Screening Of Lactic Acid Bacteria Isolated From Piglet And Its Effect On Piglets

The study was conducted to isolate and screen the excellent homologous lactobacillus strains,which were made of active highly mixed lactobacillus applicated on piglets.30-strains Laetobaeillus were isolated, and4strains were filed out through the vitro screening. Identification of the4strains of bacteria were Enterococcus faecium,Enterococcus gallinarum,Lacidlophilus acidophilus,L.oris,which were mixed culture,the low cost and high actively medium was designed and screened by MRS. Finally, four strains were made of solid mixed bacterias used in piglets and antibiotics was used as control, provided theoretical basis for the application of lactic acid bacteria in piglets.1. The Isolation screening and identification of bacteriaSemi-selective MRS plates was adjusted to pH=5.0,30strains Laetobaeillus,Gram staining masccline and non-spore, were isolated from excreta of28days healthy piglets,and numbered R1、 R12、...R29、R30.Application of in vitro treatment by acid, bile tolerance, antimicrobial inhibition, acid production, at pH=2for2hours,there are13stains survival rates morn than30%,7strains of survival rates morn than10%after in the bile salt concentration of0.3%.4strains,R11、R15、R18、 R22, which have strong inhibition on both Pathogenic EScherichia coli and Salmonella, The4bacteria by antimicrobial inhibition and acid production test, the diameter of inhibition zone was bigger than18mm and pH<4.0.Through the microscopy(10×100), R11, R15were coccus, R18, R22were bacillus in initially observation. R11, R15belong to the Enterococcus,R18、R22were ideniified as the members of the genus Lactobacillus,according to the characteristics of colony morphology,Catalase test,nitrate reduction test,gelatin liquefaction test,inlole test,hysrogen sulfide test,the growth test in pH9.2and pH9.6,4%and16.5%NaCl growth test,carbohydrate fermentation test,mobility test; R11,R15,R18,R22respectively was E.faecium,E gallinarum, Lactobacillus acidophilus,L.oris,through the Arg test,V-P test and carbohydrate the Carbohydrate fermentation test. 2The mix of the bacteriaof bacteria count adjusted to the same concentration,the same volume of bacteria were10%inoculated, Four strains were singled and mixed culture,the OD of strains was determinated.After mixed culture of4strains by checking, colony characteristics, microscopic examination, part of the qualification test showed that the4strains were survivaled,the viable strains (CFU/mL) were R11> R22> R18> R15.The growth curve result showed that mixed culture OD was higher than any one single culture strains, indicated that4strains mixed culture better than cultured alone, so complex strains were more valued. Mixed bacteria liquid with carrier (wheat bran and soybean crush1:1) by1:1(Kg/Kg).drought treatment、anti-caking、sealing,dehydration low temperature preservation3Designation and selection of manufature mediumsThe designation of four mediums, soybean meal, corn flour as the main ingredient.The result showed that the medium II was significantly effect,Bacteria number can reach10111012CFU/mL,as well as the viable strains in the medium II was significantly higher than the medium Ⅰ,Ⅲ,Ⅳ(P<0.05),pH can be reduced to3.49.The pH was significantly difference (P <0.05) comparewd with single cuture in this medium.4The application of lactobacillus in lactation and weaning piglets0.2%Lactobacillus were added into the basal diet of lactation and weaning piglets.control with antibiotics group. weight, litter size, parity, date of birth similar to the purebred Landrace pigs6nest.which were randomly assigned to2dietary treatments with3replicates,and each replicate contained10piglets.The piglets were fed the basal diet with antibiotics and lacidlophilus respectively,There were no significant differences between two groups in the average daily feed intake (ADFI),average daily gain (ADG),the total feed intake of per piglet,the ratio of feed to gain (F/G),diarrhea and mortality rates (P>0.05)...