Tibial dyschondroplasia of chickens induced by Fusarochromanone, a mycotoxin.

Chicks were fed for 3 weeks a practical broiler starter diet amended with fusarochromanone (FC), a mycotoxin. In Hubbard broiler chicks, the highest test dose of FC (75 ppm) suppressed body weight by 33% and humoral response to sheep erythrocytes by 34% to 50%, and increased the incidence of tibial dyschondroplasia (TD) to 100%. The intermediate dose (35 ppm) significantly increased the incidence of TD in both types of broiler chicks (Hubbard and Indian River), but its effect on humoral response to sheep erythrocytes was not consistent across several experiments. A minimum dietary concentration greater than 20 ppm was required to significantly increase the incidence of TD. Excessive dietary copper or zinc (200 ppm) alleviated the effect of FC on TD. However, activities of copper-dependent ceruloplasmin and superoxide dismutase was not affected by FC. Cartilage mineral profiles in FC- or Thiram-induced TD differed from that of 1-day-old hypertrophic embryonic cartilage core (less K and Mn). FC did not induce TD in leghorn chicks.