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hemorrhagic lymphadenopathy (Figure 2). Pneumonia and/or gastroenteritis are sometimes observed but are not usually extensive. Atypical forms lacking throat swelling and with extensive pneumonia and/or gastroenteritis have been documented 2, 5, 7 . Potential differentials to consider based on the gross pathology include clostridial myositis, anthrax, salmonellosis, mycoplasmosis (lung sickness) and pneumonic pasteurellosis 3, 5, 7 . Histopathology is non- specific but characterised by lesions consistent with endotoxic shock and capillary endothelial damage 2 . Figure 1: Prominent subcutaneous oedema of the face, submandibular and neck. (Photo courtesy of Dr Willem Burger). and possibly days in damp soil or water 7, 8 . Infection begins in the tonsil and nasopharynx, followed by a bacteraemia with widespread dissemination of bacteria to various body tissues. Proliferation of bacteria in these various sites results in tissue damage due to release of lipopolysaccharides from bacterial cell walls and a host cytokine response with rapidly progressing endotoxaemia. Clinical signs can appear 1-3 days after infection and death can occur within 8-24 hours after first symptoms appear 3, 5, 7, 8. Clinical Signs Most cases of hemorrhagic septicaemia are fatal within 8-24 hours; many animals dying without exhibiting any symptoms. Less fulminant infections are associated with pyrexia, prostration, excessive drooling, dypnea and prominent subcutaneous oedema of the pharyngeal region, which frequently extends to the ventral neck, brisket and face (Figure 1). In these animals where clinical signs are noted, mortality rates are virtually 100%, even with antibiotic therapy 5, 7, 8. Pathology The most common and consistent pathology at post mortem is severe subcutaneous and intra-muscular oedema and cellulitis involving the submandibular region, head, neck and brisket. Fluid is frequently blood tinged and frequently accompanied by Diagnosis Confirmation of diagnosis is by bacterial isolation and subsequent serotyping of Pasteurella multocida isolates. In the live animal heparinized blood samples, nasal swabs and tissue biopsies from the tips of ears are transported on ice to the laboratory for bacterial culture. In freshly dead animals (< 4 hours) a heparinized blood sample/charcoal swab from the heart and nasal charcoal swab should be submitted on ice. Spleen and bone marrow are only contaminated late in the post mortal process and so serve as excellent post mortal sample sites for culture. In atypical cases lung, intestine and mesenteric lymphnode should be included 5, 7. Treatment and Prevention Although some antimicrobials are effective Figure 2: Severe blood tinged subcutaneous oedema with associated hemorrhagic lymphadenopathy (white arrow). 2017 MAY 5