Effects Of Acidifiers On Growth Performance,physiological Indicators,Oxidative Stress Level,and Intestinal Flora Of Weaned Piglets

In most intensive pig farms piglets are weaned at 21 to 28 days of age.However,the function of piglet’s digestive system is not well developed at this age.For example,the secretion of gastric acid is insufficient and the digestive enzyme activity is low,resulting in incomplete digestion of the protein in the feed.After entering the intestine,it would cause abnormal bacteria to multiply,which leads to diarrhea and decreases the growth performance in the piglets.In addition,the changes of the environment and feed bring stresses to piglets after weaning.It makes the piglets susceptible to pathogen invasion and infection,which causes early weaning syndrome and a decrease of growth performance.Previous studies have shown that acidifiers can induce and stimulate taste buds and increase feed intake in livestock and poultry.Acidifiers can improve feed utilization,promote animal growth and immunity,improve intestinal microflora and reduce the occurrence of diarrhea of animals.Therefore,in this study,the effects of three different organic compound acidifiers on the growth performance,diarrhea rate,blood physiological indicators,oxidative stress level and fecal microbial diversity of weaned piglets were investigated.In this experiment,a total of 400 healthy 28-day-old weaned piglets were randomly divided into 4 groups: acidifier 1(19% formic acid,19% acetic acid,3.5% propionic acid,and 15% lactic acid);acidifier 2(22% formic acid,16% acetic acid,and 4% propionic acid);acidifier 3(22% formic acid,16 acetic acid,4% propionic acid,and 0.5% steviol glycoside);and control group,no acidifier added.Acidifier 1 contained 15% lactic acid,acidifier 2 did not contain lactic acid,and acidifier 3 contained a sweetener(0.5% steviol glycoside)on the basis of acidifier 2.There were 4 replicates(pen)in each group,and 25 piglets per pen.The trial lasted for 35 days.At the 18 th and 35 th days of the experiment,64 pigs(4 pigs per pen)were randomly selected to collect blood and fresh feces.The results are as follows:1 Effects of acidifiers on growth performance and diarrhea rate of weaned pigletsThe aim of this study was to evaluate the effects of adding different acidifiers in drinking water on the average daily gain(ADG),average daily feed intake(ADFI),feed/gain(F/G)and diarrhea rate of weaned piglets.The results showed that:(1)the ADG and ADFI of weaned piglets in the group 1 were significantly greater than the control group and the group 3(P < 0.05);(2)there was no significant difference in the piglet diarrhea rate and the survival rate among the four groups(P > 0.05).There was no significant difference in the whole trial period(P > 0.05).Compared with the control group,the acidifier 2 had a tendency to increase the survival rate of piglets.(3)During the entire test period,the economic benefit of piglet breeding in the group 1 was the highest,and the control group was the lowest.2 Effects of acidifiers on blood physiological indicators and oxidative stress level of weaned pigletsThe objective of this experiment is to study the effects of adding different acidifiers in drinking water on the blood physiological indexes and oxidative stress indexes of weaned piglets.The results showed that:(1)At the 18 th day,Neu of pigs in the group 1 and group 2was lower than that of pigs in group 3(P < 0.05);Neu%,HCT and MCV of pigs in group 1and group 2 were less than those of pigs in the control group(P < 0.05);MCH,MCHC and RDW-SD of pigs in the group 1 and group 2 were greater than those of pigs in the control group(P < 0.05);Mon and Mon% of pigs in the group 1 were greater than those of pigs in the other three groups(P < 0.05);Eos,RBC,MPV and PDW of pigs in the group 1 were less than those of pigs in the control group(P < 0.05);Eos% and RDW-CV of pigs in the group 1 were greater than those of pigs in the control group(P < 0.05);Lym% was greater in the group 2 than in the control group(P < 0.05);the PLT was greater in the group 2 than in the group 3(P < 0.05).At the 35 th day,WBC of group 1 and group 2 was greater than those of pigs in the group 3(P < 0.05);Eos was greater in the group 1 and group 2 than in the control group(P < 0.05);Eos% was greater in the group 1 and group 3 than in the control group(P < 0.05);Mon was greater in the group 1 than in the control group(P <0.05);Lym was greater in the group 2 than in the group 3(P < 0.05);PLT,PCT and PDW were greater in the group 2 than in the control group(P < 0.05);Bas,Bas%,RBC,HGB and HCT of pigs in the group 3 were less than those of pigs in the control group(P < 0.05);MPV was greater in the group 1,2 and 3 than in the control group(P < 0.05).(2)At the18 th day,SOD content of pigs in the group 1 and group 2 was less than that of pigs in the control group(P < 0.05).T-AOC levels were greater in the group 2 and group 3 than in the control group(P < 0.05).At the 35 th day,MDA content was less in the group 1 than in the group 3(P < 0.05).3 Effects of acidifiers on the diversity and abundance fecal microbes of weaned pigletsThe purpose of this experiment was to study the effects of adding different acidifiers in drinking water on the diversity and abundance of fecal microbes of weaned piglets.The results showed that:(1)At the 18 th day,the shannon index of group 2 was less than that of group 3(P < 0.05).At the 35 th day,the observed＿species and chao1 indexes of group 3were less than those of the control group(P < 0.05);the simpson index of group 1 was less than that of the control group(P < 0.05);the good＿coverage index of group 1 and group 3was greater than that of the control group(P < 0.05).(2)At the 18 th day,the relative abundance of Firmicutes was greater in the group 1 and group 2 than in the group 3(P <0.05)at the phylum level.At the 35 th day,the relative abundance of Firmicutes was greater in the group 1 than in the control group(P < 0.05);the relative abundance of Proteobacteria was less in the group 2 than in the group 3(P < 0.05).From the 18 th day to the 35 th day,the relative abundance of Firmicutes was increased(P < 0.05),and the abundance of Bacteroidetes was decreased(P < 0.05)in the group 3;the relative abundance of Firmicutes had a tendency to increase.(3)At the genus level,at the 18 th day,the relative abundance of Lactobacillus was greater in the group 1 than in the other three groups(P <0.05).At the 35 th day,the relative abundance of Lactobacillus was greater in the group 1than in the control group and the group 3(P < 0.05);the relative abundance of Ruminococcaceae＿UCG-005 was greater in the group 2 than in the control group and the group 3(P < 0.05).From the 18 th day to the 35 th day,the relative abundance of Lactobacilluswas was reduced(P < 0.05),and the relative abundance of Ruminococcaceae＿UCG-005 was increased(P < 0.05)in the group 1;the relative abundance of Ruminococcaceae＿UCG-005 was increased(P < 0.05)in the group 2;the relative abundance of Lactobacillus was reduced(P < 0.05)in the control group.In summary,the acidifiers had certain effects on the blood indexes of piglets.So there was no adverse effects on the health and immunity of piglets.Acidifier 1 increased the ADG and ADFI of weaned piglets,and had the best growth-promoting effect on piglets.Acidifier 1 contains lactic acid,which improved the relative abundance of Lactobacillus in the intestine of piglets.It regulated the flora of the gastrointestinal tract and improved the growth performance of piglets.Acidifier 2 had a tendency to increase the survival rate of piglets,as well as a tendency to reduce the relative abundance of Proteobacteria in piglets.Acidifier 2 reduced pathogenic bacteria in the body and reduced the rate of diarrhea in piglets.Acidifier 2 and Acidifier 3 increased the level of T-AOC in the blood of piglets,improved their antioxidant and anti-stress ability,and reduced oxidation stress level.The acidifier 3 reduced the number of species in the feces microbes.Acidifier 1 and acidifier 3increased the relative abundance of Firmicutes.Acidifier 1 and acidifier 2 increased the relative abundance of Ruminococcaceae＿UCG-005,and had a certain effect on the degradation of carbohydrates.