Influence of dietary plant antioxidant on oxidative status and immune parameters in post-weaning piglet

The aim of the study was to investigate the effect of dietary plant antioxidant in post weaning piglets on oxidative status and immune parameters. At weaning 80 piglets of 8.1 ± 0.2 kg live weight (LW) were allotted to two dietary treatments: control diet (C) and diet supplemented with dietary plant antioxidant (750 g /t feed) titrated at 0.5% of phenylpropanoids, expressed as verbascoside (PPG). The diets were administered ad libitum. Piglets weight was recorded at 0 and 56 d and blood samples were taken from 10 piglets per treatment for oxidative status and immunoglobulin title determination. The assessment of reactive oxygen metabolites (ROMs) in blood serum was performed using the d-ROMs tests (Diacron International® s.r.l. Italy). The serum concentrations of immunoglobulin of class G and A were measured using a commercial kit (pig ELISA quantitation kit; Bethyl Laboratories, Montgomery, TX). Data on growth performance were analyzed by one way ANOVA and data on serum parameters were analyzed by one way ANOVA, with the weaning value entered as a covariate (SPSS Inc., Chicago, IL). Piglets fed C diet shown a lower average daily gain (ADG) (386 ± 9 vs 425 ± 11 g/d; P=0.009) and final weight (29.6 ± 0.7 kg vs 32.1 ± 0.6 kg; P=0.011) than PPG supplemented piglets. No difference was observed in ROMs production between control and treated group (P= 0.115). Piglets fed control diet shown a lower IgG (7.9 ± 0.7 mg/mL vs 16.9 ± 0.7 mg/mL; P<0.001) and IgA concentration (0.6 ± 0.1 mg/mL vs 1.11 ± 0.1 mg/mL; P=0.029) than PPG supplemented piglets. These results support the view that the employed dietary plant antioxidant positively influences growth performance and immune parameters in post weaning piglets.