Evidence of red panda as an intermediate host of Toxoplasma gondii and Sarcocystis species

Abstract

Toxoplasma gondii has been found to infect almost all warm-blooded animals; however, some hosts lack direct evidence of T. gondii infection. The red panda ( Ailurus fulgens ) is an endangered species that mainly lives in temperate forests of South Asia. Here, T. gondii infection in red pandas from zoos in China were reported. Antibodies to T. gondii were found in 14.3% (2/14) of red pandas via the modified agglutination test (MAT) with a cut-off titer of 1:25. One viable T. gondii strain was isolated from tissues of red panda and designated as TgRedpandaCHn1. DNA from tachyzoites obtained from cell culture was characterized by PCR-RFLP with 10 markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29–2, L358, PK1, and Apico) and virulence genes of ROP5 and ROP18. The results indicate that this isolate belonged to ToxoDB genotype #20. The ROP18/ROP5 genotype combination predicated that this strain is non-lethal to mice, which is supported by the infection in mice. T. gondii tissue cysts were readily formed and mice survived. Tissue cysts observed in the histopathological sections of the tongue and diaphragm of one red panda were speculated as sarcocysts, but not T. gondii base on morphological characteristics. To our knowledge, this study is the first to report on the isolation of T. gondii from red panda. Additionally, this report provides direct evidence of red panda as an intermediate host of T. gondii and Sarcocystis species.

Additional evidence of tigers (Panthera tigris altaica) as intermediate hosts for Toxoplasma gondii through the isolation of viable strains

“…The genotype of TgTigerCHn4 was ToxoDB#2, and 3/3 for the ROP18/ROP5 combination, indicating avirulence for mice. The genotype of ToxoDB#20 has been reported in cats, dogs, sand cats, red pandas, and serval from Africa and Asia ( Dong et al, 2019 ; Dubey et al, 2007 , 2010 , 2013 ; El Behairy et al, 2013 ; Al-Kappany et al, 2010 ; Tian et al, 2014 ; Yang et al, 2019b ). ToxoDB#20 T. gondii strains have been found in red pandas and serval from central China, both were 3/4 for the ROP18/ROP5 combination, avirulence for mice and low rate of brain cyst formation ( Dong et al, 2019 ; Yang et al, 2019b ).…”

Isolation, genotyping and pathogenicity of a Toxoplasma gondii strain isolated from a Serval ( Leptailurus serval ) in China

“…Information regarding the geographic distribution of ToxoDB#20 is summarized in Figure . ToxoDB#20 isolates have been isolated from cats (Al‐Kappany et al, ; Dubey et al, ; Tian et al, ), dogs (Behairy et al, ; Dubey et al, ), sand cats (Dubey et al, ) and red pandas (Yang et al, ). Comparison of genotypes indicated that ToxoDB#20 differs from Chinese 1 (ToxoDB#9) at locus PK1, but they probably belong to the same ancestral clade with Type II lineage.…”

“…The virulent phenotype was supported by infection in mice (low cyst formation rate and avirulence) (Table ). The other ToxoDB#20 strain isolated from a red panda ( Ailurus fulgens ) was also avirulent in mice, and it also had the same ROP18 / ROP5 genotype as TgServalCHn1 (Yang et al, ).…”

Isolation and Genetic Characterization of Toxoplasma gondii from a Patas Monkey (Erythrocebus patas) in China

“…The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/genes14081606/s1, Table S1: Summary of viable T. gondii isolates (n = 169) from animals and humans in China [62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77].…”

“…The following supporting information can be downloaded at: , Table S1: Summary of viable T. gondii isolates (n = 169) from animals and humans in China [ 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 ].…”