No abstract

Paratyphoid Salmonella has emerged as a global problem for humans and poultry. Therefore, in this study we investigated the occurrence, serological, antimicrobial and molecular characteristics of paratyphoid Salmonella isolated from chicken flocks at Sharkia Governorate during 2015-2016. The prevalence of paratyphoid Salmonella among the 150 suspected flocks was 32.6 % (49/150), the highest rate (41/49; 80%) was among young ages (1-10 days old) and the lowest rate (8/49; 16 %) among older ages (11-21 days old). The highest recovery was from liver (30.66 %), followed by spleen (25.33 %), caecum (20 %) and yolk sac (15.7 %). Serotyping of 49 Salmonella isolates revealed 11 different serogroups, with Salmonella Typhimurium was the most prevalent one (24.49 %), followed by Salmonella Kentucky (18.36 %) and Salmonella Enteritidis (14.28 %). The most sensitive antibiotics were apramycin (82 %) and ciprofloxacin (65 %). Multidrug resistance (MDR) was significant to ampicillin, gentamycin and cefotriaxone in all Salmonella isolates. All phenotypically identified MDR Salmonella were found to possess invA, hilA, pefA (100%) and avrA (95 %) genes by polymerase chain reaction (PCR), confirming that these virulence genes are important virulence markers for rapid diagnosis of Salmonella infection.