| مستخلص: |
In a series of experiments, pathogenic bacteria from poultry feeds and moribund hens’ reproductive organs were isolated and identified, and susceptibility of the bacteria to a number of antibiotics was assessed. Four types of branded poultry feeds available in Rajshahi City Corporation areas viz., broiler starter (BS), broiler grower (BG), layer starter (LS) and layer layer (LL) were collected from five randomly chosen shops. The feed samples were cultured in nutrient agar media and the bacterial specimens were isolated and examined under microscope for their gross morphological and biochemical characteristics. Results showed that the bacterial isolates belonged to Escherichia coli, Enterococcus sp. and Salmonella sp. Total viable counts (TVC) of the bacteria were replicated five times per feed and the BS, BG, LS and LL showed 23.40±2.88×1012, 28.60±1.52×1012, 83.20±7.40×1012, and 33.20±1.30×1012 cfumL-1 (colony forming units per millilitre), respectively. The highest TVC was recorded in LS where all three genera of the bacteria were found. In LL, on the other hand, E. coli and Salmonella sp. and in BS and BG, only Salmonella sp. was diagnosed. Sonali moribund hens were collected from five randomly selected poultry farms situated in Rajshahi metropolis. Samples of eggs, ovary and oviduct were suspended in physiological saline, one loopful of each suspension was inoculated separately into nutrient agar medium and the bacterial specimens were isolated and identified to be E. coli and Salmonella sp. TVC of bacteria in the eggs, ovary and oviduct samples yielded 100.40±3.96×1012, 72.20±3.35×1012 and 70.20±3.96×1012 cfumL-1, respectively. The highest TVC was recorded in the eggs, eggs and ovary specimens only had Salmonella sp. whereas oviduct contained E. coli and Salmonella sp. Finally, antibiotic sensitivity patterns of the bacterial isolates were tested against eight commonly used antibiotics viz., ampicillin (AMP), bacitracin (BAC), ceftriaxone (CEF), ciprofloxacin (CIP), doxycycline (DOX), gentamicin (GEN), sulphamethoxazole (SUL) and tetracycline (TET). E. coli showed resistance to BAC and SUL, Enterococcus sp. was highly resistant only to SUL while Salmonella sp. showed high to moderate resistance to AMP, GEN and SUL. The presence of three pathogenic bacteria in poultry feeds in Rajshahi, coupled with the diagnosis of E. coli and Salmonella in the reproductive organs of the moribund hens were indicative of bacterial contamination which reinforces the need for effective control measures against the pathogenic microbes, due care in handling of the poultry feeds and proper hygiene in the processing of the poultry meat and eggs for human consumption |
