The effects of including increasing doses of stevia and neohesperidine dihydrochalcone on feed preference in young piglets

摘要

Two double-choice feeding experiments were conducted to study the effect of stevia extracts (SE) and neohesperidine dihydrochalcone (NHDC) on feed preference in piglets. Pigs (14 to 35 d postweaning) were offered a series of double choices between a common reference diet (R, containing 4% sucrose) and experimental diets (containing 4% maltodextrin plus different doses of SE and SE+NHDC). In Exp. 1, the doses of SE were 0, 100, 200, 300, 400, and 500 ppm (T1 to T6); in Exp. 2, the dose of SE was 150 ppm plus 0, 2, 3, 4 or 5 ppm NHDC (T1 to T5). The two diets (R and T1 to T6) were offered to pens of 3 piglets following a choice test protocol (n = 12 for each comparison). Feed intake and preference (relative intake of a given feed when offered as a double choice with a reference feed) for each diet were calculated. In Exp. 1, piglets in the comparisons of 0 and 100 ppm SE showed no preference or avoidance when contrasted with the R diet. However, feeds with higher levels of SE (200, 300, and 500 ppm SE) were avoided (preferred less than 50%). In Exp. 2, diets with 150 ppm SE plus 0 or 5 ppm NHDC were not preferred or avoided relative to the R diet, whereas diets with either 2, 3, or 4 ppm NHDC were preferred (P 0.05) when contrasted with the R diet, following a quadratic response (P = 0.08). In conclusion, the combination of 150 ppm SE with 2-4 ppm NHDC in starter diets increases feed intake and preference (relative to 4% of sucrose) as compared to diets including only SE.