Use of probiotics to reduce faecal shedding of Shiga toxin-producing Escherichia coli in sheep

Abstract

Shiga toxin-producing Escherichia coli (STEC) are zoonotic, foodborne pathogens of humans. Ruminants, including sheep, are the primary reservoirs of STEC and there is a need to develop intervention strategies to reduce the entry of STEC into the food chain. The initiation of the majority of bacterial, enteric infections involves colonisation of the gut mucosal surface by the pathogen. However, probiotic bacteria can serve to decrease the severity of infection via a number of mechanisms including competition for receptors and nutrients, and/or the synthesis of organic acids and bacteriocins that create an environment unfavourable for pathogen development. The aim of the current study was to determine whether the administration of a probiotic mixture to sheep experimentally infected with a non-O157 STEC strain, carrying stx1, stx2 and eae genes, was able to decrease faecal shedding of the pathogen. The probiotic mixture contained Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus bulgaricus, Lactobacillus lactis, Streptococcus thermophilus and Enterococcus faecium. The numbers of non-O157 STEC in faecal samples collected from sheep receiving daily doses of the probiotic mixture were significantly lower at the 3rd, 5th and 6th week post-inoculation when compared to the levels recorded in untreated animals. It was concluded that administration of the probiotic mixture reduced faecal shedding of non-O157 STEC in sheep, and holds potential as a pre-harvest intervention method to reduce transmission to humans.

Presence of pathogenic Escherichia coli is correlated with bacterial community diversity and composition on pre-harvest cattle hides

“…Additionally, sheep fed a cocktail of probiotic bacteria including several Lactobacillus spp. , Streptococcus thermophilus and Enterococcus faecium showed a reduction in non-O157 STEC fecal shedding [ 62 ]. Thus, Streptococcus may be a useful bacterium in the prevention of STEC colonization in the gut and on the hide.…”

Milk Microbiota: What Are We Exactly Talking About?

“…The study had the advantage of examining two different breeds kept in the same farm and under the same environmental conditions and diets. As a result, Rendena cows showed a lower biodiversity in their milk microbiota than did Holstein and a higher prevalence of Streptococcus thermophilus, a thermophilic lactic acid bacterium with a prominent role in dairy product fermentation (Quigley et al, 2013) and with a potential role in protection against mammary pathogens (Nader-Macias et al, 2008;Espeche et al, 2012;Rigobelo et al, 2015). Further characterization of the microbiota composition of 117 healthy quarter milk samples of the two breeds during their periparturient period showed a significantly lower bacterial biodiversity and a more stable microbiota in Rendena milk, while Holstein milk displayed more significant changes in their milk bacterial composition (Cremonesi et al, 2018).…”

Antibiotic‐resistant Shiga toxin‐producing Escherichia coli: An overview of prevalence and intervention strategies

“…The inoculation of animals with a probiotic prior to an experimental STEC infection has demonstrated preventative capabilities (Reissbrodt et al, ). Probiotic mixtures containing bacteria Lactobacillus acidophilus, L. helveticus, L. bulgaricus, L. lactis , Streptococcus thermophilus and Enterococcus faecium have been shown to effectively reduce STEC shedding in sheep (Rigobelo, Karapetkov, Maesta, Avila, & McIntosh, ). These lactic acid bacteria have also been reported to reduce faecal shedding of O157 in cattle (Brashears, Jaroni, & Trimble, ).…”

“…Probiotic preparations contain microorganisms that are beneficial to the host and have a preventative activity against STEC infections (reviewed in Rahal, Fadlallah, Nassar, Kazzi, & Matar, 2015). The inoculation of animals with a probiotic prior to an experimental STEC infection has demonstrated preventative capabilities (Reissbrodt et al, 2009 (Rigobelo, Karapetkov, Maesta, Avila, & McIntosh, 2015). These lactic acid bacteria have also been reported to reduce faecal shedding of O157 in cattle (Brashears, Jaroni, & Trimble, 2003).…”