الفهرس 
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Abstract
This study was undertaken to determine the prevalence of Pseudomonas species in bulk milk tanks, Talaga cheese, cream, and butter. Pseudomonas spp. were isolated and counted using Pseudomonas agar base media supplemented with CFC supplement. The proteolytic and lipolytic activity of isolated Pseudomonas species were determined besides molecular identification of virulence genes using PCR. In addition, the antimicrobial resistance pattern was determined. A total of 150 milk and dairy product samples were collected (30 markets raw milk, 20 farm bulk milk tanks, 35 Talaga cheese, 10 pasteurized milk, 10 pasteurized cream, 20 raw cream, and 25 butter) from different supermarkets, dairy shops, and dairy farms in Dakahlia Governorate, Egypt. The total prevalence of Pseudomonas species was 44.66% (67/150) in all examined samples. The prevalence was in raw cream 70%, market raw milk 66.66%, bulk milk tanks 50%, Talaga cheese 48.57%, pasteurized cream 20%, butter 16% and pasteurized milk 0%. The isolated Pseudomonas species were P. aeruginosa 38.5%, P. fluorescence 37.3%, P. fragi 10.8%, P. psychrophile 6%, P. proteolytica 2.4%, P. alcaligens 2.4%, P. lundensis 1.2% and P. brenneri 1.2%. The Pseudomonas species proteolytic activity was 79.5% (66/83) and the lipolytic activity was 48.2% (40/83) with the highest proteolytic and lipolytic activity detected in P. aeruginosa and P. fluorescence. Fourteen antibiotics were selected to detect the AMR in only 59 isolates of Pseudomonas species. The higher antimicrobial resistance was against Ampicillin (100%) followed by Colistin (98%), while the antibiotic sensitivity was higher against Imipenem (96.6%), then Meropenem (91.5%). Ten isolates of antimicrobial resistance Pseudomonas aeruginosa were serotyped and classified into various serotypes (O2, O4, O5, O8, and O11) and groups (B, C, E, and F). Molecular identification of virulence genes of P. aeruginosa, P. fluorescens, and P. fragi was detected using the multiplex PCR method. The incidence of LasB, ExoS, and pilB as virulence factors in ten isolates of antimicrobial resistance P. aeruginosa were 10 (100%), 8 (80%), and 4 (40%), respectively. While the incidence of aprX as a virulent gene of P. fluorescens was found in the four examined isolates of P. fluorescens, and the carA gene was found in the two examined isolates of Pseudomonas fragi. The public health and economic impact of Pseudomonas species in milk and dairy products were also reviewed.