Abstract
In endemic places, liver hydatidosis is a life-threatening health issue. Many consequences such as hepatomegaly, infiltration with inflammatory cells and histopathological changes might arise as a result of liver hydatidosis. This study aimed to look into pathogenic changes in the livers of the rats that experimentally infected with hydatid cysts. These hydatid cysts were isolated from naturally infected humans, sheep, goats and cows. Liver hydatid cysts were collected from the main abattoir of Al-Muthanna province while human hydatid cysts were collected from Al-Hussein Teaching Hospital in Al-Muthanna province. The hydatid cysts were grossly and histology examined for inspection of hydatid cysts. The in vivo experiments were done by injection of hydatid protoscoleces or sand (fluid) in rats intraperitoneally. The results showed that the gross signs were same in all infected livers which range from paleness, hepatomegaly, hemorrhage and calcification. The hydatid cysts isolated from sheep and goat livers were highly fertile compared to others isolated from humans and cows. Injection of hydatid protoscoleces and hydatid fluid isolated from sheep and goat livers in rats induced the highest immune response compared to that isolated from humans and cows. The liver sections of rats that were injected with human, goat and sheep hydatid protoscoleces and fluids showed hyperplasia in the bile duct, aggregation nonnuclear cells with congested blood vessels. While liver sections of rats were received goat hydatid fluid, cow hydatid protoscoleces and hydatid fluid showed normal liver tissue. These findings suggested that the immunogenicity of hydatid materials is different according to the host and the component of hydatid cysts.