[Coccidiosis in broiler chicks: the prevalence of oocysts in feces in relation to necropsy findings in (sub)clinical coccidiosis and the effect of nicarbazin on these findings].

Faecal samples were also collected from broiler farms presenting birds for autopsy. 126 Samples were examined, using two methods. Oocysts were detectable 3.5 days previously on an average before the presence of coccidiosis was determined at autopsy. Of the faecal samples 65.9 per cent were positive, and 46.0 per cent of the findings at autopsy were positive for coccidiosis. Examination of the faeces showed that more cases of mixed infection were present than could be concluded from autopsy. The largest number of oocysts was observed in E. acervulina infection, though large numbers of oocysts were also detected in cases of mixed infection. Treatment with nicarbazin during te first three weeks of life was found to delay the appearance of coccidiosis. The frequent use of withdrawal periods in the administration of anticoccidial drugs in view of 'thinning' showed high excretion rates.