Isolation and Pathogenic Characterization of Pigeon Paramyxovirus Type 1 via Different Inoculation Routes in Pigeons

Abstract

Pigeon paramyxovirus type I (PPMV-1) causes regular outbreaks in pigeons and even poses a pandemic threat among chickens and other birds. The birds infected with PPMV-1 mainly show a pathological damage in the respiratory system, digestive system, and nervous system. However, there were few reports on the efficiency of the virus entering the host via routes of different systems. In the present study, a PPMV-1 strain was obtained from a dead wild pigeon in 2016 in Beijing, China. The mean death time (MDT) and the intracerebral pathogenicity (ICPI) of our isolate showed medium virulence. Phylogenetic analysis based on F gene sequence showed that the isolate belonged to subgenotype VIb, class II, which dominated in China in recent years. Then, we evaluated the infection efficiency of different routes. Pigeons were randomly divided into five groups of six as follows: intracephalic (IC), intranasal (IN), and intraoral (IO) infection routes, cohabitation infection (CO), and negative control (N negative). All pigeons were inoculated with 100 μl·106 EID50 PPMV-1 virus. After infection, pathological lesions, virus shedding, body weight change, survival rate, and tissue tropism were tested to compare the efficiency of the different infected routes. The mortality of groups IC, IN, IO, and CO were 100, 66.7, 50, and 33.3%, respectively. Weight loss in group IC was higher than the other groups, followed by groups IN and IO. The lesions observed in PPMV-1-infected pigeons were severe, especially in the lung and intestine in group IC. Viral shedding was observed from 2 dpi in groups IC and IN, but the shedding rate was higher in group IN than group IC. The longest period was in group CO. Tissue tropism experiment showed that our isolate has a wide range of tissue distribution, and the virus titer in the heart and intestine of group IC and in the brain of group IN was higher. Our data may help us to evaluate the risk of transmission of PPMV-1.

Detection of Avian Orthoavulavirus-1 genotypes VI.2.1 and VII.1.1 with neuro-viscerotropic tropism in some backyard pigeons (Columbidae) in Eastern Saudi Arabia

“…Natural infection of pigeons and doves with viruses of genotype VI.2.1 (nucleotide identity of >95%) was reported to induce Additionally, comparable nervous signs and mortality rates were observed on birds from which similar VI.2.1 sequences (> 95%) were recovered (56, 63, 64). Likewise, similar nervous signs were reported in pigeons infected with less similar isolates of genotype VI.2.1 (54,65) (61,70). RT-PCR, followed by sequencing of the F gene, has been widely used to detect virulence and to connect AOAVs recovered from different outbreaks (65).…”

“…Nevertheless, signs of respiratory involvement in pigeons were observed following a natural infection with genotype VI.1.1 ( 69 ). Additionally, efficient viral replication in the brain, trachea, and intestine of pigeons experimentally infected with strains of genotypes VI.2.2.2.1 and VI.1.1 was reported ( 61 , 70 ).…”

Isolation, full sequence analysis, and in situ hybridization of pigeon paramyxovirus-1 genotype VI.2.1.1.2.2 from oriental turtle doves (Streptopelia orientalis)

“…The affected pigeons and doves show nonspecific clinical signs, such as depression, lethargy, wet dropping, neurological signs, and gross lesions, including an enlarged pale spleen and pancreas, and pale kidneys with white pinpoint foci. Microscopically, lymphoplasmacytic infiltration in multiple organs such as the heart, liver, pancreas, kidney, gizzard, and cerebrum are usually observed ( Isidoro-Ayza et al, 2017 ; Chang et al, 2021 ; Rogers et al, 2021 ). Notably, PPMV-1 not only causes lesions in experimentally inoculated chickens ( Kommers et al, 2002 ), but also leads to outbreaks in poultry farms in Europe and South Africa, thus resulting in economic losses due to the disease, stamping out, and trading embargoes ( Alexander et al, 1997 ; Abolnik et al, 2004 ; Irvine et al, 2009 ).…”