Study On The Response Of Trace Elements On Chronic Oxidative Stress Of Weaned Piglets

Modern livestock and poultry farming are gradually developing towards large-scale,but in the actual production process,due to the influence of many factors such as feeding environment,farming methods,feed ingredients,etc.,livestock and poultry oxidative stress often occurs.Oxidative stress has a negative effect on many aspects of the livestock and poultry body,such as interfering with the body’s normal metabolism,reducing feed utilization,triggering an inflammatory response,resulting in reduced production performance or even death,which will cause certain risks and losses to the breeding industry.Chronic oxidative stress is caused by the imbalance between active oxygen and antioxidants,which is usually associated with the production of chronic oxidative diseases.D-galactose is a naturally-occurring reducing sugar that is ubiquitous in animal bodies or some feed materials.Increasing its intake can cause chronic oxidative stress and mild inflammation of livestock and poultry.Previous tests are often relied on injection of LPS or diquat to create acute oxidative stress to build animal stress models.The piglets died soon after the injection of strong oxidizing reagents,making it impossible to continue the nutritional metabolism test.The oxidative stress in actual production is usually chronic oxidative stress.In this experiment,a model of chronic oxidative stress induced by D-galactose was established through a food-borne approach,aiming to explore the changes of trace elements in the body under chronic oxidative stress.In order to provide a new theoretical basis for nutrition research and feeding management of piglets.First,select32 healthy 21-day-old weaning ternary piglets with an average body weight of 5kg,and randomly divide them into four groups of A,B,C,and D,with 8 animals in each group,and feed 0 mg/kg in proportion to the weight D-galactose diet(Group A),5mg/kg D-galactose diet(Group B),10 mg/kg D-galactose diet(Group C)and 20mg/kg D-galactose diet(Group D),placed in a metabolic cage for 21 days.From this,the optimal amount of D-galactose to construct the model was generated.After that,12 healthy 21-day-old weaning ternary crossbred piglets with similar body weight were selected and randomly divided into two groups,A and B,with 6 animals in each group,placed in a metabolic cage and fed for 21 days.Feed D-galactose-free diet(Group A)and 10 mg/kg D-galactose diet(Group B)according to the proportion of pig body weight.To explore the effect of trace elements on chronic oxidative stress.Results were shown as follows:1)The addition of different concentrations of D-galactose in the diet can affect the growth and development of piglets,significantly reduced the daily feed intake and daily weight gain(P<0.05),and have a significant effect on the heart organ index(P<0.05),other organ indexes.There are certain changes but the difference is not significant(P<0.05).At the same time,according to the change of growth performance,the optimal dose of D-galactose in subsequent experiments is 10 mg / kg.2)The addition of d-galactose in the diet has a significant effect on most of the blood biochemical indicators of piglets.Compared with the control group A,the TP content of the piglets in the experimental group B decreased by 24.41%,ALB content by 23.48%,ALT content by 17.10%,CREA content by 25.00%,AST content by 27.52%,the LDL content decreased by 35.62%,and the differences were significant(P<0.05).ALP content has a decreasing trend(P=0.05),CHOL content has a decreasing trend(P=0.078),TG and HGL content have decreased,but the difference is not significant(P>0.05).3)The addition of D-galactose in the diet can influence the serum antioxidant properties of weaned piglets.Compare with the control group,T-AOC in the mesenteric venous serum of the piglets in the stress group decreased by 11.66%,MDA content increased by 54.18%,GSH content decreased by 13.16%,GST activity decreased by 19.81%,and T-SOD activity decreased by 3.65 %,Cu / Zn-SOD activity decreased by 3.55%,and the difference was significant(P <0.05).At the same time,the activities of Mn-SOD and GSH-Px all changed,generally showing a downward trend,but the difference was not significant(P> 0.05).Carotid serum T-AOC decreased by 28.86%,GST activity decreased by 27.01%,T-SOD activity decreased by 8.63%,Mn-SOD activity decreased by 8.12%,Cu / Zn-SOD activity decreased by 8.87%,and the difference was significant(P <0.05).At the same time,the activities of MDA,GSH and GSH-Px all changed.GSH and GSH-Px showed a downward trend and MDA showed an upward trendency,but the differences were not significant(P> 0.05).The content of MDA in anterior vena cava serum increased by73.56%,T-SOD activity decreased by 3.96%,Cu / Zn-SOD activity decreased by7.98%,and the differences were significant(P <0.05).T-AOC has a downward trend(P = 0.071),GST activity has a downward trend(P = 0.064),at the same time,GSH,GSH-Px,Mn-SOD activities have changed,generally showing a downward trend,but the difference is not Significantly(P> 0.05).Hepatic portal vein serum T-AOC decreased by 18.20%,MDA content increased by 45.51%,GST activity decreased by 24.75%,T-SOD activity decreased by 9.91%,Mn-SOD activity decreased by 12.68%,Cu / Zn-SOD activity Reduced by 9.23%,and the differences were significant(P <0.05).At the same time,the activities of GSH and GSH-Px all changed,generally showing a downward trendency,but the difference was not significant(P> 0.05).4)The addition of D-galactose in the diet can affect the content of trace elements in the organs of weaned piglets.Compared with the control group,the contents of Fe,Mn,and Zn in the liver of the stress group showed significant changes(P<0.05),in which the Fe content decreased by 22.61%,the Mn content increased by 12.85%,and the Zn content decreased by 24.80%,the Cu content also decreased,but the difference was not significant(P>0.05).The contents of Fe and Mn in the kidney showed significant changes(P<0.05),of which Fe content decreased by 9.47%,Mn content decreased by 7.40%,Cu content showed an upward trend(P=0.066),and Zn content showed an upward trend(P=0.089).The contents of Fe,Cu,and Zn in jejunum all changed significantly(P<0.05).The Fe content increased by 49.14%,the Cu content increased by 3.31%,the Zn content decreased by 15.23%,and the Mn content showed an upward trend(P=0.091).The content of Fe and Cu in the ileum showed significant changes(P<0.05),in which the Fe content increased by 18.59%,the Cu content increased by 23.33%,the Zn content decreased by 15.23%,showing a downward trend(P=0.052),and the Mn content did not change significantly.The contents of Fe,Cu and Mn in the colon all changed significantly(P<0.05),in which the Fe content decreased by 35.18%,the Cu content decreased by 24.93%,the Mn content decreased by 54.70%,and the Zn content showed a decreasing trend(P=0.064).5)The addition of D-galactose in the diet can affect the expression of trace element related genes in the liver and jejunum of weaned piglets.Compared with the control group,the expression levels of iron-related SLC40A1,DMT1,and TFR1 m RNA in the jejunum of piglets in the stress group showed an upward trend,while the expression levels of IREB2 and FRRS1 m RNA showed a downward trend.The expression of copper-related CTR1 m RNA in the liver increased significantly(P<0.05),the expression of ATP7 A and ATP7 B m RNA both showed a downward trend,and the expression of ATOX1 m RNA did not change significantly.The expression levels of SLC30A10 m RNA related to zinc / manganese increased significantly(P<0.05),and the expression levels of SLC30A8 and SLC30A14 m RNA all showed an upward trend.The expression level of SOD-1 and SOD-2 m RNA related to copper,zinc,and manganese and related to oxidative stress decreased significantly(P <0.05).In summary,through this test,it was found that adding D-galactose to the diet can reduce the growth performance of weaned piglets,adversely affect the body’s normal nutritional metabolism,and reduce the body’s ability to resist oxidation.The establishment of chronic oxidative stress model with D-galactose can change the content of trace elements in various organs of piglets,affect the expression of trace element transport related genes in organs,and decrease the metabolic efficiency of trace elements in the body.