Saadia Aziz

Saadia Aziz

University of New Hampshire



Mentor: Dr. Frank Rodgers, Department of Microbiology

Lactobacillus reuteri as a Probiotic Treatment to Control Escherichia coli O157:H7 in Cattle Bedding

Escherichia coli O157:H7 is an important human pathogen, which can cause hemorrhagic (HC) and hemolytic-uremic syndrome (HUS) (Weagant, et al., 1994). Cattle, as well as other animals, have been noted as principal reservoirs of E. coli O157:H7. Cattle harboring this pathogen play a major role in food-borne outbreaks, and in particular in outbreaks associated with undercooked meat (Paton and Paton, 1998). According to Ohya, Marbushi and Ito (2000), feedlot cattle can shed E. coli O157:H7 in their feces, which can lead to infection as well as reinfection of others. Methods for reducing or eliminating the prevalence of E. coli O157:H7 in cattle are urgently needed to diminish the level of pathogen contamination in food and in the environment.

Probiotic bacteria are those that beneficially affect the host by improving microbial balance, including the reduction or elimination of microorganisms that may prove harmful to humans. The term probiotic is generic and is a term used to encompass all microbial cultures, extracts and enzyme preparations that have a health benefiting impact (Reid et al., 1999; Salminen et al., 1996; Sobel, 1999). Lactobacilli have the ability to colonize a variety of animals, and thus inhibit the growth of different, pathogenic microorganisms through the production of lactic acid (Ohya, et al., 2000).

Cattle bedding, made of components such as wood chips, straw, compost, rubber, etc. have been noted as pre-disposing factors for outbreaks of mastitis due to pathogens such as E. coli (Schukken et al., 1989).In order to control the prevalence of E. coli O157:H7 amongst cattle, a multi-strategy approach must be established. The aim of my potential research is to create just another approach to reduce E. coli O157:H7 by using a spray of lactobacilli as a probiotic treatment to out compete and thereby reduce E. coli O157:H7 in cattle bedding.

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