Abstract
Red-osier dogwood (Cornus stolonifera; ROD) is rich in phenolic compounds such as ellagic acid, gallic acid, and tyrosol, and these compounds have antioxidative ability. The objective of this experiment was to investigate the effects of dietary supplementation of ROD extract on nutrient digestibility and growth performance of weaned piglets. A total of 56 weaned pigs were assigned to four dietary treatments in a randomized complete block design with 7 replicates per treatment. Each pen had 2 pigs, one male and female. The four dietary treatments included 1) negative control (NC; basal diet), 2) positive control (PC; NC + 0.25% antibiotics), 3) ROD1 (NC + 0.2% ROD extract), and 4) ROD2 (NC + 0.4% ROD extract), and were fed to pigs for a 14-d period. Body weight (BW), and feed disappearance were recorded weekly to determine average daily gain (ADG), average daily feed intake, and gain:feed ratio. Fecal scores were determined twice daily (0900 and 1700) using a numerical score (0 = normal feces, 1 = soft feces, and 2 = diarrhea) for first 9 d. Fecal samples were collected on d 12 to 13 to estimate dry matter (DM) and energy digestibility. On d 14, pigs fed the ROD1 diet had lower (P < 0.05) BW compared to those fed the PC control. Pigs fed diets containing ROD had lower (P < 0.05) ADG than those fed the PC diet. However, there was no difference in overall ADG of pigs between the NC and ROD treatments. The supplementation of ROD had no effect on fecal scores and apparent total tract digestibility of DM and energy for pigs. In conclusion, although the ROD diet showed lower BW on d 14 and lower ADG on overall period, there were no significant differences in apparent total tract DM and energy digestibility among treatments.