Abnormal feathering of chicks caused by scirpenol mycotoxins differing in degree of acetylation.

Graded levels of the Fusarium mycotoxins, scirpentriol (STO), 15-monoacetoxyscirpenol (15-MAS), 4,15-diacetoxyscirpenol (4,15-DAS), and 3,4,15-triacetoxyscirpenol (TAS), were fed to chicks until 3 wk of age. The primary wing feathers, which were scored visually on a scale of 1 to 5 using a newly created scoring scheme, were altered in a dose-related fashion by 15-MAS [minimum effective dose (MED) = .5 microgram/g diet], 4,15-DAS (MED = 2 micrograms/g), and STO (MED = 4 micrograms/g) but not by TAS (MED greater than 8 micrograms/g). The minimum growth inhibitory doses were 2 micrograms/g for STO, 15-MAS, and 4,15-DAS and 8 micrograms/g for TAS. The main alteration of the feathers was a frayed and missing web on the medial side of the distal half of the feather. The shafts of the feathers tended to have an accentuated medial curve. These results imply that the feather alterations associated with corn and feed infested with Fusarium spp. might be caused by trichothecene mycotoxins such as the scirpenols.