The comparative effect of two chemical coccidiostatic drug on growth performance and oocyst shedding of broilers challenged by Eimeria

In this research 216 day old broiler chicks (Ross 308) were purchased and divided in six groups (each group contains 36 chicks in 3 replicates). Experimental group contain: group 1(Clo+) and 2(Clo-) receive 125 ppm Clopidol in feed throughout the experiment. Group 3 (A+) and 4(A-) received 0/5 gr/kg Amprolium + Ethopabate in feed throughout the experiment. Group 5(positive control) (C+) and group 6(negative control) (C-) received base ration without drug. In day 1, all chicks weigh and 12 chicks for each pen were selected as mean weight of all pens be equal. At day 21 of age, chickens in group 1, 3 and 5 were challenged with with 1.5×105 sporulated oocysts contain Eimeria tenella, Eimeria maxima, Eimeria acervulina and Eimeria necatrix by oral gavage. At day 28 of age, groups A- and Clo- compare to the C- group and group A+ and Clo+ compare to the C+ group had significantly lower weight and weight gain and higher feed conversion rate that showed the negative effect of these drugs on growth performance of birds and also confirm the positive anticoccidial effect of these drugs. However there was no significant difference between A- and cl- and also between A+ and Cl+ groups in growth performance indeces. The result of OPG count showed that A+ and Clo+ groups have significantly lower OPG shedding than C+ group. In addition total mortality were 2 birds that occure in C+ group. OPG count in A+ group at day 7 and 8 post challenge was significantly lower than Clo+ group.