Influence of high levels of pyridoxine on twisted legs in broilers

Three experiments were conducted using commercially available broiler chicks to study the influence of high levels of pyridoxine on incidence of twisted legs. Chicks were grown in wire floored battery brooders to two weeks of age when they were weighed and visually scored for twisted legs. Supplementation of a diet containing 2.2 mg synthetic vitamin B6/kg with 10 and 20 mg/kg pyridoxine resulted in a significant decrease (P less than or equal to .05) in incidence of twisted legs in Experiment 1. In Experiment 2, supplementation with 30, 60, or 100 mg/kg numerically reduced incidence, but the differences were not statistically significant. Incidence of twisted legs was significantly increased by injecting chicks with .5 ml physiological saline at 1 and 7 days of age in comparison to noninjected controls. Including 10 mg pyridoxine HCl in the saline reduced the incidence but it was still numerically higher than the noninjected controls. Factors other than vitamin B6 nutrition appear to play a more important role in the etiology of twisted legs in broiler chicks.