Isolation and characterization of a subtype C avian metapneumovirus circulating in Muscovy ducks in China

Abstract

Subtype C avian metapneumovirus (aMPV-C), is an important pathogen that can cause egg-drop and acute respiratory diseases in poultry. To date, aMPV-C infection has not been documented in Muscovy ducks in China. Here, we isolated and characterized an aMPV-C, designated S-01, which has caused severe respiratory disease and noticeable egg drop in Muscovy duck flocks in south China since 2010. Electron microscopy showed that the isolate was an enveloped virus exhibiting multiple morphologies with a diameter of 20-500 nm. The S-01 strain was able to produce a typical cytopathic effect (CPE) on Vero cells and cause death in 10-to 11-day-old Muscovy duck embryos. In vivo infection of layer Muscovy ducks with the isolate resulted in typical clinical signs and pathological lesions similar to those seen in the original infected cases. We report the first complete genomic sequence of aMPV-C from Muscovy ducks. A phylogenetic analysis strongly suggested that the S-01 virus belongs to the aMPV-C family, sharing 92.3%-94.3% of nucleotide identity with that of aMPV-C, and was most closely related to the aMPV-C strains isolated from Muscovy ducks in France. The deduced eight main proteins (N, P, M, F, M2, SH, G and L) of the novel isolate shared higher identity with hMPV than with other aMPV (subtypes A, B and D). S-01 could bind a monoclonal antibody against the F protein of hMPV. Together, our results indicate that subtype-C aMPV has been circulating in Muscovy duck flocks in South China, and it is urgent for companies to develop new vaccines to control the spread of the virus in China.

Avian Viruses that Impact Table Egg Production

“…The pathogenicity of AMPV for the chicken’s oviduct was shown to be higher in the uterus than in the magnum and isthmus, which suggests a different susceptibility of epithelial cells for the three parts of the chicken’s oviduct [ 62 ]. In China, a similar disease picture was reported in egg-laying Muscovy ducks [ 63 ]. In Italy, longitudinal studies and sporadic samplings indicated that most pullet flocks get infected with AMPV before the laying begins [ 64 ].…”

Isolation and Characterization of a Novel Tembusu Virus Circulating in Muscovy Ducks in South China

“…Since 2011, Muscovy ducks have been affected by a severe disease with egg‐drop and ovary–oviduct symptoms, which has been spreading through farms in South China. At first, the causative agent of this disease was suspected to be subtype C avian metapneumovirus (Sun et al., ). However, despite the implementation of a vaccine against this pathogen, the disease continued to spread.…”