirming the high prevalence of this subtype in Italy. The majority of aMPV detections were of field origin, circulating mainly in 9 to 12- week-old turkeys and 5 to 7 week-old broilers, showing respiratory signs. The reasons for vaccine failure could be due to field virus changes occurred in key antigenic regions, which allow virus replication and disease in well-vaccinated birds. Strains of vaccine origin were detected in turkeys with a high prevalence during the first few weeks after vaccination with aMPV live vaccines. This confirmed the pattern previously seen where vaccine viruses were shown to persist on farm for 4-5 weeks. Uniquely in this study, vaccine derived strains were detected in older turkeys of up to 84 days of age. Moreover, sequence analysis of F and G protein genes of selected strains was performed. | |
Data stato definitivo: | 11-giu-2017 | |
Appare nelle tipologie: | 4.01 Contributo in Atti di convegno |