Changes

==Diagnosis==

==Diagnosis==

===Clinical Sgns===

===Clinical Signs===

Clinical signs are more likely to be seen in younger animals; older hosts are usually infected asymptomatically. Signs can be acute, transient, intermittent or chronic, can chronic infection can lead to debilitation. Malabsorbtion syndrome with soft, frothy, greasy, voluminous, malodourous faeces can occur.

Clinical signs are most likely to be seen in younger animals as older hosts are usually infected asymptomatically. Signs vary from acute diarrhoea to chronic loose, fould-smelling faeces, and frequency of defaecation is usually increased. Vomiting and weight loss may be seen in some cases. Malabsorbtion syndrome with soft, frothy, greasy, voluminous, malodourous faeces can occur.

Affected animals may show no clinical signs or, alternatively, may suffer from actue diarrhoea or chronic loose, foul smelling faeces typical of steatorrhea. Frequency of defaecation is normally increased. The clinical signs of giardiasis normally include diarrhoea, but vomiting and possibly weight loss, together with the presence of foul smelling faeces may be seen in some cases.

Giardiasis may also cause malabsorption, and there are several proposed mechanisms for this. For example, the small intestinal villi may be grossly atrophies or damages ultrastructurally, or giardiasis may lead to bacterial overgrowth. There is also evidence that ''[[Giardia]]'' consumes bile acids, preventing digestion of fats.

===Laboratory Tests===

===Laboratory Tests===