The effects of age, litter reutilization, and anticoccidial programs were studied in broilers. The oocyst counts increased with litter reutilization up to third use, and T1 (no anticoccidial drug over the entire 42-day-period) and T4 (anticoccidial medication starting from the first day) showed the highest counts. The scores for Eimeria acervulina increased up to third use of litter and declined by the fourth use. The scores for E. maxima increased from first to second litter use, and from this to third and fourth use. The scores for E. tenella increased from first and second litter use to third litter use, and declined on fourth use. With high coccidial contamination, as in third use litter, the anticoccidial medication starting from the 1st, 7th (T3) and 14th (T2) day of age presented similar results of lesion scores and average weight gain. When coccidial contamination was low or moderate, as in first, second and fourth use litter, the anticoccidial medication starting at 14 days of age tended to result in a better broiler performance. These data suggest that, with low coccidial challenge, as in broilers raised in first use litter and in farms with single bird age, the delayed anticoccidial medication may provide advantages over the full medication starting from the first day of age.
Broiler; coccidiosis; anticoccidial program; performance