Isolation of five species of Eimeria from chickens in Bangladesh

Five species of Eimeria, namely E. acervulina, E. tenella, E. maxima, E. brunetti and E. necatrix were identified in chickens in Bangladesh on the basis of lesions seen at post-mortem examinations of naturally infected birds, and on the dimensions of oocysts and the lesions seen in chicks experimentally infected with single oocyst derived strains. The use of filter top, polycarbonate cages permitted the isolation of strains without sophisticated animal isolators and is appropriate for use in laboratories throughout the developing world. Responses to a questionnaire sent to all known intensive poultry farms suggested that coccidiosis is a major disease. For control, producers rely mostly on management procedures and the tactical use of sulphonamides; in-feed chemoprophylaxis is not widely used. These control measures are unsatisfactory and recent coccidiosis outbreaks were reported from seven of 16 farms. There was evidence of a seasonal incidence in clinical coccidiosis.