Bacterial microflora of normal and telangiectatic livers in cattle

Objective - To identify potential bacterial pathogens in normal and telangi ectatic livers of mature cattle at slaughter and to identify consumer risk associated with hepatic telangiectasia. Sample Population - 50 normal livers and 50 severely telangiectatic livers. Procedure - Normal and telangiectatic livers were collected at slaughter fo r aerobic and anaerobic bacterial culture. isolates were identified, and pa tterns of isolation were analyzed. Histologic examination of all livers was performed. Results - Human pathogens isolated from normal and telangiectatic livers in cluded Escherichia coli O157:H7 and group-D streptococci. Most livers in bo th groups contained bacteria in low numbers; however, more normal livers yi elded negative culture results, More group-D streptococci were isolated fro m the right lobes of telangiectatic livers than from the left lobes, and mo re gram-negative anaerobic bacteria were isolated from left lobes of telang iectatic livers than from right lobes. All telangiectatic lesions were free of fibrosis, active necrotizing processes, and inflammation. Conclusions and Clinical Relevance - The USDA regulation condemning telangi ectatic livers is justified insofar as these livers contain more bacteria t han normal livers do; however, normal livers contain similar species of mic roflora. Development of telangiectasia could not be linked to an infectious process. The finding of E coli O157:H7 in bovine livers suggests that info rmation regarding bacterial content of other offal and muscle may identify sources of this and other potential foodborne pathogens and assist in estab lishing critical control points for the meat industry.