Abstract of research

INCIDENCE OF LISTERIA MONOCYTOGENES IN FRESH TILAPIA NILOTICA FISH

Edris, A.M, Amany M.S and Michael A. Fouad

Abstract

In the present study one hundred random samples of fresh Tilapia nilotica samples were purchased from different fish markets in Cairo, Kalyobia and Beheira governorates. The collected samples were bacteriologically examined for detection of L. monocytogenes. The obtained results revealed that 7 of L. monocytogenes were isolated from fresh Tilapia nilotica fish samples in Egyptian fish market identified by biochemical test. The 7 isolates were exposed to PCR technique and only 4 isolates were confirmed to be L. monocytogenes. The highest prevalence of Listeria monocytogenes (3%) was observed in fresh Tilapia nilotica from marketed fish while lower prevalence of L. monocytogenes (1%) was seen in fresh Tilapia nilotica from farm fish. Concerning the other Listeria species, 27 isolates, eight isolates (8%) were L. ivanovii, five isolates (5%) were L. innocua, five isolates (5%) were L. seeligeri, six (6%) isolates were L. welshimeri, and three (3%) isolates were L. grayi. The public health significance of the isolated microorganisms and the probable sources of Tilapia nilotica contamination as well as the suspected recommendations to prevent them to gain access to such food items were discussed.