Bacteriology of chicken meat samples from Bharatpur, Chitwan, Nepal

Many food-borne diseases are associated with the consumption of chicken meat and thus are of public health significance worldwide. A cross-sectional study was done to isolate, identify, and characterize bacteria from chicken meat samples of Bharatpur, Chitwan. A total of 102 samples were randomly collected and processed at the Microbiology laboratory of Birendra Multiple Campus, Chitwan for three months (May-July 2016). One gram of each sample was crushed on 9 ml distilled water in a sterile mortar pestle followed by serial dilution and inoculation of 0.1 ml sample into suitable culture media and incubated at 37 оC for 24 hours. Identification of the isolates was done by microscopic examination and biochemical tests and the antimicrobial susceptibility pattern of the isolates was determined by the Kirby Bauer disc diffusion method. Out of 102 meat samples, the growth positivity rate was 94.0% (n = 96/102) on all of the culture media. 26/48 fresh and 44/54 frozen samples gave positive growth with 36 isolates from fresh and 60 isolates from frozen meat samples, with the occurrence of Staphylococcus aureus 26(27.08%), Pseudomonas spp 6(6.25%), Proteus spp 4(4.16%), Escherichia coli 22(22.91%), Salmonella spp 16(16.66%), Citrobacter spp 8(8.33), Acinetobacter spp 8(8.33%), Streptococcus spp 2(2.08%), Shigella spp 4(4.16%) and Vibrio spp 2(2.08%). Cefalexin (92.85%) was the most effective antibiotic against Gram-positive bacteria followed by Amoxicillin (71.42%) and Methicillin (64.28%). The least effective antibiotic was Ampicillin (50%). Similarly, Gentamicin (76.47%) followed by Nalidixic acid (41.47%) were effective against Gram-negative bacteria, while some showed resistance to all three classes of drugs exhibiting MDR.