Phenotypic identification of Escherichia coli O157:H7 isolates from cattle at Suleja Abattoir, Nigeria

Abstract

Escherichia coli O157:H7 is a well-known pathogen of man and animals and a very low infection dose is needed to propagate the infection and clinical disease. In this study, a total of 515 rectal swab samples were collected from cattle and subjected to conventional biochemical tests. Presumptive identification on Eosine Methylene Blue (EMB) yielded an overall prevalence of 83.1%. Cefixime, Tallurite, Sorbitol MacConkey Agar (CT-SMAC) test yielded 18(4.2) isolates while Indole test, Methyl Red, Voges Proskauer and Citrate utilization test (IMVIC) biochemical test showed prevalence rate of 11(61.1%) and MicrogenTM test performed on the 18 Isolates yielded a prevalence rate of 33.3%. A total of 6 of the isolates were subjected to latex agglutination test, in which 2(0.4%) were confirmed to be E. coli O157. The results of the somatic flagella antigen test performed on the 2 isolates revealed that 1(50%) belonged to E. coli O157:H7. Thus this study is therefore the first research work to confirm the presence of E. coli O157:H7 in cattle presented for slaughter in Suleja abattoir in Nigeria. Humans can contract the infection through exposure, handling and consumption of beef or animal products. Control measures are therefore necessary especially during processing and evisceration of beef, to ensure safety of cattle offal presented to the public for human consumption. Key words: Escherichia coli O157:H7, cattle, Microgen kit, flagella staining, phenotypic identification, cattle, latex agglutination test.