Evaluation Of Application Effect Of Nano Vitamin E In Broilers

Vitamin E plays an important role in improving the antioxidant capacity of the poultry organism,preventing diseases,inhibiting inflammatory reactions,regulating immune function and improving the quality of poultry meat,and is an indispensable fat-soluble vitamin for poultry farming.Only about 30%-35%of the vitamin E added to poultry feed is actually digested and absorbed,with a bioavailability of about 50%,which is even lower when the poultry is under disease or impaired lipid absorption.This study was designed to investigate the absorption characteristics of nanosized vitamin E and its effects on production,antioxidant and immunity in AA broiler chickens through a 4-part experiment in order to provide a basis and data to support the development and application of nanosized vitamins.Experiment 1:Nanosized vitamin E pharmacokinetic properties in broiler chickensSixteen 35-day-old AA white feather broilers were selected and randomly divided into 2groups（n=8）:nanosized vitamin E（NV）group and regular vitamin E（CV）group.The blood was collected 1 h before and 1.5,1.5,1.5,1.5,3,3,3,6,6,6,6,12 h after injection,and the plasma vitamin E concentration was measured at different time points with no feeding during the sampling period.The results showed that after oral infusion of NV and CV,the plasma vitamin E concentration increased sharply with time and then decreased slowly,and NV and CV maintained a synchronous dynamic tendency;compared with the CV group,the absorption rate of NV group was much higher than that of CV group at 4 h and 5.5 h after infusion and reached a significant difference（P<0.05）,and the plasma vitamin E concentration remained higher at 8.5 h,11.5 h,14.5 The higher blood concentration was maintained at 8.5 h,11.5 h and 14.5 h.The drug-time curve showed that the NV group reached a higher maximum blood concentration than the CV group（P>0.05）.The area of the drug-time curve AUC_（0-∞）,peak concentration C_max,mean residence time MRT_（0-∞）and terminal elimination half-life t_1/2z were greater in NV than in CV（P>0.05）when the relevant parameters were calculated using DAS3.0.Fitting using the software system yielded that NV was 146.52%of the relative bioavailability of CV.This suggests that NV has a faster rate of absorption and greater absorption in vivo,increasing the vitamin E blood circulation abundance and improving the bioavailability of vitamin E,which may have an impact on the effect of vitamin E action.Experiment 2:Effect of nanosized vitamin E on antioxidant function in broiler chickens under oxidative stress modelBased on experiment 1,an oxidative stress model was constructed to fit the stress state of broiler scale farming to investigate the effect of nanosized treatment on the antioxidant function of vitamin E in broilers and on meat quality.Forty-eight AA white-finned broilers with similar body weight at 28 days of age were randomly divided into four groups:nano-vitamin E 30 IU/kg（NV30 group）,regular vitamin E 30 IU/kg（CV30 group）,nano-vitamin E75 IU/kg（NV75 group）and regular vitamin E 75 IU/kg（CV75 group）;each treatment group was divided into groups A and B（n=6）,were injected subcutaneously with dexamethasone sodium phosphate（DXMS）solution and the same volume of saline at 3 mg/kg body weight abdomen on day 29,31 and 33 of age,respectively.Serum was collected at 1 h,4 h,8 h and42 days of age to determine T-AOC,GSH-Px,SOD activity and MDA content after completion of injection at 33 days of age.The drip loss,meat color and shear force were determined on the day of slaughter and on the 3rd day after slaughter by taking the leg and pectoral muscles at 42 days of age.The results showed significant differences（P<0.05）for T-AOC and MDA at 4 h and 8 h.T-AOC increased and then decreased with time after injection,reaching a maximum at 4 h.However,it decreased and then increased in the NV30 group,reaching a peak at 8 h and significantly different from the CV group（P<0.05）.At 1 h after injection,MDA was higher in the NV group than in the CV group but there was no difference（P>0.05）,and the MDA content gradually increased with the extension of the time point;this phenomenon was rapidly reversed in the NV group after 4 h and 8 h to reach a significant difference（P<0.05）.There was no significant difference in the trend of GSH-Px between the NV and CV groups（P>0.05）.Compared with the NV30 group,the NV75 group significantly reduced the leg muscle water loss rate（P<0.05）;compared with the CV and NV30 groups,the NV75 group significantly reduced the leg muscle L*value on day 0（P<0.05）,and compared with the CV group,the NV group significantly increased the a*value on day 3 after slaughter（P<0.05）.The dynamic changes of the whole antioxidant index reflected that NV can quickly respond to acute oxidative stimuli,reverse the peroxidation state of the broiler organism and maintain the redox homeostasis of broilers,and the performance of NV antioxidant capacity is closely related to its metabolic kinetic process.Experiment 3:Effect of nanosizing on the uniformity of vitamin E dispersion in broiler intestinal food surimiIn this experiment,the effects of nanosized treatment on the variability characteristics of vitamin E intestinal dispersion and lipid-soluble absorption processes were investigated on the basis of experiments I and II.The concentration of vitamin E in the chyme at the anterior（F）,middle（M）and posterior（L）sites of the duodenum,jejunum and ileum was determined in 42-day-old AA broilers in the CON,NV30,NV75 and CV75 groups（n=6）,respectively.The results of the analysis of vitamin E variation at different loci showed that vitamin E nanosized treatment and addition levels did not cause changes in their absorption sites;the differences in variation were smaller in the anterior duodenum（D-F and D-M）and the posterior jejunum（J-L）and decreased sharply in the posterior jejunum;there was no significant linear trend in the degree of variation of chyme vitamin E with vitamin E addition levels at different loci in the small intestine.The variation in the NV group was smaller than that in the CV group throughout the intestine,and NV was more evenly dispersed in the broiler small intestine.Experiment 4:Effect of nanosized vitamin E on broiler productionBased on the above experiments,the effects of feeding NV to AA broilers on production performance,immunity and antioxidants were investigated.A total of 768（8×6×16）1-day-old AA broilers were selected.The control group（CON）was fed the basal diet,groups 2 to 6were fed the test diets supplemented with 15,30,45,60 and 75 IU/kg NV,and groups 7 to 8were fed the test diets supplemented with 30 and 75 IU/kg CV,respectively,for 42 days.The results showed that the NV30 group significantly reduced FCR from 22 to 42 days of age and from 1 to 42 days of age（P<0.05）;feeding the same level of 30 IU/kg and 75 IU/kg vitamin E did not significantly affect the immune organ index at 21 days of age in the NV and CV groups（P>0.05）,but the NV75 group significantly increased the bursal index at 42 days of age.Spleen q PCR results showed that the expression of TGF-βm RNA was significantly lower in the NV75 group at 21 and 42 days of age compared to the CON and CV groups（P<0.05）;IL-6 m RNA expression was significantly lower in the NV30 and NV75 groups compared to the CON group;and feeding the same level of 30 and 75 IU/kg vitamin E,compared to the CV group.NV group did not significantly differ on T-AOC,MDA,SOD and GSH-Px at 21days of age（P>0.05）,but significantly increased the enzymatic activity of SOD（P<0.05）.Therefore,NV can replace CV as a source of vitamin E in poultry diets and is more effective than CV in terms of broiler performance,antioxidant and immunity;the addition of 30 IU/kg nanosized vitamin E to broiler diets was the most effective in terms of comprehensive production data,antioxidant and immunity indices.In conclusion,vitamin E nanosized treatment has better metabolic kinetic characteristics,improves its relative bioavailability and has a positive impact on the immune and antioxidant functions of vitamin E on broiler chickens,NV can replace CV as a source of vitamin E in poultry diets,and it is advisable to add 30 IU/kg of nanosized vitamin E to broiler breeding diets.