The influence of a DDGS diet on the development and oviposition rate of Tribolium castaneum (Herbst)

Dried Distillers Grains with Solubles (DDGS) is used in livestock feeds and finishing diets to replace maize or other grains. As more of this product is available to the feed industry, the effect it might have on the vulnerability of animal feed to insect infestation is unknown. This research focused on the influence of old generation DDGS as food and oviposition resource of red flour beetle Tribolium castaneum in contrast with a traditional a flour (90%)/yeast (10%) diet. Larval development was significantly faster (P<0.05) on a flour/yeast diet (19.15±0.16 d) compared to the DDGS (45.44±0.72 d). Both DDGS and the flour/yeast diet had no significant influence on egg hatch or pupation time. These results indicate that this type of DDGS is not as suitable a developmental diet compared to the standard laboratory diet and that the addition of DDGS to animal feeds should not increase feed vulnerability to flour beetle infestation. Additionally, in a no-choice situation, oviposition rate was significantly lower (P<0.05) on DDGS compared to the flour/yeast diet. In conclusion, old generation DDGS is not a good substrate for red flour beetle and thus vulnerability of products to red flour beetle development is not increased with DDGS as an ingredient.