Comparative Immunology, Microbiology & Infectious Diseases 30 (2007) 261–268 Effects of Pediococcus- and Saccharomyces-based probiotic (MitoMax s ) on coccidiosis in broiler chickens Sunghyen Lee a , Hyun S. Lillehoj a,à , Dong W. Park a , Yeong H. Hong a , J.J. Lin b a Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, Agricultural Research Service-USDA, Beltsville, MD 20705, USA b Imagilin Technology, LLC, Frederick, MD 21701, USA Accepted 19 February 2007 Abstract Coccidiosis is the major parasitic disease of poultry. In this study, the role of the commercial probiotic MitoMax s which contains Pediococcus acidilactici and Saccharomyces boulardii was evaluated by measuring body weight gain, fecal oocyst shedding, and serum antibody responses as an alternative control method of prophylactic drug against coccidiosis. Day-old broiler chicks were fed regular or probiotic diets supplemented with MitoMax at 0.01%, 0.1%, or 1.0% of diet, and challenged 2 weeks later with 5000 oocysts of either Eimeria acervulina (EA) or Eimeria tenella (ET). Birds fed 1.0% or 0.1% MitoMax-supplemented diets in EA- or ET-infected groups shed less (Po0.05) oocysts than control-infected chickens. Also, chickens fed 0.1% MitoMax-supplemented diet and infected with EA exhibited higher (Po0.001) serum Eimeria-specific antibodies than other groups. These results demonstrate that MitoMax ARTICLE IN PRESS www.elsevier.com/locate/cimid 0147-9571/$ - see front matter r 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.cimid.2007.02.002 Abbreviations: REG, Regular diet; M 0.01, 0.01% of MitoMax s ; M 0.1, 0.1% of MitoMax s ; M 1.0, 1.0% of MitoMax s ; DPI, Days post-inoculation; OD, Optical density à Corresponding author. Tel.: +1 301 504 8771; fax: +1 301 504 5103. E-mail address: hlilleho@anri.barc.usda.gov (H.S. Lillehoj).