Intestinal growth and pathology of Giardia duodenalis assemblage subtype A(I), A(II), B and E in the gerbil model.

This study investigated the significance of the genetic differences between assemblages A, B and E on intestinal growth and virulence. Intestinal growth and virulence were studied in 2 laboratory (A(I): WB and B: GS/M-83-H7) and 6 field isolates of assemblage subtype A(I), A(II), B and E(III). Intestinal trophozoite burdens, body weight and faecal consistency were monitored until day 29 post-infection (p.

Giardia duodenalis cyst survival in cattle slurry.

Giardia duodenalis is a protozoan parasite known to infect animals and humans. Zoonotic transmission of G. duodenalis can occur by the consumption of drinking water produced from surface water that is contaminated by runoff from manure-laden fields or pastures.

Intrinsic susceptibility of Giardia duodenalis assemblage subtypes A(I), A(II), B and E(III) for nitric oxide under axenic culture conditions.

The antigiardial effects of nitric oxide (NO·) have been reported in vitro, but only for assemblage A(I) lab strains. This study investigated the intrinsic NO· susceptibility of different assemblage subtypes. The susceptibility (IC₅₀) for NO· released by MAHMA NONOate was studied for three lab (WB, G1 and GS/M-83-H7) and six field isolates of assemblage subtypes A(I), A(II), B and E(III).

Variation in growth and drug susceptibility among Giardia duodenalis assemblages A, B and E in axenic in vitro culture and in the gerbil model.

This study investigated the molecular and biological variation among different Giardia duodenalis assemblages. In vitro growth and susceptibility to albendazole, fenbendazole, flubendazole, metronidazole, tinidazole and furazolidone was studied for laboratory (AI: WB, AII: G1 and B: GS/M-83-H7) and 6 field isolates of assemblage subtype AI, AII, B and EIII. Additionally, isolates of the 3 assemblages were evaluated in the gerbil upon 3-day oral treatment with albendazole (6 mg/kg), flubendazole (5 mg/kg) and metronidazole (20 mg/kg).

Infectivity of Giardia duodenalis Assemblages A and E for the gerbil and axenisation of duodenal trophozoites.

Establishing in vitro cultures of Giardia duodenalis trophozoites from faecal cysts remains very difficult due to poor excystation and bacterial contamination. This study investigated an alternative approach starting from duodenal trophozoites of gerbils that were artificially infected with field isolates from humans (Assemblages A and B) and cattle (Assemblage E and mixed E/A). Gerbil infection was successful for Assemblages A (1/1) and B (1/3) from humans, and for E (1/2) and mixed E/A (6/6) from cattle.