Screening of Bacillus strains as potential probiotics and subsequent confirmation of the in vivo effectiveness of Bacillus subtilis MA139 in pigs

Abstract

A total of 124 samples were collected from the intestine of broiler chickens, piglet faeces, fermented foods, soils and Chinese herbs. More than 750 strains of aerobic, spore-forming bacteria were isolated from these samples. The inhibitory activity of these spore-forming strains against Escherichia coli K88, E. coli K99, Salmonella typhimurium and Staphylococcus aureus was assessed using a disc plate diffusion assay. The six bacilli with the largest inhibition zones against the four indicator bacteria were chosen and assessed for their resistance to unfavorable conditions within simulated gut environments. The strain Bacillus subtilis MA139 showed full resistance to pH 2, 0.3% bile salts and exhibited the highest antimicrobial activity. Based on these results, B. subtilis MA139 was selected as a potential probiotic and fed to piglets at concentrations of 2.2 x 10(5), 2.2 x 10(6) or 2.2 x 10(7) CFU/g of feed during a 28-day feeding trial. A negative control consisting of the basal diet with no additives and a positive control consisting of the basal diet supplemented with 16 g/ton flavomycin were also included. Ninety piglets between 35 and 40 days old were used in the in vivo animal trials. B. subtilis MA139 enhanced daily gain (P = 0.10) and feed conversion (P = 0.03) compared with the negative control. The performance of pigs fed B. subtilis MA139 supplemented diets did not differ from that of pigs fed the antibiotic diet. There was a significant increase in Lactobacilli cell counts (P = 0.02) and a numerical decrease in E. coli counts (P = 0.05) in the faecal samples of pigs fed B. subtilis MA139 with 2.2 x 10(5) CFU/g of feed. The overall results of this study show that the use of initial co-culture with indicator pathogens, a disc plate diffusion assay and simulated gut environment tolerance tests is one of effective methods of screening Bacillus for probiotic use and that B. subtilis MA139 is a promising alternative to antibiotics for use as a feed additive in piglet diets.

Antibiosis and dark-pigments secretion by the phytopathogenic and environmental fungal species after interaction in vitro with a Bacillus subtilis isolate

“…The genus Bacillus is widely diversified and spread throughout the world from many sources such as air, soil, water, and gastrointestinal tracts of animals and humans (Guo et al, 2006, Earl et al, 2007, Rintala et al, 2008. Many species are extremophyles, or tolerant to more strict conditions such as high alkalinity, acidity, salinity or temperature (Niehaus et al, 1999, Horikoshi, 2008.…”

Desempenho de bezerros leiteiros recebendo probiótico contendo Bacillus subtilis e Bacillus licheniformis

“…Os probióticos são definidos como aditivos alimentares de microrganismos vivos os quais os benefícios afetam o animal hospedeiro melhorando o equilíbrio da microbiota intestinal (FULLER et al,1989). Segundo Vanbelle et al (1990), após uma dosagem oral efetiva, são capazes de estabelecer-se no trato gastrintestinal e manter ou aumentar a microbiota natural, ajudando a prevenir a colonização por microrganismos patogênicos, assegurando melhor utilização dos nutrientes (HOLZAPFEL et al, 2001;SCHAREK et al, 2005;GUO et al, 2006). Há inúmeros trabalhos verificando a utilização de probióticos em bezerros, pois as primeiras semanas de vida são muito importantes para seu desenvolvimento e produção futuros.…”

Bacillus species are Superior Probiotic Feed-Additives for Poultry

“…25 Several studies have showed that Bacillus spores can be found in the intestinal tracts of animals where they live and multiply actively, raising the question of whether this could be where they live and grow. [25][26][27][28][29][30] For instance, has been reported that soil carries approximately 10 6 spores/g of soil while human feces present an average of up to 10 4 spores/g. The numbers of spores found in human feces, is too high to be accounted for principally by ingestion of food contaminated with spores from soil.…”

“…is commensal bacteria of the GI-track. 26,27,31,32 Other major advantages of spores over vegetative (LAB) cells are their thermostability to high temperatures spores can survive at 235°F (113°C) for 8minutes. 28,33,34 This thermostability property allow incorporate the spores into the feed the during the milling and pelletizing of the feed and other applications as production of vaccines incorporate as adjuvants.…”

“…In addition, spores are resistant to desiccation and other stress factors like bile and low pHs both present in the gastric juice. 26,27,32 Bacillus spores have different mode of action in the GItrack per se are able to adsorb toxins, induce the innate immunological response through interaction with the Toll-like receptors of the host cells (TLR2 and TLR4), 37 stimulating of NF-bk pathway increasing the levels of NK cells, induction of cytokines (IFN-g), 38,39 improve intestinal integrity and stabilize the microflora, enhance the Daily weight gain (DWG) of the chickens and the Feed Conversion Ratio (FCR). 26,40 Other important characteristic of Bacillus ssp.…”