An Outbreak of Caecal Coccidiosis in a Broiler Flock Post Newcastle Disease Vaccination

This study reports a natural outbreak of acute coccidiosis in a broiler flock of 250 birds, in the hot and humid region of Nigeria. The birds which had, on day 10 received infectious bursal disease vaccine started dying a day after the administration of Newcastle disease vaccine. The clinical signs, postmortem findings and response to treatment were used to confirm coccidiosis. The rapid onset of the clinical disease and the high modality rate (33% over a period of 4 days) was considered to have been induced by the Newcastle disease vaccine administration. A diagnosis of sub-clinical coccidosis and institution of prophylactic anticcocidial therapy before Newcastle disease vaccination would have obviated the clinical disease.