Study On The Difference Of Intestinal Microlfora Between Healthy And Diarrheal Piglets And Screening Of Porcine Lactobacillus

Piglet diarrhea is a digestive disorder syndrome, piglet diarrhea will lead to secondaryinfection and will decrease immunity and increase mortality of piglet, so it seriously doharm to the pig raising industry. In this study, healthy and diarrheal piglets’ feces wereused as research objects, the total number of bacteria, bifidobacteria, lactobacillus,enterococci and E.coli were counted by the traditional culture method; The diversity ofintestinal microflora and lactobacillus were studied by the method of PCR-DGGE. Havingisolated several strains of lactobacillus from healthy piglet’s fresh feces, And screening testof acid-resistance，bile salts-resistance, the ability of producing lactic acid, the inhibition ofE.coli and salmonella were did.1.Compared to healthy piglets, the number of total bacteria, bifidobacteria,lactobacillus decreased, and the difference was very significant in total bacteria at21days,the difference was significant in lactobacillus at21days and bifidobacteria at7and21days.The number of E.coli in diarrheal piglets increased compared to healthy piglets, but notsignificant. The number of enterococci in diarrheal piglets increased compared to healthypiglets at7days, at other days, the number of enterococci decreased, but the differenceswere all not significant.2．The complex of intestinal microflora was related to severity of dysbacteriosis andthe days of piglets. DGGE fingerprint gradually became complicated with the increase ofdays in healthy piglets. Cluster analysis basicly showed two families which splited atweaning. Compared to healthy piglets’ DGGE fingerprint, diarrheal piglets’s had less lanes,suggested that the dominant microflora had decreased.3．Compared to healthy piglets, there was a decrease in the number of total bacteriaand lactobacillus at21days in pigfarm A. And the difference was significant. The clusteranalysis of DGGE fingerprint showed that there were lowest similarity on total bacteria andlactobacillus between healthy and diarrheal piglets at the same days.This suggested thatmaybe there was a certain correlation at the change of bacteria structure and bacterianumber when piglets diarrhea.4．Having isolated and screened two strains of lactobacillus salivarius and one strainof lactobacillus plantarum from healthy piglets’ feces which can resist acid, bile salt andhave good characteristics.