Effects Of Dietary Different Supplemental Patterns Of Copper,Iron,Zinc And Manganese On The Regulation Of Nutritional Process Of Piglets

High doses of trace elements are often added to animal feed in intensive breeding enterprises,and the trace elements in feed raw materials are often ignored.The utilization rate of trace elements by animals is very low,so animals will discharge most of the trace elements into the soil through feces,and this led to serious soil problems.Under the trend of the expansion and centralized development of global animal husbandry,a reasonable mode of adding trace elements is needed in order to respond to the development of national environment-friendly animal husbandry.In this experiment,different supplemental modes of copper,iron,zinc and manganese were added to the diet to analyze their effects on growth performance,fecal trace element content and serum biochemical indexes.The purpose of this study is to provide data basis for the use of dietary trace elements and environmental protection breeding of piglets based on growth performance.This study is composed two trails.Experiment 1 Effects of feed raw material trace element analysis and trace element addition model on growth performance and fecal trace element concentration of pigletsIn this experiment,400 PIC commercial pigs aged 56 days were randomly divided into4 groups(5 replications in each group,20 pigs in each group).Before preparing the diet,the raw materials of the experimental feed and the basic diet were sampled and the concentrations of trace elements copper,iron,zinc and manganese were determined.Through the measured values of trace elements in feed raw materials and the calculation of the treatment addition,we divided into four groups: the control group was fed with basic diet(without exogenous copper,iron,zinc and manganese,BD);the diets of three treatments were formulated according to the following standards: the Agricultural Industry Standard of the people’s Republic of China(NY/T65-2004,IS);the Danish Nutrition requirement Standard(SEGES,26th edition,2018,DS)and commercial diet(CD).IS and DS diets: by calculating the multiples of the relative stander needs of copper,iron,zinc and manganese measured in the basic diet exceeding the recommended elements,other three elements are supplemented in the form of sulfate according to this multiple,among them: The IS diet was BD+4.76,85.29,95.05 and 0 mg/kg copper,iron,zinc and manganese;the DS diet was BD+4.76,90.29,85.05 and 35.99 mg/kg copper,iron,zinc and manganese,and the CD was BD+104.76,90.29,85.05 and 49.99 mg/kg copper,iron,zinc and manganese.The pre-feeding period was 7 days,and the trial period was 28 days.The results showed that: 1)compared with BD,different supplemental patterns did not cause significant difference on ADFI,ADG,FCR,diarrhea rate,death rate(P > 0.05).2)at 69 days of age,compared with the BD,the concentrations of copper,iron and manganese in feces in the CD were significantly high(P < 0.05);DS significantly increased the concentration of iron and manganese in feces(P < 0.05);IS also significantly increased the concentration of iron in feces(P < 0.05).At 83 days of age,compared with BD,other treatments significantly increased the concentration of zinc in feces(P < 0.05);CD significantly increased the concentrations of copper and manganese in feces(P < 0.05);DS significantly increased the concentrations of copper,iron,zinc and manganese in feces(P < 0.05).The results showed that dietary copper,iron,zinc and manganese supplementation did not cause significant differences in performance,diarrhea rate,death rate and organ index of piglets,but feeding with the basal diet reduced the use of trace elements and fecal pollution.Experiment 2 Effects of trace element addition model on trace element metabolism and antioxidation in pigletsIn this experiment,slaughtering piglets at 69 days old and 83 days old,blood,liver and kidney samples of piglets were collected,and mucosal samples of duodenum and jejunum of piglets were collected.The purpose of this part was to study the effects of different dietary trace elements on the deposition of trace elements in serum and tissue,the expression of metal ion transporter mRNA in duodenum and jejunum and the antioxidant activity of liver in piglets.The results showed that: 1)There was no significant difference in the concentrations of copper,iron,zinc,and manganese in serum in the experimental group(P >0.05),but the concentrations of trace elements in liver and kidney in the BD were the lowest compared with other experimental groups.2)At 69 days of age,compared with the BD group,different supplemental patterns did not cause significant difference in the mRNA expression of ZIP1,ZnT5,DMT1,FPN1,and MT3 in the duodenum(P > 0.05).Different supplemental patterns did not cause significant difference in the mRNA expression of ZIP1,ZnT5,Ctr1,DMT1,FPN1,and MT3 in the jejunum(P > 0.05).At 83 days of age,compared with the BD group,different supplemental patterns did not cause significant difference in the mRNA expression of ZnT5,Zip1,Ctr1,DMT1,FPN1,and MT3 in the duodenum and jejunum(P > 0.05).there was also no significant difference in the expression of ZnT5,FPN1 and MT mRNA in the jejunum between the experimental group and the BD(P > 0.05).3)at69 and 83 days of age,there was no significant difference in the mRNA expression of Cu Zn-SOD and Mn-SOD in the liver of the four experimental groups(P > 0.05).The results showed that adding high dose of trace elements to the diet could significantly increase the content of trace elements in tissue.However,it had no effect on the transporter of trace mineral elements in intestinal tract and the expression of superoxide dismutase in liver.The results showed that no exogenous trace elements in the diet could maintain the growth performance of 56-83-day-old piglets and had no negative effect on the subsequent growth,reduce the discharge of trace elements in feces and reduce the waste of trace element resources.it is helpful to the sustainable development of environment-friendly animal husbandry.