Changes in performance, apparent ileal digestibility and intestinal morphology of broiler chickens fed diets containing sunflower hulls with full-fat canola seed

The effect of addition of sunflower hulls (SFH) as an insoluble fiber on performance and some physiological parameters of broiler chickens fed diets containing full-fat canola seed (CS) was evaluated from 11 to 42 d of age in a 2 × 2 factorial arrangement of treatments. A total of 240 one-day-old broilers (Ross 308) were randomly devoted to 4 treatments, with 6 replicates each and 10 birds per replicate. Treatments were canola oil source (CS, and canola meal plus oil) and sunflower hulls levels (0 and 30 g/kg). During the 11–24 d of age (Grower period), canola oil source and SFH levels had no (P > 0.05) significant interactions on performance. The 30 g/kg SFH inclusion and canola oil resulted in higher body weight gain (BWG) and lower feed conversion ratio (FCR) compared to those fed without SFH and CS diets (P < 0.05). During the 25–42 d of age (Finisher period), in the CS diets, the SFH inclusion reduced (P < 0.05) FCR compared to the diet without SFH. Over the whole trial period, broilers receiving SFH had better (P < 0.05) performance compared to those fed without SFH. Feeding diets with canola oil reduced feed intake (FI) and improved FCR when compared to CS. The inclusion of SFH resulted in a heavier relative gizzard weight than diets without SFH in the canola oil diets, whereas had no effect on this organ in CS diets, resulting in a CS × SFH level interaction (P < 0.05). The inclusion of SFH increased (P < 0.05) ileal organic matter (OM) and crude protein (CP) digestibility in the canola oil diets. In both diets, the inclusion of SFH increased (P < 0.05) the numbers of the Lactobacillus spp. in comparison with diets without SFH, but this effect was more pronounced in canola oil than CS diets. In the CS diets, feeding SFH resulted in lower (P < 0.05) numbers of Escherichia coli in comparison with diets without SFH, while in canola oil diets, it was not influenced. Birds fed SFH showed a greater (P < 0.05) duodenal villus height (VH) and jejunal VH and epithelial thickness (ET) than those fed without SFH. Overall, the current results suggest that whole CS, if supplemented with SFH, can be used in broiler diets without negative effect on the growth performance with beneficial effects on intestinal morphology. Inclusion of canola oil in broiler diets with SFH can benefit nutrient digestibility.