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Aim: The present study was conducted to record the prevalence of multidrug-resistant (MDR), extended-spectrum β-lactamases (ESBLs) producing Escherichia coli from pig population of organized and unorganized farms of Mizoram and to record the presence of ESBLs, non-ESBLs, and integrons., Materials and Methods: Fecal samples were collected from pigs under organized (n=40) and unorganized (n=58) farms of Mizoram. Samples were processed for isolation and identification of E. coli by conventional techniques, BD Phoenix™ automated bacterial system, and polymerase chain reaction (PCR) based confirmatory test. All the isolates were subjected to antimicrobial sensitivity test by disk diffusion assay and ESBLs production by double-disk synergy test (DDST). The ESBLs producing isolates were subjected to PCR for determination of ESBLs genes and all the isolates were screened for non-ESBLs genes and integrons by PCR., Results: A total of 258 E. coli was isolated and identified from organized (n=120) and unorganized farms (n=138). Majority of the E. coli isolates exhibited high level of resistance against amoxicillin (Ax) (81.78%), cefalexin (85.42%), co-trimoxazole (50.78%), sulfafurazole (69.38%), tetracycline (65.89%), and trimethoprim (TR) (51.94%). Statistically highly significant (p<0.01) variations in resistance among the isolates from organized and unorganized farms were recorded in case of Ax, ampicillin, cephalexin, ciprofloxacin, co-trimoxazole, gentamicin, piperacillin, and TR. By DDST, 65.89% isolates were recorded as ESBLs producer, of which 82/120 (68.33%) and 88/138 (63.77%) were from organized and unorganized farms, respectively. A total of 29/258 (11.24%) isolates were positive for at least one ESBLs gene. bla TEM was most frequently (9.69%) gene, followed by bla CTX -M (5.04%) and bla CMY (0.78%). Altogether, 6 (5.00%), 4 (3.33%), and 2 (1.67%) isolates from the organized farms were positive for bla CTX-M , bla TEM , and bla CMY genes, respectively. Similarly, 21 (15.22%) and 7 (5.07%) isolates from the unorganized farms were positive for bla TEM and bla CTX-M genes, respectively. None of them were positive for bla SHV genes. Altogether 57 (22.09%), 9 (3.49%), 66 (25.58%), 78 (30.23%), 21 (8.14%), and 18 (6.98%) isolates were positive for tetA , tetB , sul1 , sul2 , aadA , and dfrla genes, respectively. The prevalence of non-ESBLs genes was higher in the E. coli isolates from the unorganized farms than organized farms., Conclusion: MDR and ESBLs producing E. coli are circulating among the pigs and their environment in Mizoram. Pigs under unorganized farms exhibited higher level of resistance against majority of the antimicrobials, including third-generation cephalosporins, which might be an indication of overuse or misuse of antibiotics under the unorganized piggery sectors in Mizoram., (Copyright: © Mandakini, et al.)

Aim: This study aimed to study the prevalence of the coinfection of enteric bacterial and viral pathogens, namely Escherichia coli, Salmonella , Rotavirus , and Picobirnavirus from fecal samples of pre-weaned piglets in Northeast region of India., Materials and Methods: A total of 457 fresh fecal samples were collected from piglets under 9 weeks old during 2013-2015 from organized (n=225) and unorganized (n=232) farms of Manipur, Meghalaya, Mizoram, and Nagaland. Samples were collected from diarrheic (n =339) and non-diarrheic (n=118) piglets including local indigenous (n=130) and crossbreed (n=327) piglets in different seasons during the study period. The samples were processed for the isolation of E. coli and Salmonella and detection of their putative virulence genes by polymerase chain reaction (PCR). Samples were also processed for the detection of Rotavirus and Picobirnavirus by RNA-polyacrylamide agarose gel electrophoresis and reverse transcriptase-PCR (RT-PCR)., Results: A total of 11 (2.40%) samples were found positive for two or more coinfecting enteric bacterial and viral pathogens. All the 11 positive fecal samples were recovered from diarrheic piglets. Salmonella Typhimurium (enterotoxin, stn gene) and Picobirnavirus genogroup 1 were found to be more frequent as coinfecting agents. Coinfection was recorded higher in unorganized (3.87%) compared to organized farm (0.88%). Again, higher detection was recorded in crossbreed (2.75%) than local indigenous piglets (1.53%). The occurrence of coinfection was found to be more common during summer (4.68%) followed by winter (2.27%) season., Conclusion: The present study highlighted the significance of E. coli , Salmonella , Rotavirus , and Picobirnavirus as important diarrheagenic pathogens causing coinfection in piglets in Northeast region of India. Probably, this is the first systematic study of the coinfection of four important diarrheagenic bacterial and viral agents associated with piglet diarrhea in India.

Aim: The present study was conducted to record the prevalence of extended spectrum β-lactamases (ESBLs) producing Escherichia coli , Salmonella spp., and Klebsiella pneumoniae from pig population of Assam and Meghalaya and to record the ability of the resistant bacteria to transfer the resistance genes horizontally., Materials and Methods: Fecal samples (n=228), collected from pigs of Assam (n=99) and Meghalaya (n=129), were processed for isolation and identification of E. coli and Salmonella spp. All the isolates were tested for ESBLs production by double disc synergy test (DDST) followed by screening for ESBLs producing genes ( bla TEM , bla SHV , bla CTX-M , and bla CMY ) by polymerase chain reaction (PCR). Possible transfer of resistance encoding genes between enteric bacterial species was carried out by in vitro and in vivo horizontal gene transfer (HGT) method., Results: A total of 897 enteric bacteria (867 E. coli and 30 Salmonella ) were isolated and identified. Altogether 25.41% isolates were confirmed as ESBL producers by DDST method. Majority of the isolates were E. coli followed by Salmonella . By PCR, 9.03% isolates were found positive for at least one of the target resistance genes. bla SHV was absent in all the isolates. bla CMY was the most prevalent gene. All the E. coli isolates from Assam were negative for bla TEM . A total of 2.76% isolates were positive for bla TEM + bla CMY . On the other hand, 0.67% isolates were positive for bla CTX-M + bla CMY genes. Only 0.33% isolates carried all the three genes. Altogether, 4.68% bacteria carried the resistance encoding genes in their plasmids. bla TEM gene could be successfully transferred from Salmonella (donor) to E. coli (recipient) by in vitro (5.5-5.7×10 -5 ) and in vivo (6.5×10 -5 to 8.8×10 -4 ) methods. In vivo method was more effective than in vitro in the transfer of resistance genes., Conclusion: The pig population of Assam and Meghalaya are carrying multidrug resistance and ESBLs producing E. coli and Salmonella . The isolates are also capable to transfer their resistance trait to other bacterial species by HGT. The present finding could be considered as a serious public health concern as similar trait can also be transmitted to the human commensal bacteria as well as pathogens.