Detection of Aeromonas Hydrophila in raw milk and some milk products with reference to its public health hazard

Abstract EN

This study aimed to determine Aeromonas spp.

in raw milk and some milk products.

A total of 100 raw milk, kareish cheese, ice cream and baladi yoghurt (25 samples, each) were collected from different dairy shops and street peddlers in Assiut city, Egypt and were bacteriologically examined for presence and count of Aeromonas spp.

The incidences of counted Aeromonas spp.

in raw milk, kareish cheese, ice cream and baladi yoghurt were 36, 32, 24 and 0.0%, respectively, with average counts of 1.0×105, 3.2×104, 5.0×102 and < 100 cfu/ml, respectively.

The incidences of counted Aeromonas hydrophila, in raw milk, kareish cheese and ice cream were 16, 12 and 8%, while for Aeromonas caviae, the incidences were 12, 16 and 12%, respectively.

Moreover, the incidences of counted Aeromonas sobria in raw milk, kareish cheese and ice cream were 8, 4 and 4%, respectively.

Baladi yoghurt samples were negative for Aeromonas spp.

in this study.

All the recovered Aeromonas hydrophila organisms were confirmed by PCR assay for the presence of 16S rRNA gene and 100% of the tested strains harboured this gene.

The aerA and ahh1 virulence genes were present in Aeromonas hydrophila in percentages of 66.67 and 77.78%, respectively.

All the recovered Aeromonas hydrophila, Aeromonas caviae and Aeromonas sobria strains, in this study, exhibited 100% virulence properties on bases of proteolytic, lioplytic, psychrotrophic and β-haemolytic activities.

The recovered Aeromonas hydrophila, Aeromonas caviae and Aeromonas sobria exhibited 100% resistance towards Ampicillin, Amoxicillin and Erythromycin antibiotics, while, they exhibited 100% sensitivity towards Ciprofloxacin.

The public health hazards of occurrence of Aeromonas spp.

in milk and its products as well as the suggestive control measures were discussed.