A total of 100 diseased living chickens were collected from different farms in Gharbia Governorate and
were subjected to clinical and postmortem examination as well as for isolation and identification of E.
coli and salmonella from tissue samples including spleen, heart, liver, intestine and lungs . The
predominant isolates were Salmonella Entertidis and E.coli O78.An experiment was conducted on 120
one day old chicks (avian 48) then divided into 6 groups to evaluate the effect of supplementation of20g
/1000 bird/day in drinking water Synbiotic (Poultry star^®)on immune response of normal and
experimentally infected chicks with salmonella and E.coli . First group is acontrol negative group (G1),
second group Synbiotic supplemented group (G2), third group infected with Salmonella Entertidis (G3)
, fourth group infected with Salmonella Entertidis and supplemented with Synbiotic (G4), fifth group
infected with E.coli O78 (G5) and the last group infected with E.coli O78 and supplemented with
Synbiotic (G6). Significant decrease in phagocytic activity , phagocytic index and weight of bursa of
Fabricius, thymus and spleen in infected groups were observed, but significant increase in HI titer,
phagocytic activity , phagocytic index and weight of bursa of Fabricius,thymus and spleen in Synbiotic
supplemented groups were observed