Isolation and characterization of bovine parainfluenza virus type 3 from water buffaloes (Bubalus bubalis) in Argentina

Abstract

Background: Parainfluenza virus type 3 (PIV3) was isolated from dairy buffaloes (Bubalus bubalis) naturally affected with respiratory and reproductive clinical conditions.

Results: Examination of nasal and vaginal swabs collected from 12 diseased buffaloes led to the isolation of three paramyxovirus isolates from two animals. Antigenic, morphological and biological characteristics of these three isolates were essentially similar to those of members of the Paramyxoviridae family. Antigenic analysis by direct immunofluorescence and cross neutralization test placed these isolates together with bovine parainfluenza virus type 3 (BPIV3). Nucleotide and amino acid phylogenetic analysis of partial matrix gene sequences of the buffalo isolates and six field BPIV3 isolates from bovines in Argentina were studied. Buffalo isolates were similar to genotype B (BPIV3b) while the six BPIV3 isolates were similar to genotypes A (BPIV3a) and C (BPIV3c).

Conclusions: This is the first characterization of BPIV3 in water buffalo.According to the samples analyzed, in Argentina, the genotype B was found in buffalo and the genotypes A and C were found in cattle.

Figure 1

Microscopic examination of PIV3 isolated from buffaloes. A: Positive MDBK cells by IF, as observed by epifluorescence in an Olympus BX 40 + H hal microscope (400X magnification). B: Electron micrograph of two purified virions of the 7 N isolate, morphologically indistinguishable from paramixoviruses.

Figure 2

Nucleotide alignment of M fragment sequences of Argentine buffalo and bovine isolates, other bovine parainfluenza virus 3 and human parainfluenza virus 3 that circulate in the world. Dots indicate identity with respect to SF strain (AF178655).

Figure 3

Phylogenetic analysis based on M gene fragment. Phylogenetic analysis was performed using MEGA 4 software with 1,000 bootstrap replicates. Phylogenetic analysis based on M gene fragment nucleotide sequences compared to other Respirovirus genus members. The Argentinean isolates are indicated in bold. GenBank accession numbers are presented in Materials and Methods.