Isolation, Identification and Antimicrobial Sensitivity Pattern of Bacteria Causing Egg Peritonitis in Layer Birds
Shanmugasundaram Udhayavel *
Department of Veterinary Microbiology, Veterinary College and Research Institute, Tamil Nadu Veterinary and Animal Sciences University, Salem, 636 112, India.
Tippichettypalayam Ramasamy Gopala Krishna Murthy
Poultry Disease Diagnosis and Surveillance Laboratory, Tamil Nadu Veterinary and Animal Sciences University, Namakkal-637 002, India.
Ayyasamy Elango
Veterinary College and Research Institute, Tamil Nadu Veterinary and Animal Sciences University, Salem, 636 112, India.
Arunagiri Senguttuvan Sobana
Department of Livestock Products Technology, Veterinary College and Research Institute, Tamil Nadu Veterinary and Animal Sciences University, Salem, 636 112, India.
*Author to whom correspondence should be addressed.
Abstract
Egg peritonitis is an important reproductive disorder of commercial layer chickens and is commonly associated with bacterial infection of the peritoneal cavity. The present study was conducted to isolate and identify bacterial agents associated with egg peritonitis in commercial layer birds and to determine their in vitro antimicrobial sensitivity pattern. Peritoneal swabs were collected from 50 commercial layer birds showing gross lesions suggestive of egg peritonitis during necropsy examination at the Poultry Disease Diagnosis and Surveillance Laboratory, Namakkal, Tamil Nadu, India, from May 2019 to March 2020. The affected birds belonged to different age groups ranging from 21 to 72 weeks and included Lohman, Bovans, Babcock and Hyline strains. Samples were processed using standard bacteriological methods. Isolates were identified based on cultural characteristics, staining reaction, morphology and biochemical tests. Antimicrobial susceptibility testing was performed by the disc diffusion method using selected antibacterial agents. Among the 50 samples examined, Escherichia coli was the most frequently isolated bacterium, accounting for 35 isolates (70%). Other bacteria isolated were Salmonella species in 4 samples (8%), Proteus species in 4 samples (8%), Klebsiella species in 3 samples (6%), Pseudomonas species in 3 samples (6%) and Gallibacterium species in 1 sample (2%). The highest overall sensitivity was observed to levofloxacin, with 32 isolates (64%) showing sensitivity, followed by ciprofloxacin with 30 isolates (60%). Sensitivity to co-trimoxazole, gentamicin, ampicillin, chlortetracycline and amoxicillin was 32%, 22%, 18%, 4% and 2%, respectively. No sensitivity was observed to neomycin, tylosin, lincomycin, bacitracin, colistin and erythromycin. The findings indicate that E. coli was the predominant bacterial agent associated with egg peritonitis in the examined layer birds, and fluoroquinolones showed comparatively higher in vitro activity against the isolates.
Keywords: Egg peritonitis, antibiogram, Escherichia coli, layer poultry