Scirpentriol toxicity in young broiler chickens

Scirpentriol (STO) (3 alpha,4 beta,15-trihydroxy-12,13-epoxytrichothec-9- ene), the parent alcohol of the family of acetylated scirpenol mycotoxins produced by several Fusarium species, has been implicated in mixed toxicoses of animals, but there is not a general description of its toxicity in chickens. Dietary STO (0, 2, 4, 8, 16, and 32 micrograms/g feed) was fed to four groups of 10 male day-old broiler chickens for 3 wk. The minimum effective dose (MED) for reducing growth rate significantly (P less than .05) was 4 micrograms/g. The same MED was found for increased serum alkaline phosphatase and relative weight of the gizzard. Unlike literature reports for two other trichothecene mycotoxins, T-2 toxin and diacetoxyscirpenol (DAS), STO impaired feed conversion efficiency but did not alter spleen or pancreas size. The MED of STO for decreases in serum lactic dehydrogenase and aspartate aminotransferase was 8 micrograms/g, but the MED for decreased serum albumin and total proteins and regression of the bursa of Fabricius was 16 micrograms/g. Serum sodium, potassium, and calcium were not altered at the highest dose, 32 micrograms/g, but serum phosphate, uric acid, and cholesterol were decreased by 32 micrograms/g. Serum chloride was increased slightly but significantly (P less than .05) at 16 and 32 micrograms/g. Based on these results, STO toxicosis of chickens can be differentiated from those of T-2 toxin and DAS and its toxicity appears sufficient to warrant further attention.