Utilization of deoxynivalenol-contaminated hard red winter wheat for shrimp feeds

Wheat is used in shrimp feed as protein and energy sources, as well as a nu tritive binder that promotes water stability. However, wheat may be contami nated with deoxynivalenol (DON or vomitoxin) when wet weather conditions pr evail during the growing season. Deoxynivalenol-contaminated wheat was adde d to shrimp diet to obtain DON levels of 0.2, 0.5, and 1.0 ppm. Pelleted di ets were fed 3 times daily until satiation to Pacific white shrimp Litopena eus vannamei. Biological performance (live weight, weekly growth increment, feed conversion ratio, and survival) was determined biweekly for 16 wk. Hi stological characteristics of shrimp were determined on samples obtained af ter 8 and 16 wk of growth. The DON levels in ground wheat, feed mash, pelle ts, and freeze-dried shrimp were determined using thin layer and high perfo rmance liquid chromatography. Deoxynivalenol levels of 0.2, 0.5, and 1.0 pp m in the diet significantly reduced shrimp body weight and/or growth rate. However, the effects of 0.2 and 0.5 ppm DON were manifested at later stages of shrimp growth, and 0.2 ppm DON significantly affected only growth rate and not body weight (P < 0.05). Feed conversion ratio and survival of shrim p fed diets containing 0.2, 0.5, and 1.0 ppm DON were not significantly dif ferent from those of shrimp fed the control diet (0.0 ppm DON). After 16 wk of growth, no DON was detected in freeze-dried shrimp, and no consistent d ifference was observed in the histological organ profiles of shrimp fed die ts containing various levels of DON. Because low levels of DON in the diet can significantly reduce body weight and growth rate of shrimp, feed ingred ients should be monitored for DON.