Molecular detection of Eimeria species and Clostridium perfringens in poultry dust and pooled excreta of commercial broiler chicken flocks differing in productive performance.

Necrotic enteritis and coccidiosis are the most economically detrimental enteric diseases of broiler chickens. This study aimed to investigate the association of DNA load of Clostridium perfringens, netB, and five Eimeria species (E. brunetti, E. maxima, E. necatrix, E. acervulina and E. tenella) in poultry house dust and pooled excreta with flock productive performance. The dust and pooled excreta from the floor were collected weekly at days 7, 14, 21, 28 and 35 of chicken age from 16 flocks of eight farms from two Australian integrator companies. The farms were ranked as high or low performers by each integrator according to the production performance of studied flocks. Eimeria tenella and necatrix were not detected in any farm while E. brunetti was detected in a low-performance farm and netB was detected in a high-performance farm. C. perfringens, E. acervulina and E. maxima DNA were detected on all farms with no significant differences in DNA load between high and low-performance farms or companies. The lack of association of pathogen DNA load and farm performance is possibly due to overall low to moderate pathogen DNA load detected in this study. Further studies on a larger number of farms are needed to determine whether these population level measurements of key pathogens based on PCR detection of nucleic acids are correlated with performance variables.