Search

Porcine parvovirus (PPV) is an important pathogen causing reproductive disorders in sows, with clinical symptoms including stillbirth, mummified fetuses, embryonic dysplasia and death, and sow infertility. Porcine parvovirus 7 (PPV7) is a recently discovered type of PPV and its widespread distribution and rapid evolution has caused huge economic losses in the pig industry. To investigate the molecular epidemiology of PPV7 in Fujian Province, China, we collected 491 blood samples and 72 tissue samples from diseased pigs in large-scale pig farms across selected areas of Fujian Province from 2019 to 2022. PPV7 infection was determined using real-time quantitative PCR, and positive samples underwent whole-genome amplification, sequencing, and subsequent homology, phylogenetic, and recombination analyses. The PPV7 positive detection rate was 25.73% (145/563) in Fujian Province, among which the positive rate of blood and tissue samples was 26.47% (130/491) and 20.83% (15/72), respectively. The nucleotide sequence homology among the 29 PPV7 whole-genome sequences obtained in this study was 90.0%–97.2%, whereas that with 128 reference strains from China and other countries was 88.9%–98.1%. Six strains had partial nucleotide deletions or insertions. Phylogenetic analysis based on the whole-genome sequences classified the 29 PPV7 strains and 128 reference strains into eight subtypes (PPV7a–PPV7h), and PPV7h was the predominant subtype in Fujian Province. Recombination analysis revealed evidence of inferred recombination events in the genomes of four strains. This study provides significant insights into the molecular characteristics of PPV7 in Fujian Province and serves as a crucial foundation for further advancements in PPV7 prevention and control strategies. • Whole-genome sequences of 29 strains of porcine parvovirus 7 (PPV7) were analyzed. • Phylogenetically, the 29 PPV7 strains in Fujian Province were categorized into 8 subtypes. • Six strains of PPV7 had partial nucleotide deletions or insertions. • Genetic evolutionary analysis reflected that PPV7 h is the main prevalent strain in Fujian Province. [ABSTRACT FROM AUTHOR]

A prevalent PEDV strain, designated FJLY06, was isolated from Fujian, China. The four of structural genes sequences of PEDV obtained were analyzed to determine their phylogenetic relationships and homology respectively, revealing that FJLY06 was highly homologous to virulent PEDV strains. The four structural genes all differed genetically from the vaccine strain CV777. The sequence alignment results further showed that N, M and E genes of Chinese PEDV strains is highly conserved. Compared with the vaccine strain CV777, 8 mutations were detected in COE of FJLY06 S gene. The recombination analysis revealed FJLY06 is similar to other pandemic strains in China with a variant S gene, and maybe a reason for recent vaccination failures. [ABSTRACT FROM AUTHOR]