Protective Effects Of Resveratrol Dry Suspension On Piglets Artificially Infected With Rotavirus

Rotavirus(RV)is the main pathogen causing acute severe viral diarrhea in infants and young animals.The main place of RV infection is intestinal tract,and intestinal health is very important for piglet diarrhea and feed-meat conversion efficiency.Because of the immature immune system and easy to produce oxidative stress,when the piglets were infected with RV,they would suffer more serious damage.At present,there is no specific drug for the viral disease,prevention and control measures just rely on vaccine.Because of the mutation of the virus,the protection rate of the vaccine is reduced,even caused the immune failure.It is also reported that resveratrol has a good therapeutic effect on rotavirus diarrhea.Therefore,this study selected Resveratrol Dry Suspension(RDS)as the object of study to evaluate its effect on piglet diarrhea,immune function,antioxidant stress and intestinal mucosal morphology caused by RV infection.The main research content and the result are as follows: 1 Effect of resveratrol dry suspension on diarrhea of RV-infected pigletsAdd RDS to the base diet of piglets for three weeks and continue feeding after RV infection.The piglets were orally challenged with RV and the piglets weighed on the 0 day post infection(dpi)and 4 dpi,and the daily diarrhea score was recorded.The results showed that on the 2,3,4 dpi,the number of animals with diarrhea in the rotavirus control group was 4/6,6/6 and 5/6.It was believed that RV successfully induced diarrhea in piglets.Because of diarrhea,piglet weight loss in RV group.Compared to RV group,RDS can reduce piglet diarrhea and improve the weight on 4 dpi.The above results showed that the addition of RDS in basal diets can relieve diarrhea caused by RV infection.2 Effect of RDS on immune function and antioxidant stress of infected RV piglets2.1 Effect on immune function: On the 4 dpi.The contents of T lymphocyte subsets in blood were examined by flow cytometry,and the levels of IgG,IgA,TNF-?,IFN-? in serum were examined by ELISA assay.The results showed that RDS can recover the stability of CD4+/CD8+ ratio in the blood compared to RV group,increase the levels of IgA,IgG and IFN-? in serum,and reduce the concentration of TNF-? in serum of piglets infected with RV.That showed the addition of RDS in basal diet could improve the immune function of piglets infected with RV.2.2 Effects on oxidative stress: In order to evaluate the antioxidant capacity of RDS in infected RV piglets,the levels of MDA,T-SOD and GSH-Px activities in serum and liver were examined.The results showed that compared to RV control group,RDS decreased the content of MDA in serum and liver and enhanced the activity of T-SOD and GSH-Px in serum and liver in piglets infected with RV.That showed the addition of RDS to the basal diet in piglets infected with RV can play a role on antioxidant.3 Effects of resveratrol dry suspension on intestinal health of RV infected pigletsThe height of small intestinal villi and the depth of crypt were measured by hematoxylin-eosin staining.The results showed that compared to RV group,RDS can significant increase villi height.There was no significant difference between RV group and RDS groups in crypt depth.But the V/C had increased in RDS groups compared with RV group.That showed RDS had a certain mitigation effect on intestinal mucosa morphological damage caused by RV infection.In summary,adding RDS to the basal diet has a certain protective effect on the piglets artificially infected with RV.RDS has a good effect on piglet diarrhea caused by RV infection,and can improve the immune ability of RV infected piglets,alleviate the oxidative stress induced by RV infection in piglets.It can alleviate the morphological damage of intestinal mucosa caused by RV.