The Effect Of Different Gelatinization Degree Expanded Corn On The Performance And Fecal Microorganism Of Weaned Piglets

Expanded corn is the process of gelatinization of corn material under the combined action of moisture,heat,mechanical shear,friction,kneading and pressure difference.This kind of high temperature and high pressure treatment can not only improve the flavor of corn feed,but also kill germs,eggs,improve the quality and safety of corn.However,the high degree of gelatinization will increase the grain hardness,reduce the palatability of weaned piglets and reduce the feed intake,so the suitable degree of maize gelatinization will directly affect the growth of weaned piglets.In this paper,the effects of different gelatinization degree corn on weaned piglets’ preference and growth performance,blood index and fecal microorganism were studied.Experiment 1: 144 piglets aged 32 days were selected with similar weight and good health.According to the principle of weight similarity,half of each male and female,In six groups,Four repetitions per group,Repeat 6 pigs each,The test was carried out by double tank method.The ordinary corn,40%,60% and 85% gelatinized corn were added into the feed,Among them,the hardness of common corn,low gelatinization degree(40%),medium gelatinization degree(60%)and high gelatinization degree(85%)were 53.92N、47.57N、63.95N、71.73 N,respectively.Hardness increased significantly as gelatinization increased(P<0.05)。During the test,the double tank of the test is placed at equal distance on both sides of the.The results showed that :(1)Preference test:In this experiment,we studied the predilection of weaned piglets by using the method of double feeding trough.The results showed that weaned piglets with low gelatinization degree(40%)showed high preference,showed no preference for medium gelatinization(60%)diets and highmedium aversion for high gelatinization(85%)and common maize diets.Experiment 2: A total of 144 piglets of 32 days old were selected.According to the principle of weight similarity,half of male and female,divided into 4 groups,each group of 6 repeats,each repeated 6 pigs.The test period is 28 days,In the control group,the diet was common corn group,The experimental diets were expanded corn with low gelatinization(40%),medium gelatinization(60%)and high gelatinization(85%).The results showed that:(1)common maize group(untreated),Although there was no significant difference in the production performance of weaned piglets(P>0.05)(40%),middle gelatinization(60%)and high gelatinization(85%)(P>0.05),However,the average daily feed intake and average daily gain were the highest in puffed corn group(40%).The minimum weight ratio is 1.84,showing relatively good production performance.(2)Effects of blood biochemical parameters in weaned piglets: during the trial period of 1-14 d,There was no significant difference in blood indexes(P>0.05),the test period was 14-28 days,and the contents of total protein and globulin in serum biochemical indexes were significantly different(P<0.05).Differences in other blood indicators were not significant(P<0.05).(3)There was no significant difference in nutrient digestibility,among which the crude protein of low gelatinization(40%)was higher than that of other puffed corn.Experiment 3:The effect of different gelatinization degree S rRNA expanded corn on growth fecal microorganism of weaned piglets was analyzed by 16 high-throughput sequencing techniques.α diversity index indicated that the microbial diversity index Chao1 index and Shannon index(aroma concentration index)of piglets feed with three kinds of gelatinized expanded maize were higher than Control,Among them ECM microbial richness and evenness were higher.Using principal coordinate analysis(PCo A),principal component analysis(PCA)and non-metric multidimensional scale analysis(NMDS)to analyze the differences of microbial community structure between samples,As a result ECM、ECL、ECH the microbial community structure of the three gelatinized expanded maize was stable.and the spatial distribution of Control organisms varies greatly.NMDS results showed that the micro-community structure between Control and ECL samples was relatively dispersed,that is,the diversity of fungi was higher than other gelatinization degree.Species diversity indicated that the highest relative abundance of puffed corn with different gelatinization degree at the phylum level was thick-walled phylum,Bacteroides phylum.To sum up,gelatinization can significantly increase the hardness of granular materials,and there is a positive correlation between the two.low gelatinization degree(40%)maize could improve the feeding preference of piglets,but with the increase of gelatinization degree,the feeding preference decreased.Low gelatinization degree(40%)maize can improve the performance of piglets to some extent,but different gelatinization degree maize has no significant effect on nutrient digestibility of piglets.Expanded corn can regulate the structure of intestinal flora,increase the relative abundance of thick-walled bacteria,and decrease the relative abundance of spirochetes,Proteus and actinomycetes.