HISTOPATHOLOGICAL EFFECT OF Giardia duodenalis ON LIVER AND INTESTINAL TISSUES IN A BALB/C MOUSE MODEL

Abstract

In this study, we build upon previous research by investigating the histopathological effects of *Giardia duodenalis* isolated from humans and dogs using a mouse model. A total of 20 BALB/c mice (average age: 8 weeks ± 2.4 days; average weight: 19.8 ± 0.5 g) were randomly divided into two groups of ten mice each. The unchallenged control group received no challenges and was orally administered 0.3 mL of normal saline. In contrast, the group challenged with Giardia duodenalis received a solution containing *G. duodenalis* at a concentration of 2 × 10⁴ cysts/mL in 0.3 mL, also orally. Clinical signs were monitored for 10 days, and body weights were recorded on days 0, 5, and 10. On day 10, tissue samples from liver and duodenum were collected and fixed in 10% formalin for histopathological analysis. Results showed that G. duodenalis-challenge significantly reduced the average body weights of mice on days 5 and 10 post-challenge. Histopathological results revealed that G. duodenalis-challenge caused hepatic blood vessel congestion, disappearance of hepatic cords, and pyknosis of hepatocytic nuclei. The intestinal histology was remarkably impacted with hyperplasia of goblet cells, cellular infiltration in the lamina propria, and extensive enterocyte damage. Additionally, numerous giardial parasites were observed in the mucus between the intestinal villi and lamina propria. These findings suggest that Giardia duodenalis isolates induce significant histopathological changes, primarily in the liver and intestines.