CHARACTERIZATION AND SELECTION OF PROBIOTIC LACTOBACILLI FOR A PRELIMINARY MINIPIG FEEDING TRIAL AND THEIR EFFECT ON SERUM-CHOLESTEROL LEVELS, FECES PH AND FECES MOISTURE-CONTENT

Three out of 297 lactobacillus strains isolated from pig faeces were s elected for a feeding trial on account of their high bile-salt hydrola se (BSH) activity, bile-salt resistance, low pH tolerance and the prod uction of antimicrobial substances. Two strains were identified as Lac tobacillus johnsonii and one as Lactobacillus reuteri by DNA-DNA hybri disation. L. johnsoniii BFE 1061 produced a bacteriocin active against a range of lactic acid bacteria (LAB) and nonrelated bacteria includi ng Clostridium perfringens. Six minipigs were maintained on a high-fat , high-cholesterol ('Western Style') diet for 17 weeks after which the diet was supplemented with the 'probiotic mixture' containing the abo ve mentioned three Lactobacillus strains at 2 x 10(12) CFU per pig per day for five weeks. The mixture was given as a resuspended lyophilisa te. During a two week follow-up period the minipigs received only the 'Western-style' diet without probiotic supplementation. A lowering eff ect on serum cholesterol levels was indicated after three weeks probio tic feeding, concomitant with an increase in the moisture content of t he faeces and Lactobacillus cell numbers. Triglycerides, pH and number of lactic acid bacteria in faeces were not significantly influenced b y probiotic supplementation. (C) 1998 Elsevier Science B.V.