Tissue sections of S. aureus and /or E. coli infected non treated birds (7 DPT) (HandE, X 200) showing. A: E. coli infected bird: kidney hemorrhages accompanied with coagulative necrosis of some tubules (head of arrow). B: E. coli infected bird: s.c severe suppurative inflammation with marked accumulation of heterophils and mononuclear cells in s.c fatty tissue (head of arrow). C: E. coli infected bird: spleen hemorrhages (head of arrow).  D: S. aureus infected bird: perivascular edema of the pulmonary artery (head of arrow). E: S. aureus + E. coli infected bird: muscle edema (head of arrow).