Use of a probiotic formulation in control of Eimeria tenella infection in broiler chickens
The effects of probiotics in broiler chickens were evaluated with respect to feed conversion ratio (FCR), body weights, lesion scores, oocyst output, and cytokine and parasite-specific serum antibody production in birds facing a virulent 'Eimeria tenella' challenge infection. In 2 of 3 trials at 6 days post-infection (dpi), weights of chickens given probiotics twice before challenge were significantly greater than challenged birds without probiotics and feed conversion ratios of probiotic-treated birds were not different from non-challenged birds. Cecal interferon-[gamma] expression differed significantly between challenged and non-challenged birds but not within challenged or non-challenged groups. No significant differences in oocyst output were seen; however, 5 of 6 times probiotic-treated groups shed fewer oocysts. In summary, probiotics showed some evidence of reducing negative performance impact associated with coccidiosis. With further refinement, the use of probiotics may lessen the impact of coccidiosis and potentially reduce the poultry industry's reliance on prophylactic in-feed medications.