Coccidiosis is one of the most important diseases of poultry worldwide. Estimates of the cost to U.S. chicken production alone exceed $350 million dollars annually. Since coccidia-free environments are unattainable in poultry houses it would be beneficial to identify the levels and species of Eimeria present so that severe infection, impaired feed conversion and production losses can be minimized. This Phase I research plan proposed here will assess the feasibility of improving coccidiosis management through tests which combine the use of genus and species specific DNA detection to evaluate the level of infection in a flock via quantitative detection of Eimeria oocysts in fecal samples. Chromagen's proprietary signal amplification technologies will be applied to the synthesis of highly fluorescent DNA probes which hybridize readily and specifically to their respective target sequences. In addition. the sensitivity of time-resolved fluorescence will be utilized to make the assay effective for detection of Eimeria. The Phase I effort will be divided into five areas of investigation: (i) development of procedures for sample collection and reproducible isolation of oocysts from fecal samples; (ii) quantitative extraction of sporozoite DNA; (iii) probe development; (iv) evaluation of the hybridization assax for sensitivity, specificity, and reproducibility, and (v) instrumented detection and data management.Applications:Phase I will result in a quantitative DNA probe assay for detecting pathogen loads of both the genus Eimeria and the three species E. tenella, E. maxima and E. acerl Line which are commercially the most important chicken pathogens. The technology will enable additional quantitative Eimeria tests to be developed to: (i) assess the health hazard to poultry by the individual populations of Eimeria species. (ii) identify critical periods during the production cycle when anti-coccidials should be administered or changed to prevent the spread of infection; (iii) evaluate the efficacy of anticoccidial treatment to determine when drugs can be withdrawn and (iv) reduce losses attributable to other causes, due to incorrect diagnosis of coccidiosis.
