Lesion scores in the upper(P = 0.003)or middle (P = 0.018)region of intestine differed significantly between treatments,but there was no significant effect between the experimental groups in cecal region The unchallenged birds had lower lesion scores in upper region of small intestine than PC group(0.78 vs. 2.16;P = 0.003).Challenged birds fed diets supplemented with Diclazuril or 500 ppm oregano oil had similar coccidiosis lesion scores in upper region of small intestine when compared to unchallenged group,and differences between PC group and challenged birds received 300 ppm oregano oil was not significant. Lesion scores values of the unchallenged group in middle region of intestine were lower than these of PC(0.84 vs. 1.93; P = 0.018),and the other supplemental groups had same lesion sas the unchallenged group. The overall mean lesion scores of PC group were the highest and significantly different from all the other
treatments (P = 0.001),and challenged broilers fed diets containing 500 ppm oregano oil were similar to unchallenged group.