Question of the Day

Acute Haemonchus contortus infections in sheep are characterized by anemia and edema (such as the submandibular edema seen here). Chronic infections have similar clinical signs along with weight loss. Death can occur rapidly with hyperacute infections.

H. contortus are found in the abomasum. Click here to see a close-up of the “barber pole” appearance of H. contortus.

Heavy tapeworm infections can result in GI disturbances and unthriftiness but generally tapeworm infections are relatively nonpathogenic.

Chronic copper toxicosis in sheep manifests as a hemolytic crisis when the liver releases massive stores of copper (after long-term increased dietary copper) in response to stress.

Scrapie is a transmissible spongiform encephalopathy that affects sheep worldwide. It causes chronic, progressive, debilitating neurologic disease in sheep, often ending in death. Submandibular edema is not a feature.

The external form of caseous lymphadenitis is characterized more by abscess formation in or near major peripheral lymph nodes. Click here to see external caseous lymphadentitis in the parotid lymph node, submandibular lymph node and the prefemoral lymph node.

Images courtesy of Lucyin.