Comparative study of effects of assemblages AII and BIV of Giardia duodenalis on mucosa and microbiota of the small intestine in mice

Abstract Aims Giardiasis is one of the major causes of diarrhea worldwide and its symptoms vary in intensity, which can be attributed to different parasite assemblages. The goal of the present study was to compare the effects of infection caused by assemblages AII and BIV of Giardia duodenalis on the response of the small intestine, microbiota, and behavioral parameters in mice. Main methods Swiss mice were infected with assemblages AII and BIV of G. duodenalis for 15 days. Leucometry, pain, intestinal microbiota and histological parameters of the duodenum and jejunum were evaluated in the experimental groups. Key findings Both assemblages modified the composition of the intestinal microbiota. Infection with assemblage AII promoted leukocytosis, reflected by increasing number of polymorphonuclear cells, intraepithelial lymphocytes and pain-related behavior, indicating that this was the more aggressive assemblage with regard to its effects on the intestinal mucosa and duodenum. Significance The specific assemblage of the parasite is an important parameter that affects symptomatology in the host.