Isolation of listeria monocytogenes from farm bulk milk cans

One hundred raw milk samples collected from bulk milk cans belonged to 15 dairy farms at Giza Governorate. They represented 10 buffalo farms and 5 cow farms. They were examined bacteriologically for the detection and isolation of Listeria monocytogenes. All samples from buffalo milk [65 samples] were negative while, 8 out of 35 cow milk samples were positive for the presence of Listeria monocytogenes. All isolated strains were pathogenic to mice and killed them within 4 days following inoculation