Effect of plant extracts on growth performance and insulin-like growth factor 1 secretion in growing pigs

ABSTRACTThe objective of the present study is to evaluate the effects of plant extracts on growth performance, nutrient digestibility, and immune blood characteristics in growing pigs. A total of 80 [(Landrace × Yorkshire) × Duroc] pigs with an initial body weight (BW) of 27.31±2.15 kg were used in a 6-wk experiment. Pigs were allotted to one of four treatments (1 - Control (CON) (basal diet); 2 - PE1 (CON + 0.05% plant extracts); 3 - PE2 (CON + 0.10% plant extracts); and 4 - PE3 (CON + 0.15% plant extracts)) in a randomized complete block design according to sex and initial BW. The PE1 and PE2 treatments provided a greater average daily gain than the CON treatment. From weeks 0 to 6 the pigs fed diets PE2 and PE3 showed greater apparent total tract digestibility of dry matter than those fed the CON diet. Pigs fed the plant-extract treatments had a reduction in total mercaptan emission on day 3 compared with control treatment. On day 5, fecal acetic acid content was decreased with increased blood WBC (white blood cells) and lymphocyte counts and serum IGF-1concentration by plant extract supplementation compared with the control treatment. All the results showed a 95% significance level. Supplementation of plant extracts can improve growth performance and nutrient digestibility in growing pigs, decrease fecal gas emission, and increase immune components such as WBC and lymphocytes, and serum IGF-1 concentration in growing pigs.