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Line 42: |
| **K antigens prevent phagocytosis or mimic host antigens and resist complement | | **K antigens prevent phagocytosis or mimic host antigens and resist complement |
| **Fimbriae permit adhesion to mucosal surfaces | | **Fimbriae permit adhesion to mucosal surfaces |
| + | **May enter blood to cause septicaemia |
| + | *Clinical infections: |
| + | **Avian colibacillosis: |
| + | ***Septicaemia in newly-hatched chickens |
| + | ***Infection enters via faecal contamination of the egg surface or via the ovary of the hen |
| + | ***Infection enters via the respiratory tract |
| + | ***A bacteraemia develops |
| + | ***Acute colisepticaemia, subacute fibrinopurulent serositis or chronic granulomatous disease of the viscera |
| + | ***Occurs in older birds via inhalation of ''E. coli'' in dust; respiratory infection spreads to the blood to cause acute colisepticaemia |
| + | ***Airsacculitis, pericarditis and perihepatitis during acute phase |
| + | ***Often secondary to virus or mycoplamsa infection or environmental stress |
| + | **Colisepticaemia: |
| + | ***Systemic disease in young calves, piglets, foals, lambs |
| + | ***Penetration of intestinal mucosa and entrance into the blood |
| + | ***Invasive strains survive the host defences |
| + | ***Virulence related to adhesive properties, complement resistance and ability for iron aquisition |
| + | ***Ammonia, dust, viral infections and temperature changes enhance likelihood of disease |