The effect of yoghurt on the growth, lactose-utilizing gut organisms and β-glucuronidase activity of caecal contents of a lactose-fed, lactase-deficient animal

Effects of a Lactobacillus salivarius mixture on performance, intestinal health and serum lipids of broiler chickens

The ban or severe restriction on the use of antibiotics in poultry feeds to promote growth has led to considerable interest to find alternative approaches. Probiotics have been considered as such alternatives. In the present study, the effects of a Lactobacillus mixture composed from three previously isolated Lactobacillus salivarius strains (CI1, CI2 and CI3) from chicken intestines on performance, intestinal health status and serum lipids of broiler chickens has been evaluated. Supplementation of the mixture at a concentration of 0.5 or 1 g kg-1 of diet to broilers for 42 days improved body weight, body weight gain and FCR, reduced total cholesterol, LDL-cholesterol and triglycerides, increased populations of beneficial bacteria such as lactobacilli and bifidobacteria, decreased harmful bacteria such as E. coli and total aerobes, reduced harmful cecal bacterial enzymes such as β-glucosidase and β-glucuronidase, and improved intestinal histomorphology of broilers. Because of its remarkable efficacy on broiler chickens, the L. salivarius mixture could be considered as a good potential probiotic for chickens, and its benefits should be further evaluated on a commercial scale.

Digestive and bacterial enzyme activities in broilers fed diets supplemented with Lactobacillus cultures

A study was carried out to investigate the effects of adherent Lactobacillus cultures on 1) amylolytic, lipolytic, and proteolytic enzyme activities in the contents of the small intestine (from the distal end of the duodenum to the ileocecal junction) and 2) bacterial beta-glucuronidase and beta-glucosidase activities in the intestinal contents and feces of broiler chickens. Three dietary treatments were randomly assigned to three groups of chicks, i.e., basal diet only (control group), basal diet + 0.1% dried culture of Lactobacillus acidophilus, and basal diet + 0.1% dried culture of a mixture of 12 Lactobacillus strains. The results showed that supplementation of the adherent Lactobacillus cultures to chickens, either as a single strain of L. acidophilus or as a mixture of 12 Lactobacillus strains, increased significantly (P < 0.05) the levels of amylase in the small intestine. However, the proteolytic and lipolytic activities in the small intestine were not affected by addition of either of the adherent Lactobacillus cultures. Addition of either L. acidophilus or a mixture of 12 Lactobacillus strains was also found to reduce significantly (P < 0.05) the intestinal and fecal beta-glucuronidase and fecal beta-glucosidase but not the intestinal beta-glucosidase at 40 d of feeding.

A note on lactobacilli and beta-glucuronidase activity in the intestinal contents of mice

A comparison was made of caecal beta-glucuronidase activity in the caecal contents of mice with or without lactobacilli as members of the normal microflora. Male mice that did not have lactobacilli as intestinal inhabitants had approximately 52% more caecal beta-glucuronidase activity than their female counterparts. Colonization of male mice by lactobacilli reduced the beta-glucuronidase activity to that of female mice.