An outbreak of Eimeria necatrix coccidiosis in breeder pullets: analysis of immediate and possible long-term effects on performance.

Coccidiosis caused by Eimeria necatrix was diagnosed in a flock of 17,640 broiler breeder pullets at 18 weeks of age on a new farm. Mortality and morbidity was excessive in both hens and males, resulting in 10.1% fewer hens capitalized and 15.56% fewer males. Egg production was lower by 4.51% during weeks 30-40 of age in comparison with other flocks of about the same age. Estimates of the cost of replacement of death losses and culls, the direct effect on the cost of the flock, and the increased cost of production amounted to $27,234.