Two hundred samples (fifty each of,raw milk, cream .Kariesh cheese and processe cheese), collecteu from markets and shops in -different districts in Zagazig citywere examined in this work for incidence of food-poisoning organisms-Coliform organis 8 could be det cted in three s&m-pIes of processed cbeese ana in all sampl.es of raw lIIi.lk,cream and Kariesh cheese.The mean counts (MPN/l 0 g. or 1.)rent products were 17.44 x 102 + 13.06 x12 8 8~ 4.94 x 10 ,74.20 x 10 ~ 48.77 x 10+ 9.59 x 1013 re8pectivel.y.Exawined saapl.es of raw milk~ cream and Karieahchees. proved to be contaminated with E. coli at percen-studied. The obtained results revealed the following.1- Effect on the cellular immune response:A - Totalleukocytic count:The total leukocytic count was not significantly affected duringthe course of the experiment (5 weeks) .The lymphocyte stimulation index was significantly depressedstarting from 3rd day up to the 4t h week post treatment in thenonvaccinated chicken in the presence of the nonspecific mitogenConcanavalin- A, Poke weed , phytohaemagglutinin and the specificantigen NDV vaccine. The same effect started from the 1 st-5th weekpost drug administration in vaccinated chickens when compared with thevaccinated control group.The chemotaxis index of macrophages was similarly affected inboth vaccinated and non-vaccinated groups as previously mentionedwith nonspecific and specific rnitogens .