Fructans from Renga Renga Lily ('Arthropodium cirratum') Extract and Frutafit as Prebiotics for Broilers: Their Effects on Growth Performance and Nutrient Digestibility

An experiment was conducted to evaluate the effect of dietary water-soluble carbohydrate extract from Renga renga lily ('Arthropodium cirratum') and a commercial product, Frutafit® (both fructans) on the performance, organ weights, ileal digestibility and gut morphology of male Cobb broiler chickens. There were six treatment groups: a negative control with no supplements, a positive control supplemented with 45 ppm Zn-bacitracin, and four test diets each supplemented with Renga renga lily extract or Frutafit at 5 or 10 g/kg diet. Supplementation with low levels of Renga renga lily extract and Frutafit in the diet did not affect productive parameters, whereas the inclusion of a high level of Frutafit had a negative effect on BWG and FI compared with birds fed the negative control diet. The addition of an antibiotic to the diet significantly improved (p<0.05) the BWG and FCR of broilers. Apparent ileal digestibility of dry matter, starch, protein and fat was not affected (p>0.05) by supplementation with both levels of lily extract and the low level of Frutafit. The apparent ileal digestibility of dry matter, protein and fat was decreased (p<0.05) by the high level of Frutafit. The apparent metabolisable energy (AME) of the diets fed the high level of Frutafit was approximately 0.2 MJ/kg DM lower than that of the negative control group. The addition of Zn-bacitracin increased (p<0.05) the apparent ileal digestibility of fat. The relative weight of the liver was higher (p<0.05) in broilers supplemented with the high level of Frutafit than for negative control birds at 14 and 35 d of age. Feeding Renga renga lily extract or Frutafit had no effect on the gut morphology of birds on d 14 and 35. It can be concluded that dietary inclusion of fructans from the two sources used in this study affected broiler performance differently and in a dose-dependent manner.