Antimicrobial resistance profiling and burden of resistance genes in zoonotic Salmonella isolated from broiler chicken.

BACKGROUND: Salmonella is frequently found in poultry of which only motile serovars have zoonotic significance due to their potential to induce human gastrointestinal infections. Antimicrobial resistance, being a public health concern, the emergence of multidrug-resistant (MDR) Salmonella serotypes affecting food chain has greater impact worldwide. AIM: Information on circulation of zoonotic Salmonella strains in commercial poultry farm level is limited in many parts of the world. This cross-sectional study was aimed to investigate the zoonotic Salmonella strains circulating in the broiler farm environment with their detailed antimicrobial resistance profiling. METHODS: Pooled faecal samples were collected randomly from commercial broiler farms of Chattogram district, Bangladesh. Standard bacteriological procedure was followed to isolate Salmonella, and identification was confirmed by genus specific polymerase chain reaction (PCR). After phenotypic characterisation of resistance profile against eight antimicrobials by disc diffusion technique, all strains were screened by PCR for some selected resistance genes. RESULTS: Out of the 350 samples, Salmonella was isolated and identified from 86 samples. In antimicrobial sensitivity testing, more than 98.8% isolates showed resistance to ampicillin and 94.2% to tetracycline followed by enrofloxacin (56%) and ciprofloxacin (50%). Notably, 94% isolates were found to be MDR. The results of PCR assays revealed that 81.4% of the isolates were carrying the tetA gene, 19.8% the tetB and 10.47% the tetC gene. The prevalence of the isolates bearing the blaTEM , blaCTX-M and Sul-I gene were 95.4%, 7.0 % and 37.2 %, respectively. CONCLUSION: There is a great risk to secure healthy poultry products due to the circulation of these MDR zoonotic Salmonella.

Isolation of multidrug-resistant Escherichia coli, Staphylococcus spp., and Streptococcus spp. from dogs in Chattogram Metropolitan Area, Bangladesh.

OBJECTIVES: Antibacterial resistance is a great concern in human and food animal medicine, and it poses a significant concern in pet animals like dogs. This cross-sectional study was conducted to evaluate the antimicrobial resistance pattern of Escherichia coli, Staphylococcus spp., and Streptococcus spp. along with the carryover of some resistance genes in E. coli from dogs in the Chattogram metropolitan area, Bangladesh. MATERIALS AND METHODS: Rectal swab (n = 50), nasal swab (n = 50), and skin swab (n = 50) samples were collected from dogs having respiratory infections, skin infections, and/or enteritis, respectively. Three types of bacteria were identified and isolated by conventional bacteriological techniques and biochemical tests. Antimicrobial susceptibility testing was carried out against 12 antimicrobials by disk diffusion methods. Six resistance genes, namely bla TEM, bla CTX-M, tetA, tetB, Sul-I, and Sul-II, were screened for phenotypically resistant E. coli isolates by the polymerase chain reaction. RESULTS: A total of 39 (78%) E. coli, 25 (50%) Staphylococcus spp., and 24 (48%) Streptococcus spp. isolates were isolated from the rectal swab, nasal swab, and skin swab samples, respectively. In the cultural sensitivity test, the E. coli isolates showed resistance to ceftriaxone (79%) and sulfamethoxazole/trimethoprim (64%). Doxycycline (80%) demonstrated the highest resistance among Staphylococcus isolates, followed by sulfamethoxazole/trimethoprim (60%). Streptococcus isolates showed the highest resistance to penicillin (63%), followed by ceftriaxone (54%), while no isolate showed resistance to gentamycin. The prevalence of bla TEM, bla CTX-M, tetA, tetB, Sul-I, and Sul-II genes in phenotypically resistant E. coli isolates were 100%, 61.29%, 100%, 8.33%, 56%, and 72%, respectively. CONCLUSIONS: Spillover of such multidrug-resistant bacteria and resistance genes from pet dogs pose a serious public health risk.

Impact of rice gruel on rumen metabolites and growth performance of sheep.

OBJECTIVES: We investigated the impact of rice gruel as an alternative energy source of molasses as well as measured the effectiveness of rice gruel on the physiology of the rumen environment and the growth performance of growing lamb. MATERIALS AND METHODS: A number of 18 sheep with an average age of 7 months and mean body weight of 5.9 kg were selected and divided into three groups for 60 days long feeding trial with urea molasses straw (UMS), urea rice gruel straw (URS), and concentrate feed. Every fortnight interval, live weight was recorded and rumen liquor from every group was collected four times before and after feeding at 4-h interval to examine the rumen environment. RESULTS: Color, odor, consistency, and protozoal motility remain unchanged in all three groups. The pH of the rumen liquor was highest at 8 h of post feeding among three groups. The bacterial count (6.1 × 1010) was higher in the group that consuming UMS than URS and concentrate feed. The rumen protozoa also showed a similar growth pattern in proportion to a number of rumen bacteria. At the end of the 60 days feeding trial, no significant differences (p ≤ 0.05) were found among the three groups in contrast to body weight gain. CONCLUSION: In the current feeding trial, the close similar effectiveness of rice gruel and molasses was found as a fermentable energy source. However, we suggest that rice gruel can be supplemented as a substitute for molasses under the situation when molasses are not available or expensive in field condition.