Abstract:
The present study was carried out to isolate, identify and to know antibiogram profiling of
Escherichia coli and Salmonella spp. from the supplied drinking water in different cattle
farms in Dhaka city within the period of October, 2020 to April, 2021. A total of 100
fresh water samples were randomly collected from different cattle farms and transported
to the Microbiology and Parasitology laboratory of Sher-e-Bangla Agricultural University
for microbiological analysis. Primary culture was done in nutrient broth and nutrient agar.
Pure culture was obtained from different selective media. Bacteria were identified by
observing the growth properties in different media, staining properties and biochemical
tests. The characteristics of E. coli colonies were red to bright pink colored in
MacConkey agar and greenish red colored with faint metallic sheen in EMB (Eosin
Methylene Blue) agar. The characteristics of Salmonella spp. colonies were black colored
in SS agar and pink colored in MacConkey agar. In Gram’s staining, E. coli revealed
gram-negative, pink color, small rod-shaped appearance, arranged in single or paired
short, and Salmonella spp. revealed gram negative, short rod shaped, singly arranged. The
occurrence of E. coli was 46% and Salmonella spp. was 37%. Pure isolates were
subjected to antibiogram by disc diffusion method against 5 different antibiotics including
streptomycin (Str), ampicillin (Amp), ciprofloxacin (Cip), gentamycin (Gen) and
tetracycline (Te). Highest number of E. coli isolates showed resistance to gentamycin
(43%) followed by ampicillin (38%) and tetracycline (26%). In case of Salmonella spp.,
highest number of E. coli isolates showed resistance to gentamycin (31%) followed by
ampicillin (31%) and tetracycline (27%). This study revealed that water samples collected
from different cattle farms of Dhaka city were contaminated with multiple species of
multidrug resistant bacteria which may pose risk for both animal and human health.
Description:
A Thesis
Submitted to the Faculty of Animal Science and Veterinary Medicine
Sher-e-Bangla Agricultural University, Dhaka-1207,
In Partial Fulfillment of the Requirements for the Degree of
MASTER OF SCIENCE (MS) IN MICROBIOLOGY
