Clinicopathological studies on chickens immunized against coccidiosis

Control of coccidiosis in chickens has relied up on managerialmeasurements and the prophylactic use of coccidiostatic drugs with theemergence of Eimeria strains that are resistant to those drugs. The use ofcommercially available vaccines has increased.The present work was performed to study the cellular and humoralimmunity of infected chickens with coccidiosis, vaccinated once andinfected of previuosly vaccinated chickens. Also to quality the inheritedmaternal immunity that transferred to hatching chickens from hensvaccinated against coccidiosis.The study included 2 experiment. The first one comprised 75~hickens were hatching from non vaccinated hens against coccidiosis.The chickens were subdivided into 4 groups. The I” group kept ashealthy control, the 2nd group infected with 10000 mixed sporulatedEimeria oocysts at 4 weeks old, the 3cd group vaccinated once withCocciVac B at one day old and the 4th group vaccinated once withCocciVac B at one day old then infected with 10000 mixed sporulatedEimeria oocysts at 4 weeks old. The second experiment comprises 60chickens hatching from vaccinated hens against coccidiosis, andsubdivided into 3 groups. The 5th group kept as healthy group, the 6thgroup early infected at 2 weeks old with 10000 mixed sporulated Eimeriaoocysts and the 7th group were late infected at 4 weeks old with the samedose. Chickens in all groups were weighted weekly and feedconsumption for each group was calculated during the experimentalperiod. The cellular immune responses were studied at the end of eachweek from the 2nd tiIJ the 6th week.