Control Of Salmonella In Broilers With Slightly Acidic Electrolyzed Water

Slightly acidic electrolyzed water（SAEW）is a kind of functional water with p H 5～6.5,which is rich in ROS,such as·OH,H₂O₂,HCl O and other components.SAEW has the advantages of broad-spectrum sterilization,safety and non-toxicity,green environmental protection,and convenient preparation,as well as is widely used in medical and health,food and agriculture.At present,studies have showed that SAEW can improve the production performance or immune performance of ewes,piglets and broilers,but there has few report on the prevention and treatment of Salmonella by SAEW in vivo.Since 2020,my country has banned the addition of antibiotic growth-promoting additives in feed,and a safe,non-toxic,green,and environmentally friendly alternative to antibiotics is urgently needed to prevent bacterial infection in animal.In this study,817 broilers were selected as experimental animals to evaluate the effects of SAEW on the production performance and immune performance of broilers and its anti-Salmonella infection effect,so as to provided an experimental basis for further application of SAEW in broiler production.In this study,self-made SAEW was used for high-throughput in vitro sterilization of 6pathogens including Escherichia coli,Salmonella,Staphylococcus aureus,Pseudomonas aeruginosa,Riemerella anatipestifer,and Clostridium perfringens.In the experiment,the sterilization effect was compared with two common chlorine-containing disinfectants calcium hypochlorite and 84 disinfectant.Based on the sterilization effect of SAEW in vitro,10 ppm,20 ppm,and 40 ppm of SAEW were used to feed broilers.The safety tesr was carried out with production performance such as weight gain and feed-to-weight ratio,immune performance（serum Ig G and Ig A）,liver and spleen organ index,and other indicators.A total of 120 1-day-old 817 broilers were randomly divided into 4 groups（n=10）,each group was repeated three replicates.The blank group completely drank tap water,the low concentration group completely drank 10 ppm SAEW,the medium concentration group completely drank 20 ppm SAEW,and the high concentration group completely drank 40 ppm SAEW for 28 days.According to the results of SAEW on broiler weight gain,serum and liver organ index and other indicators,the experiment of SAEW to control Salmonella in broilers was carried out,and the liver bacterial load and histopathological changes were used as the judging criteria.A total of 30 1-day-old 817 broilers were randomly divided into three groups（n=10）,including blank control group,positive group,and SAEW group.The blank group and the positive group drank tap water,and SAEW group drank SAEW.At the age of 3 days,the positive group and SAEW group were artificially orally infected with Salmonella Enteritidis 18044bacterial solution（400μL 10~5cfu/m L/piece）,and SAEW group drank 10 ppm SAEW 2 days before the challenge,and 40 ppm SAEW after the challenge electrolyte.On the 3rd day and the 7th day after the challenge,5 chickens were slaughtered and the indicators were detected.According to the previous experimental results,combined with production cost and other factors,10 ppm SAEW were selected for pilot test in Shandong Asia Pacific Zhonghui Group farm.80,000 1-day-old white-feathered broilers from the same batch were randomly divided into 2 groups（n=40,000）with two different batches of chickens.According to the normal production process,the control group drank drinking water in the field,and the experimental group drank 10 ppm SAEW except for the immunization link,and the test period was 39/40 d.The results of SAEW showed that 10 ppm of slightly acidic electrolyzed water was effective against 10~8 cfu/m L E.coli,Salmonella,S.aureus,P.aeruginosa,R.anatipestifer,and C.perfringens in vitro sterilization.Bacterial action for 5 minutes,the sterilization rate reached 99.999%;compared with calcium hypochlorite and 84 disinfectant,SAEW with lower concentration can achieve the same sterilization effect.The broilers who drank SAEW for 28 consecutive years,were in good spirits and had normal food and water intake.The results showed the weight gain and material-to-weight ratio of the electrolyzed water group were not significantly different（P>0.05）.There was no significant difference between blank group and electrolyzed water group in organ index with spleen（P>0.05）;tissue sections showed that the intestinal villi in the electrolyzed water group were normal,the mucosal epithelium was intact,the mucosal lamina propria was normal,and there were no obvious lesions.Compared with the blank group,the content of ALB in the low concentration group was significantly increased（P<0.05）,and the difference in the high concentration group was significantly increased（P<0.01）;the difference in the content of TP was not significant（P>0.05）;the difference in the content of ALT was not significant（P>0.05）;The content of AST in the high concentration group was significantly decreased（P<0.05）,and the difference between the low and medium concentration groups was not significant（P>0.05）;except that the content of CREA at 21 days in the middle concentration group was significantly increased（P<0.05）,the content of CREA and UA in the electrolyzed water group was not significantly different（P>0.05）.The serum Ig G and Ig A contents in the high concentration group were significantly decreased（P<0.05）,and the intestinal mucosal SIg A content was extremely significantly decreased（P<0.01）,and there was no significant difference between the low and medium concentration groups（P>0.05）.The richness and diversity of intestinal flora in the low-concentration group increased,and the relative abundance of beneficial bacteria such as Eisenberger,Lactobacillus and Lauterella in the low-and medium-concentration groups increased.The experimental results of the prevention and treatment of Salmonella in broilers with SAEW showed that the broilers in the positive group were lethargic and excreted loose feces,while the broilers in SAEW group were normal.Histological sections showed,the liver was obviously congested,hepatocyte degeneration and swelling,severe inflammatory reaction in the spleen,and cecal villi and mucosal epithelial shedding in the positive group;3days after challenge,the spleen and cecum of SAEW group were slightly inflamed,and the cecum was slightly congested,20%mild liver congestion and mild steatosis,and 80%had no obvious liver lesions in SAEW group;7 days after challenge,the spleen and cecum were no obvious lesions in SAEW group.Compared with the positive group,the bacterial load in the liver of SAEW group was significantly reduced;the SIg A of the cecal mucosa of SAEW group was significantly higher than that of the positive group（P<0.01）,but not significantly different from the blank group（P>0.05）.The results of the pilot test showed that the number of E.coli in the water line of the chicken house was reduced by 28%-52%,reaching the standard of safe drinking water;the weight of the experimental group was higher than that of the control group on 39/40 days,and the feed-to-weight ratio was reduced;the feed was changed at the age of 25 days.After 20 days,the fecal formation rate of the experimental group was higher than that of the control group;from the age of 20 days to slaughtering,the dead panning rate of the experimental group was 13%-18%lower than that of the blank group;the European index increased by 19-24.Laboratory research results showed that SAEW had broad-spectrum sterilization and fast sterilization,which is superior to traditional chlorine-containing disinfectants.10 ppm and 20ppm SAEW can promote the diversity of intestinal flora,etc.,40 ppm SAEW is used in combination.The control of Salmonella was effective for 7 days;the results of the pilot test showed that 10 ppm SAEW improved the production performance of white-feathered broilers.This study provides a reference for the application of SAEW in broiler breeding.