African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5233

Full Length Research Paper

Evaluation of protective effect of probiotic in sheep against experimental infection by Escherichia coli

Everlon Cid Rigobelo1*, Renato Pariz Maluta2, Clarissa Araújo Borges2, Lívia Gerbasi Beraldo2, Marita Vedovelli Cardozo2, Sirlei Aparecida Maestá1, Manoel Victor Franco Lemos3, Urbano dos Santos Ruiz1, and Fernando Antonio de Ávila4
1Experimental Campus of Dracena UNESP, Univi Estadual Paulista; Brazil.  2Post- Graduate Program of Microbiology, FCAVJ, Univi Estadual Paulista; Brazil. 3Department of Applied Biology, FCAVJ, Univi Estadual Paulista; Brazil. 4Department of Veterinary Pathology, FCAVJ, Univi Estadual Paulista, Brazil.
Email: [email protected]

  •  Accepted: 15 March 2013
  •  Published: 02 April 2013


Domestic ruminants, especially sheep and cattle, are the main reservoirs of Shiga toxin-producing Escherichia coli (STEC) and may transmit this pathogen to human. Probiotics are "live organisms that, when administered in adequate amounts, confer a health benefit on the host", decreasing the infection and its dissemination. However, these benefits are conferred only after the colonization of probiotic strains in the gut of the animal, which may be impaired by normal microbiota. The aims of this study were to determine whether the inoculation of sheep with probiotic strains decreases the shedding of STEC and to determine whether the age of sheep interferes with this protective effect. Sheep that received oral inoculums at a concentration of 2 × 109 cells per mL of viable STEC bacteria, which are carriers of stx1, stx2 and eae genes, were compared with other sheep that did not receive inoculums. When probiotic bacteria were inoculated together with the STEC, the number of pathogenic bacteria in the population was similar to the control. The protective effect of probiotic strains was largest in groups with younger animals than with older animals. These findings suggest that the use of probiotic strains in sheep may decrease the intestinal shedding by STEC as well as the fact that the age of the sheep may interfere in the protective effect of probiotics against colonization by STEC.


Key words: Probiotic, protective effect, Escherichia coli, sheep.