Identification of a Feline Panleukopenia Virus from Captive Giant Pandas (Ailuropoda melanoleuca) and Its Phylogenetic Analysis

Abstract

The host range of feline panleukopenia virus (FPV) is expanding and is a serious threat to both captive and free-range endangered wildlife. The FPV named FPV-am2020 was isolated from fecal samples from four diarrheal captive giant pandas in 2020, and pathogenicity and phylogenetic analysis were conducted in this study. Three-month-old cats challenged with FPV-am2020 experienced 100% mortality. The complete FPV-am2020 sequence was determined and comprised 5277 base pairs (bp), 36.76% GC content, and two open reading frames. According to the phylogenetic analysis of whole genome sequences and VP2 gene sequences, FPV-am2020 was closely related with MG764511.1 (isolated from captive lions in China, 2015), KX685354.1 (isolated from captive tigers in China, 2016), and KX900570.1 (isolated from captive jaguar in China, 1986). Furthermore, the study identified a G299E mutation in VP2 which was a key residue involved in phenotype changes in FPV. Thus, increased surveillance of FPV mutant isolates must be enacted to protect giant pandas against potential viral threats.