Background: Foodborne diseases are a huge social burden in both developed and underdeveloped countries. Escherichia coli is a natural inhabitant of the human and warm-blooded animal digestive tracts. It is considered as an indicator organism for direct or indirect faecal contamination of raw meats. The presence of antibiotic-resistant microorganisms in meat accounts for a public health risk. 
 
Methods: In current study, all 39 characterized E. coli isolates recovered on screening 405 fresh meat samples collected from different butcher shops in the Udgir city, Marathwada region of Maharashtra were also tested for Congo red dye binding assay and haemolysis assay. Antimicrobial resistance profiling of recovered isolates was carried out using the disc diffusion method. 
 
Result: Overall occurrence of E. coli in fresh meats was noted to the tune of 9.63% and the corresponding group wise occurrence in chicken and chevon samples were 12% and 7.32%, respectively. All E. coli tested positive in the Congo red dye binding assay and haemolysis assay, suggesting virulent nature of isolated organisms. On screening for antimicrobial resistance, these isolates were found resistant to mainly &acirc;-lactams (94.87%), lincosamides (84.62%), 4th Generation cephalosporins (82.05% each), DHFR Inhibitors (64.10%), glycopeptides (51.28%). The multidrug resistant isolates showed resistance to a minimum of 4 and maximum of 12 antibiotics with MAR index ranging from 0.27 to 0.8 and 9 resistance patterns.

The Occurrence, Antibiotic Susceptibility Pattern and Multiple Drug Resistance Index Studies of E. coli from Fresh Meats in Marathwada Region of Maharashtra

<div>Background:&nbsp;Salmonella is recognized as the most prevalent bacterial cause of foodborne diseases worldwide and animal-sourced foods have been reported as a common source of Salmonella infections among humans. 
 
Methods: The commercial chicken eggs, backyard chicken eggs, and duck eggs samples, 60 each, were processed for isolation and identification of Salmonella. All Salmonella isolates were further tested for resistance against six different antibiotics. The prevalence of virulence and antimicrobial resistance genes in the Salmonella isolates was determined by PCR. &nbsp; 
 
Result: A total of 28 Salmonella isolates were recovered with an overall prevalence of 15.6% and out of them, 11.1% and 4.4% were from eggshell and egg content, respectively. All the isolates were found sensitive to Gentamicin however maximum resistance was observed against Cefotaxime. PCR results revealed that 100% of the isolates were carrying the invA gene however stn gene was detected in 78.6% of isolates. Among presumptively identified &beta;-lactam-resistant Salmonella isolates, 100% and 50% isolates harbored blaTEM and blaCTX-M genes, respectively whereas none of the isolates contained the blaSHV gene. All tetracycline-resistant isolates harbored the tetA gene whereas none of the isolates carried the tetB gene. 100% of fluoroquinolone-resistant isolates were carrying the gyrA gene however parC gene was present only in 60% of isolates. These results indicate that drug-resistant Salmonella spp. were prevalent in eggs sold in the study area which can pose a serious public health problem.</div>

Antibiotic Resistance Pattern and Distribution of Resistance Genes in Salmonella Isolated from Chicken and Duck Eggs in Chhattisgarh, India

<div>Background: Mastitis is a problem of dairy animals including buffaloes. Treatment failure has become a common problem and the most cited reason is antibiotic resistance. The paper presents the scenario of antibiotic resistance with special reference to multi drug resistance pattern.&nbsp; 
 
Methods: Microbiological assay of mastitis affected 48 milk samples was carried out using standard protocols to establish the prevalence of mastitis caused by E. coli and S. aureus. Antibiotic sensitivity test was carried out against these organisms and the whole milk culture for commonly used antibiotics. The drug resistance pattern was established. 
 
Result: The overall prevalence of mastitis was 20%. The prevalence of E. coli and S. aureus was 29.17% and 54.17% respectively. The antibiotic sensitivity revealed that E.coli isolates were 100% susceptible to tetracycline, gentamicin, enrofloxacin and streptopenicillin followed by Ceftriaxone and sulbactum combination and streptomycin (92.86%) and ceftriaxone and methicillin (85.71%). The isolates of S. aureus were 100% sensitive to only two antibiotics gentamicin and streptopenicillin. The antibiogram of whole milk culture revealed maximum susceptibility to enrofloxacin, gentamicin and streptopeniciliin (95.83% each). Multiple drug resistance has been observed in this study.</div>

​Multidrug-resistance Pattern of Antibiogram of Escherichia coli and Staphylococcus aureus Isolated from Mastitis Affected Buffaloes in Eastern Uttar Pradesh

<div>Background: Salmonellosis is of great concern among the infectious diseases of poultry and has been responsible for serious economic losses to the poultry producers and a shift in Salmonella serotypes has been evident in recent years. Study was carried out to know the occurrence and pathology of Salmonellae infection in poultry along with their multi-drug resistance. 
 
Methods: Samples for study were collected from 26 organized poultry farms. To determine the presence of Salmonella in the farms, microbial culture from fecal swabs and pooled fecal samples was carried out for isolation of bacteria. Molecular detection of Salmonella isolates was also performed using direct PCR. Biofilm producing ability of the bacteria was also assessed and antibiotic sensitivity test was done to detect the resistance of bacterial isolates. 
 
Result: Salmonellosis in broiler and layer farms was recorded as 20% and 45.4% respectively and in 1.58% of the necropsy cases through microbial culture. Molecular detection of Salmonella isolates by PCR targeting invA gene was confirmed in 13.33% broiler farms and 36.3%-layer farms. Further detection of Salmonella Enteritidis was performed by PCR targeting ent gene and 11.11% positivity was determined. Biofilm producing ability of the bacteria was found 40% using biofilm assay. Serological examination using polyvalent antisera diagnosed 27.27% isolates as motile salmonellae. During necropsy of positive cases gross lesions comparable to salmonellosis were noted in liver, intestine, spleen and ovary. Multi-drug resistant (MDR) pattern was observed with highest resistance towards oxytetracycline, streptomycin followed by amikacin, amoxicillin and enrofloxacin. The presence of multiple drug resistant Salmonella in chicken has rendered the food chain unsafe from farm to table and hence continuous surveillance of the disease should be encouraged.</div>

Occurrence of Multi-drug Resistant Avian Salmonellae in Commercial Poultry

<div>Background: Multi-drug resistant Escherichia coli (E. coli) can cause a variety of diseases that lead to considerable economic losses in the swine industry. In the past, the mainstream view believed that most bacterial resistance was caused by planktonic bacteria, but the ability of bacteria to form biofilms was ignored. Here, we isolated and identified 185 strains of E. coli from pigs in central China and analyzed the relationship between their genetics, antibiotic sensitivity and biofilm formation ability. 
 
Methods: First, the isolates were classified according to biofilm formation ability by semi-quantitative staining of crystal violet. Then, Phylogenetic group analysis of isolates by polymerase chain reaction. In addition, E. coli with different biofilm-forming abilities were evaluated for antimicrobial susceptibility in its planktonic and biofilm state. Finally, the drug resistance pattern of the isolates with different biofilm formation capabilities were compared. 
 
Result: most of the collected strains showed biofilm formation ability (87.57%, 162/185). The isolated E. coli with biofilm formation ability were classified into the following groups: A (16.05%, 26/162), B1 (10.49%, 17/162), B2 (33.33%, 54/162) and D (40.12%, 65/162). Simultaneously, the isolated E. coli were classified into the following groups according to the biofilm formation ability: Strong (34.57%, 56/162), Moderate (33.33%, 54/162), Weak (32.10%, 52/162) and Absent (12.43%, 23/162). Compared with the planktonic cells, the isolates showed a significant increase in the resistance rate in the biofilm form. And the isolates of the strong biofilm-forming ability group had a high drug resistance pattern. This study provides data of the drug resistance of pig-derived E. coli with different biofilm-forming abilities and provides a scientific basis for guiding veterinary clinical treatment and disease prevention.</div>

<div>Effect of Biofilm Formation on the Escherichia coli Drug Resistance of Isolates from Pigs in Central China</div>

<div>Background: Non-typhoidal Salmonellae (NTS) are the predominant source of foodborne Salmonellosis in humans. Livestock and poultry are important reservoirs of NTS. In the context of food safety, this study was undertaken to characterize Salmonella species isolated from livestock, poultry and fish for antimicrobial resistance.&nbsp; 
 
Methods: A total of 620 fecal and food samples were randomly collected from different places. Isolation and identification of Salmonella species were done employing microbial and molecular tests. Phenotypic AMR pattern was studied as per the CLSI guidelines and AMR genes were detected by PCR.&nbsp; 
 
Result: Salmonella spp. were detected in 39(6.29%) out of 620 samples. Salmonella isolates were 100% sensitive to aztreonam, cefepime, cefpodoxime, followed by cefoxitin (97.43%), ceftazidime (94.43%), piperacillin/tazobactam (94.87%) and ciprofloxacin (71.79%). However, resistance to ampicillin (53.84%), colistin (66.66%), tetracycline (58.57%), amoxyclav (33.33%) and sulfafurazole (23.07%) was observed. Out of 39 isolates, 7(17.94%) were ESBL positive strains and blaTEM was detected in the two ESBL positive isolates. Quinolone- resistant QnrS gene was present in 3(7.69%) isolates. KPC, AmpC and MBL positivity and genes encoding mobile colistin resistance (mcr) were not detected. The presence of virulent and drug-resistant strains of Salmonella in livestock and poultry may poses environmental, food safety and public health risks.</div>

Antimicrobial Resistance Pattern of Salmonella Species Recovered from Livestock and Poultry

<div>Background: Antimicrobial resistance is one of the latest challenges facing the scientific community. Raising the drug resistance is caused mainly by indiscriminate usage of antibiotics in human and animal subjects and the spread of antibiotic resistance between the two has an emerging global threat. Hence, current study aimed to study the antimicrobial resistance pattern and molecular detection of antibiotic resistance genes in Staphylococcus aureus and Escherichia coli isolated from mastitis affected cows.&nbsp; 
 
Methods: Milk samples from mastitis affected cows were subjected to antibiotic sensitivity test and screened for presence of Staphylococcus aureus and Escherichia coli using differential growth media. Molecular characterization of Staphylococcus aureus and Escherichia coli was done with the help of PCR by amplification of &lsquo;nuc&rsquo; and &lsquo;uspA&rsquo; gene respectively. MICs of Penicillin and Tetracycline were determined using microdilution method.&nbsp; 
 
Result: Antibiotic sensitivity pattern for Penicillin G, Ampicillin, Amoxycillin, Cefotaxime, Ceftriaxone, Azithromycin, Ciprofloxacin, Gentamicin, Oxytetracycline, Tetracycline and Vancomycin were 74.19%, 100%, 93.50%, 61.29%, 29%, 35.48%, 9.70%, 9.70%, 70.96% and 70.96% &nbsp;respectively. More than 87.90% of the S. aureus and 50% of the E. coli isolated were resistant to &acirc;-lactam antibiotics while 75% of the E.coli and 65.70% of the S. aureus isolated were resistant to Tetracycline antibiotics. The MICs of Penicillin for S.aureus and E.coli are 26.88 &micro;g/ml and 13.54 &micro;g/ml respectively and the MICs of Tetracycline for S. aureus and E. coli are 243.75 &micro;g/ml and 960.93 &micro;g/ml respectively which is 8-9 folds higher than the standard MICs. From the present study, it can be inferred that bovine mastitis cases are highly resistant to antimicrobial drugs. Results further indicate that Staphylococcus aureus and Escherichia coli are both resistant to Penicillin and Tetracycline with very high MIC. &nbsp;</div>

<div>Molecular Characterization of Antibiotic Resistance Gene Pattern of Staphylococcus aureus and Escherichia coli in Mastitis Affected Dairy Cows</div>

Background: Multidrug resistant strains of Escherichia coli have been causing worldwide outbreaks of food borne diseases in recent years. The emergence of antibiotic-resistant strains of E. coli and the occurrence of transmissible drug resistance among the organism has amplified the complications associated with its control and treatment measures. Data associated with the prevalence, virulence factors and antimicrobial susceptibility of E. coli isolates are needed to be studied in order to develop an effective control strategy for colibacillosis in piggeries. The goal of the investigation was to study the antimicrobial susceptibility pattern and pathotyping of E. coli isolates from diarrhoeic piglets. 
 
Methods: 102 rectal swab samples were collected from diarrhoeic piglets of ICAR-AICRP/MSP on Pig, College of Veterinary Science, Assam Agricultural University, Khanapara, ICAR-National Research Centre on Pig, Rani, Guwahati, Assam and from different unorganized farms of the state. These samples were then inoculated in Luria Bertani (LB) broth and incubated aerobically at 37oC for 24 hours followed by sub culturing them in MacConkey&rsquo;s lactose agar (MLA) and Eosin Methylene Blue (EMB) agar for purification of the suspected E. coli isolates. The isolates were characterized by biochemical tests and motility tests and were pathotyped based on detection of specific virulence genes by multiplex Polymerase Chain Reaction (PCR). 
 
Result: Out of 102 rectal swab samples examined, 92 (90.2%) yielded E. coli which included 41 (91.12%) of 45 samples collected from ICAR-AICRP/MSP on Pig, College of Veterinary Science, Assam Agricultural University, Khanapara and 32 (88.89%) of 36 samples from ICAR-National Research Centre on Pig, Rani, Guwahati, Assam and 19 (90.48%) of 21 samples from different unorganized farms. All the 92 E. coli isolates were examined for the presence of stx1, est1, elt1 and eaeA genes using specific primers. Among these isolates, 25 (27.17%) were positive for stx1 gene, 18(19.56%) for est1 gene, 6(6.52%) for elt1 gene, 3 (3.26%) for both genes est1 and elt1 and 12 (13.04%) for eaeA gene. Antimicrobial susceptibility pattern of the isolates revealed that the highest percentage (71.74%) of the isolates were resistant to tetracycline and the least (4.34%) to imipenem.

Isolation, Pathotyping and Drug Susceptibility Pattern of Escherichia coli Isolates from Diarrheic Piglets

<div style="text-align:justify">Background: Trypanosomosis is a neglected tropical disease. Drug resistance in trypanosomosis has been on the increase in recent years. It is presumed that drug resistant trypanosomes are less pathogenic and may be very suitable for rodent models of human African trypanosomosis (HAT).&nbsp; 
 
Methods: The T. b. brucei used was locally isolated from a dog and characterized by PCR. Drug resistance trait of the isolate was evaluated using diminazine aceturate and isometamidium chloride. Healthy rats were inoculated with the isolate, IP. Some haemato-biochemical parameters were evaluated. Three rats were euthanized on day 70 PI and necropsied. Data generated from the study were analyzed by student&rsquo;s t-test and significance was accepted at probability, p&lt;0.05.&nbsp; 
 
Result: The isolate was confirmed to be drug resistant T. b. brucei and caused no mortalities in the infected rats. The low pathogenicity in rats was discussed and the typical CNS lesions of chronic-stage HAT produced by the isolate makes it a suitable candidate for rodent models of HAT.</div>

​​Pathogenicity of Drug-resistant Canine Isolate of Trypanosoma brucei brucei in Rats

Background: Multidrug-resistant pathogens are a significant cause of morbidity globally. The recent rise in resistant bacterial strains is largely attributed to the extensive use of antibiotics in human and animal treatment. In recent years, there has been a notable increase in drug-resistant Klebsiella pneumoniae strains, posing a major challenge for clinicians worldwide. 
 
Methods: In the current study, 121 samples were obtained from bovine mastitis milk and faeces, dairy cattle farm premises, chicken cloacal swabs, poultry farm litter and water. The samples were processed for the isolation and identification of Klebsiella species. Klebsiella isolates were identified by cultural, morphological and biochemical characteristics and were subsequently confirmed by PCR assays that targeted species-specific genes. The isolates were subjected to in vitro antibiotic sensitivity test. The DNA from all the isolates was extracted and subjected to PCR to identify the presence of 10 different Antibiotic Resistance Genes (ARG) using published primers. The ARGs targeted were blaTEM, blaSHV, blaOXA, blaIMP, DHAM, MOXM, tetA, tetB, sul1 and aadA. 
 
Result: Out of 121 samples, twenty-six (21.4%) samples were identified as Klebsiella pnuemoniae isolates. The occurence of Klebsiella pnuemoniae in samples from different sources was- 3/33 (09%) from mastitis milk, 8/27 (29.6%) from faecal samples and 04/14 (28.5%) from environmental samples collected from dairy farms. Similarly, Klebsiella pnuemoniae prevalence was recorded to be 6/33 (18.1%) in cloacal swabs and 5/14 (35.7%) from environmental samples collected from poultry farms. On in vitro antibiotic sensitivity test, all the Klebsiella pneumoniae isolates were found to be resistant to penicillin, amoxicillin, cefuroxime and ampicillin/ sulbactam (100% each), followed by cefalexin (65.3%), streptomycin (53.8%), tetracycline (38.4%), imipenum and co-trimoxazole (34.6% each), ofloxacin (30.7%), norfloxacin (27%), ceftriaxone (23%), amikacin (15.38%) and gentamicin (11.5%). All the K. pneumoniae isolates were found to be Multi Drug Resistant (MDR). Out of 26 isolates, 25 (96%) were positive for Sul1, 22 (84.6%) for blaTEM, 19 (73%) for blaSHV, 19 (3%) for tetA, 16 (61.5%) for aadA, 10 (38.4%) for OXA, 9 (34.6%) for tetB and 2 (7.6%) for DHAM and MOXM each. None of the isolates harboured blaIMP gene.