Characterization of Baylisascaris schroederi from Qinling subspecies of giant panda in China by the first internal transcribed spacer (ITS-1) of nuclear ribosomal DNA

Abstract

In the present study, a total of 20 nematode isolates, (including 10 male and 10 female worms) representing Baylisascaris schroederi from 5 Qinling subspecies of giant pandas (Ailuropoda melanoleuca) in Shaanxi Province of China, were characterized and grouped genetically by the first internal transcribed spacer (ITS-1) of nuclear ribosomal DNA (rDNA). The rDNA fragment spanning 3' end of 18S rDNA, complete ITS-1 rDNA, and 5' end of 5.8S rDNA were amplified and sequenced. The sequence variability in ITS-1 rDNA was examined within B. schroederi and among parasites in order Ascaridata available in GenBank™, and their phylogenetic relationships were also reconstructed. The sequences of ITS-1 rDNA for all the B. schroederi isolates were 427 bp in length, with no genetic variation detected among these isolates. Phylogenetic analyses based on the ITS-1 rDNA sequences revealed that all the male and female B. schroederi isolates sequenced in the present study were posited into the clade of genus Baylisascaris, sistered to zoonotic nematodes in genus Ascaris, and the ITS-1 rDNA sequence could distinguish different species in order Ascaridata. These results showed that the ITS-1 rDNA provides a suitable molecular marker for the inter-species phylogenetic analysis and differential identification of nematodes in order Ascaridata.

Analysis of the genetic diversity of the nematode parasite Baylisascaris schroederi from wild giant pandas in different mountain ranges in China

“…Our assessment of population genetic structure using the Fst index revealed an absence of significant differentiation among the three B . schroederi populations (including Qinling mountain), consistent with previous reports based on the ribosome DNA (ITS-1, ITS-2 and 5.8S) [9,28]. Furthermore, the high Nm value indicated the occurrence of strong gene flow among the B .…”

Potential of recombinant inorganic pyrophosphatase antigen as a new vaccine candidate against Baylisascaris schroederi in mice

“…B. schroederi is increasingly recognized as an important cause of mortality in giant pandas [4,7,8,14], but a preventative vaccine is currently lacking. As PPases are essential for growth and viability in various organisms including parasites [21,22], they are attractive targets for vaccine development against parasitic infections.…”

“…This parasite (at the adult stage) usually inhabits the intestines of the giant panda, while its migrating larvae may disseminate into various body tissues. B. schroederi can induce extensive inflammation and scarring of the intestinal wall and parenchyma of the liver and lung (mainly caused by larvae), as well as intestinal obstruction, inflammation and even death (caused by adults) in giant pandas [9,12-14]. Until now the control of B. schroederi infection in pandas is relied chiefly on chemotherapy, and treatment with antiparasitic drugs requires multiple doses until the animal ceases to expel worms or shed eggs in feces [9].…”

Baylisascaris sp. infection in a pet kinkajou Potos flavus

“…in the specific zone of the ITS2 region (positions 246 and further). Nine G-A tandem repeats were identified for B. procyonis, eight for B. transfuga, seven and six for the two B. columnaris genotypes, and one for B. schroederi that likely represents the ancestral state of the given DNA region (Testini et al, 2011;Lin et al, 2012;Franssen et al, 2013). For the JP1 isolate, 11 tandem contiguous G-A repeats were recorded in the respective locations.…”