Evaluation of broiler chickens rearing parameters in relation to intensity of infection with Eimeria protozoa

The study was aimed to assess the rearing parameters in Ross 308 broiler chickens depending on the intensity of infection with Eimeria protozoa. Two flocks were included in the analysis. One was found to be free from coccidiosis (healthy flock HF) and the other was classified as infected flock (IF). The collected data included the age of the chickens, losses (including falls and culls), body weight, weight gains, and daily feed intake. Additionally, the mean feed intake per kg body weight was estimated and the European Production Efficiency Factor (EPEF) was calculated. The study demonstrated that the presence of Eimeria parasites in the rearing environment of broiler chickens had an impact on the rearing performance by increasing the demand for feed and the percentage of falls and culls during the rearing period, in comparison with chickens from the coccidiosis-free flock. Although they consumed higher amounts of feed, the coccidia-infected chickens were characterized by substantially lower weight gain values. The EPEF value on rearing day 42 in the Eimeria-infected broiler flock was by 103.66 lower than that calculated in the healthy flock.