Submitted to: Avian Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 21, 2006
Publication Date: December 11, 2006
Citation: Jenkins, M.C., Miska, K.B., Klopp, S. 2006. An improved polymerase chain reaction technique for determining the species composition of Eimeria in poultry litter. Avian Diseases. 50:632-635.
Interpretive Summary: Avian coccidiosis is an intestinal disease of poultry caused by protozoa in the genus Eimeria. The disease has been controlled for decades by the medication of feed with ionophore drugs and synthetic chemicals. With increased drug resistance in Eimeria, and consumer pressure to discontinue antibiotic usage in animal feed, producers are increasingly relying on alternative means of controlling coccidiosis. One method that is gaining greater acceptance is oral immunization of day-old chickens with live oocyst vaccines. Decisions on which vaccine to use in a poultry farm will rely heavily on knowing what species of Eimeria are present in the litter. The present paper describes a sensitive technique for determining the species composition of Eimeria in litter by incorporating an internal standard to control for false negative reactions. The utility of this technique was demonstrated using litter samples from a commercial poultry farm
An improved polymerase chain reaction (PCR)-based method for determining the species composition of Eimeria in poultry litter was developed by incorporating species-specific internal standards in the assay. Internal standard molecules were prepared by fusing 7 different Eimeria species-specific ITS1 rDNA primer pairs to a non-Eimeria DNA molecule, and cloning the hybrid DNA molecules into a plasmid. The internal DNA standards were then used in Eimeria-specific ITS1 PCR, and found were capable of detecting E. acervulina, E. maxima, E. praecox, and E. tenella oocysts isolated directly from poultry litter.