ENVIRONMENT AND HEALTH Influence of Coccidiosis on Salmonella Colonization in Broiler Chickens Under Floor-Pen Conditions1

ABSTRACT The influence of coccidiosis on colonization of Salmonella typhimurium in broiler chickens under floor pen conditions was studied by semiquantitative methods. Chickens of two groups, unmedicated and medicated with nicarbazin (125 ppm via the feed), were exposed to three species of Eimeria {Eimeria tenella, Eimeria maxima, and Eimeria acervulina) at 2, 3, and 4 wk of age and given S. typhimurium in the feed 2 days later. Salmonella typhimurium was isolated most often (100%) from ceca of chickens exposed at 3 wk of age. Birds in the unmedicated group were positive for S. typhimurium at a higher rate than those in the medicated group. Salmonella typhimurium was detected in livers only in a few unmedicated birds