Date of Graduation


Document Type


Degree Name

Master of Science in Poultry Science (MS)

Degree Level



Poultry Science


Robert F. Wideman, Jr.

Committee Member

Nicholas B. Anthony

Second Committee Member

Dan J. Donoghue


Biological sciences


Growing broilers on wire flooring provides an excellent experimental model for reproducibly triggering significant levels of lameness. In Pilot Study #1 using broilers from Line C grown on wire flooring, adding the Biomin probiotic PoultryStar® to the feed reduced the percentage of lameness by half when compared with broilers that received the control diet alone. In Pilot Study # 2 using broilers from Line B grown on wire flooring, adding the PoultryStar® probiotic reduced the percentage of lameness to 8% when compared with 28% lameness in broilers that received the control diet alone. The objective of this study was to conduct a replicated experiment to determine if probiotics consistently reduced the incidence of lameness in broilers reared on wire flooring. Male broiler chicks from Cobb-Vantress Line B were placed at 1 day of age in pens having flat wire flooring within environmental chambers 1 through 10 inside the Poultry Environmental Research Lab at the University of Arkansas Poultry Research Farm. On day 14, birds were culled to 50 per pen, yielding a density of 1ft²/chick. A corn and soybean meal-based diet formulated to meet minimum National Research Council standards (1994) for all ingredients was provided ad libitum as the control feed. Broilers in chambers 1, 3, 5, 7 and 9 were provided the control feed while chambers 2, 4, 6, 8 and 10 were provided the same feed mixed with the probiotic throughout the experiment (50 lbs of control feed blended with 12.5 g PoultryStar® probiotic). The birds in all pens were "walked" and observed for lameness every two days starting on day 15 and continuing until the end of the experiment on day 56. Birds unable or unwilling to walk were diagnosed as "clinically lame" and humanely euthanized with CO2 gas. They were then necropsied to assess sub-clinical lesion incidences including femoral head separation, femoral head transitional degeneration, femoral head necrosis, tibial head necrosis, and tibial dyschondroplasia. Findings from the study indicate that for broilers grown on wire flooring, diets containing the probiotic PoultryStar® consistently reduced the incidence of lameness when compared with birds fed the control diet alone.