Effects Of Different Combinations Of Plant Extracts On Growth Performance And Immunity Of Weaned Piglets

In large-scale pig production,early weaning can disrupt redox homeostasis in piglets,resulting in intestinal diseases,decreased growth performance and disease resistance.Plant extracts are rich in biological compounds such as polyphenols,polysaccharides and alkaloids,which possess functions such as antioxidant,anti-inflammatory,improving intestinal microecological environment and immunity.Our previous studies found that Rosmarinus officinalis extract,mangosteen(Garcinia mangostana L)extract and Eucommia ulmoides leaf extract can alleviate diarrhea in piglets.Rosmarinus officinalis extract is rich in rosmarinic acid,which has strong antioxidant and antibacterial effects;mangosteen(Garcinia mangostana L)extract is rich in polyphenols and has anti-inflammatory effect;Eucommia ulmoides leaf extract is rich in polysaccharides and chlorogenic acid,which have the effect of improving immunity,and thus have a potential synergistic effect.Therefore,this study aimed to explore the effects of combinations of three plant extracts on the growth performance and immunity of weaned piglets.The first experiment was designed to explore the effects of dietary supplementation of combinations of Rosmarinus officinalis extract,mangosteen(Garcinia mangostana L)extract and Eucommia ulmoides leaf extract on the growth performance and immunity of weaned piglets.A total of 150 weaned piglets(Duroc×Landrace×Yorkshire)at 21-day-old were selected and randomly divided into 5 groups,with 6 replicates in each group,and 5 pigs in each replicate.The five groups were: control group(basal diet),RME group(basal diet +Rosmarinus officinalis extract 250 mg/kg + mangosteen(Garcinia mangostana L)extract100mg/kg + Eucommia ulmoides leaf extract 150 mg/kg),RM group(basic diet + Rosmarinus officinalis extract 250mg/kg + mangosteen(Garcinia mangostana L)extract 250 mg/kg),RE group(basal diet + Rosmarinus officinalis extract 250 mg/kg + Eucommia ulmoides leaf extract 250 mg/kg),EM group(basal diet + Eucommia ulmoides leaf extract 250 mg/kg +Mangosteen(Garcinia mangostana L)extract 250 mg/kg),the test period was 28 days.The results showed that:(1)there were no significant differences in the average daily gain,feed gain ratio and diarrhea rate among the groups,but the average daily gain in RME group increased by 19.43% as compared with the control group;(2)serum high-density lipoprotein(HDL)content of piglets in RM group was increased significantly,and serum total protein(TP)level of RE group was decreased significantly(P<0.05);while the activity of glutathione peroxidase(GSH-Px)in serum of EM group,and serum total antioxidant capacity(T-AOC)in RM,RE and EM groups were significantly increased(P<0.05),as compared with the control group;(3)serum immunoglobulin Ig M content in RME group was significantly increased,while serum Ig G level in RM group,RE group and EM group were significantly increased(P<0.05),as compared with the control group;(4)serum IL-6 level in RME group,RE group and EM group.serum level of IL-1β in RE group and EM group,as well as serum level of TNF-α in RM and EM group were decreased significantly(P<0.05),as compared with control group.In the second experiment,a dextran sulfate sodium(DSS)induced mouse intestinal inflammation model was used to further explore the effect of combinations of three plant extracts on intestinal inflammation.A total of 60 healthy ICR mice were selected and randomly divided into 6 groups according to body weight,each group had 10 replicates,and each replicate had1 mouse.The 6 groups were control group,DSS group,RME group,RM group,RE group and EM group based on the first experiment.Except the control group,other groups were administrate with drinking water containing 3% DSS to induce enteritis,and the experiment period was 15 days.The results showed that:(1)the final body weight of mice in DSS group was significantly lower than that in the control group,while the final body weight of mice in RME group,RM group and RE group was significantly higher than that in DSS group(P<0.05);(2)DSS decreased significantly the colon length of mice,which was increased in RME group,RM group,RE group and EM group(P<0.05);(3)the ileal villus height of mice in RME group and RM group was significantly higher than that in DSS group(P<0.05).In conclusion,although the pairs of Rosmarinus officinalis extract,mangosteen(Garcinia mangostana L)extract and Eucommia ulmoides leaf extract can improve the antioxidant capacity and anti-inflammatory capacity of piglets,and the combination of three extracts can increase serum Ig M level in weaned piglets;moreover,the combination of three extracts can increase colon length and ileal villus height in the DSS-induced mouse enteritis model.