The Effect of Evening Primrose Extract (Oenotherabiennis) on Growth Performance, Nutrient Digestibility, Blood Characteristics, Faecal Microbiota and Fecal Scorein Weaned Pigs

A 6-week experiment using 100commercial cross-bred piglets, (Duroc × Yorkshire) × Landrace, weaned at 21 d with a bodyweight (BW) of 6.21 ± 0.62 kg was conducted to evaluate the effects of evening primrose extract (EPE) on performance, nutrient digestibility, blood characteristics, fecal microbial concentration and fecal score. Piglets were randomly allocated to five treatments consisting of a positive control containing an antibiotic (33 ppm Tiamulin; PC), a negative control (NC, without antibiotic) and the same diet supplemented with 0.05, 0.1 and 0.2% EPE. In the period 3-6 weeks and overall (0-6 weeks) pigs offered the diets supplemented with EPE exhibited similar performance as those offered the PC diet and tended to grow faster and were significantly more feed efficient than those offered the NC diet. During 3 to 6 weeks, piglets fed the EPE diets had greater ADG (P=0.04) and G/F (P=0.04) than the piglets fed the control diet. Compared with NC, the supplementation of EPE significantly decreased the fecal score of piglets in the first 2 weeks after weaning. Compared with the NC, the supplementation of EPE increased (P =0.02) the DM digestibility at 6 week. The pigs fed the EPE diets had a lower (P=0.01) LDL-cholesterol than the pigs fed the NC diet. Compared with NC, pigs fed EPE diets had a higher Lactobacillus number (P=0.01) and lower E. colinumber (P=0.01) in feces. None of these parameters differed significantly between pigs offered the EPE and PC diets. In conclusion, the results indicate that evening primrose extract supplementation can increase the growth performance, DM digestibility, the population of fecal Lactobacillusspp. and decrease the serum LDL-cholesterol concentration and the population of fecal E. coli. Meanwhile, there is no difference for the growth performance, blood profiles and the fecal micro flora of the piglet between evening primrose extract and antibiotic. As a result, EPE could be a potential candidate of antibiotic alternative.