Detection and genetic characterization of Giardia duodenalis in pigs from large-scale farms in Xinjiang, China

Abstract

To study the presence of Giardia duodenalis in Xinjiang, northwest China, we collected 801 fecal specimens from seven large-scale pig farms and screened them using PCR targeting the SSU rRNA gene. Twenty-one (2.6%) of the specimens from five farms were G. duodenalis-positive, with a significant difference in prevalence among different farms (0–8.7%) (p 0.05). Sequence analysis of the SSU rRNA gene revealed that the 21 G. duodenalis strains belonged to three assemblages: A (n = 2), B (n = 16), and E (n = 3). Assemblage B was the predominant assemblage and was widely distributed in all G. duodenalis-positive farms and age groups. All G. duodenalis-positive specimens were further assayed at the β-giardin (bg), glutamate dehydrogenase (gdh), and triosephosphate isomerase (tpi) genes, and two tpi, four gdh, and two bg sequences were identified. These data indicate that pigs may be a zoonotic risk and can potentially spread G. duodenalis infection from animals to humans.

Keywords

• Giardia duodenalis
• Prevalence
• PCR
• Assemblages
• Zoonoses