Bacterial pathogens associated with cellulitis in chickens

Cellulitis is a serious problem for the poultry industry because of increased condemnations, carcass downgrading at processing, and higher labor costs to process affected flocks. In the present study, the prevalence of cellulitis was studied in 240 broiler chickens. The correlation between cellulitis and other systemic lesions of the same bird was investigated also. Moreover, identification of the causative bacterial agents was conducted focusing on E. coli and Salmonella isolates. The prevalence rate of cellulitis in examined broiler chickens was 38.3%. Cellulitis without systemic lesion was observed in 14.2% of birds while 24.2% of birds had cellulitis associated with other systemic lesions in the internal organs while hepatitis was the most frequent. The bacteriological examination revealed that of 253 samples collected, a total of 157 bacterial isolates were recovered (62.1%). Among the recovered isolates, E. coli was the most prevalent (126 isolates; 80.3%) as well as 4 Salmonella species (2.5%), 9 Proteus species (5.7%), 7 Pseudomonas aeruginosa (4.5%), 3 Enterobacter species (1.9%) and 8 Staphylococcus aureus (5.1%). Serogrouping of E. coli isolates revealed that O125 was the most prevalent; 32%, followed by serogroups O158, O55, O78 as 24%, 12%, 10%, respectively, then both O1 and O8; 6% for each, and finally O15; 4%. Antibiogram of E. coli isolates showed a high sensitivity against enrofloxacin only (81%) while they were moderately sensitive to apramycin (65.9%) and colistin sulphate (61.9%) as well as ciprofloxacin and cefotaxime sodium (56.3% and 55.6%, respectively). On the other hand, high moderate degrees of resistances were observed against the other antimicrobials. Salmonella isolates showed complete sensitivities to ciprofloxacin and enrofloxacin while they were completely resistant to most of antimicrbials.