Potential influence of dairy propionibacteria on the growth and acid metabolism of Streptococcus bovis and Megasphaera elsdenii

Abstract

Ruminal acidosis is a prevalent disorder among dairy cows and feedlot cattle, which can significantly impair their health and productivity. This study, involving seven different strains of dairy propionibacteria, represents an in vitro investigation of the feasibility of using these organisms as direct-fed microbials to control lactic acid acumulation in the rumen. Interactions between the propionibacteria, Streptococcus bovis and Megasphaera elsdenii were evaluated in terms of effects on lactic, acetic and propionic acid metabolism, following co-incubation. Spot resistance tests showed slight but varying degrees of growth inhibition by S. bovis among the propionibacteria, while no inhibition was observed between M. elsdenii and the different strains of dairy propionibacteria. In the co-culture experiments comprising S. bovis in nutrient broth, significant differences in pH and the levels of production of lactic, acetic and propionic acid, were observed between treatments following inoculation with various propionibacteria and/or M. elsdenii. In general, lactic acid concentrations at the end of the incubation were significantly lower in the cultures containing propionibacteria compared with cultures comprising either S. bovis only or S. bovis + M. elsdenii, although efficacy of lactate metabolism varied between species and strains. Moreover,the accumulation of acetic and propionic acid in the combined cultures, but not in the solo S. bovis culture, indicated that these compounds were produced as a result of the metabolism of lactic acid by the propionibacteria and M. elsdenii.

Anaerobic flora, Selenomonas ruminis sp. nov., and the bacteriocinogenic Ligilactobacillus salivarius strain MP3 from crossbred-lactating goats

“…The protocol followed the method of Luo, et al 60 . The 24 h inoculum of bacterial strains in MRS broth was used in this test.…”

The in vitro Effect of Fibers With Different Degrees of Polymerization on Human Gut Bacteria

“…Prevotella, a commensal bacterium, improves the ability of intestinal bacteria to degrade complex polysaccharides and fibers (Petia et al, 2015). Bacteroides, a butyric acid producer (Louis et al, 2004;Shin et al, 2017), Lactobacillus, predominantly a lactic acid producer, and Megasphaera, a lactic acid and SCFA producer (Luo et al, 2017), induced an acidic environment, thereby decreasing the abundance of Escherichia-Shigella (Meng et al, 2017). The pH was close to neutral in the CMC-treated fermentation, which provided Escherichia-Shigella with a suitable growth environment.…”

Dairy Propionibacteria: Versatile Probiotics

“…The presence of P. acidipropionici also limited the growth of Bacteroidetes fragilis and Clostridium hystoliticum groups in mice cecal slurries with and without fiber supplementation [61]. In addition, several strains of dairy propionibacteria were able to inhibit in vitro Steptococcus bovis in ruminal acidosis context [62]. …”