Mandakini R, Roychoudhury P, Subudhi P K, Kylla H, Samanta I, Bandyopadhayay S, Dutta T K
Department of Veterinary Microbiology, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Aizawl, Mizoram, India.
Department of Veterinary Microbiology, West Bengal University of Animal and Fishery Sciences, Kolkata, West Bengal, India.
Vet World. 2020 Dec;13(12):2752-2758. doi: 10.14202/vetworld.2020.2752-2758. Epub 2020 Dec 23.
The present study was conducted to record the prevalence of multidrug-resistant (MDR), extended-spectrum β-lactamases (ESBLs) producing from pig population of organized and unorganized farms of Mizoram and to record the presence of ESBLs, non-ESBLs, and integrons.
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 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.
A total of 258 was isolated and identified from organized (n=120) and unorganized farms (n=138). Majority of the 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. was most frequently (9.69%) gene, followed by -M (5.04%) and (0.78%). Altogether, 6 (5.00%), 4 (3.33%), and 2 (1.67%) isolates from the organized farms were positive for , , and genes, respectively. Similarly, 21 (15.22%) and 7 (5.07%) isolates from the unorganized farms were positive for and genes, respectively. None of them were positive for 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 , , , , , and genes, respectively. The prevalence of non-ESBLs genes was higher in the isolates from the unorganized farms than organized farms.
MDR and ESBLs producing 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.
本研究旨在记录米佐拉姆邦有组织和无组织养殖场猪群中多重耐药（MDR）、产超广谱β-内酰胺酶（ESBLs）的流行情况，并记录ESBLs、非ESBLs和整合子的存在情况。
从米佐拉姆邦有组织养殖场（n = 40）和无组织养殖场（n = 58）的猪采集粪便样本。通过传统技术、BD Phoenix™自动化细菌系统和基于聚合酶链反应（PCR）的确认试验对样本进行处理，以分离和鉴定细菌。所有分离株通过纸片扩散法进行抗菌药敏试验，并通过双纸片协同试验（DDST）检测ESBLs的产生情况。对产ESBLs的分离株进行PCR检测以确定ESBLs基因，对所有分离株通过PCR筛选非ESBLs基因和整合子。
从有组织养殖场（n = 120）和无组织养殖场（n = 138）共分离并鉴定出258株细菌。大多数分离株对阿莫西林（Ax）（81.78%）、头孢氨苄（85.42%）、复方新诺明（50.78%）、磺胺异恶唑（69.38%）、四环素（65.89%）和甲氧苄啶（TR）（51.94%）表现出高水平耐药。在Ax、氨苄西林、头孢氨苄、环丙沙星、复方新诺明、庆大霉素、哌拉西林和TR方面，有组织养殖场和无组织养殖场分离株之间的耐药性差异具有统计学高度显著性（p < 0.01）。通过DDST，65.89%的分离株被记录为产ESBLs菌株，其中82/120（68.33%）和88/138（63.77%）分别来自有组织养殖场和无组织养殖场。总共29/258（11.24%）的分离株至少一种ESBLs基因呈阳性。CTX-M是最常见的（9.69%）基因，其次是TEM - M（5.04%）和SHV（0.78%）。有组织养殖场中分别有6（5.00%）、4（3.33%）和2（1.67%）的分离株blaCTX-M、blaTEM和blaSHV基因呈阳性。同样，无组织养殖场中分别有21（15.22%）和7（5.07%）的分离株blaCTX-M和blaTEM基因呈阳性。它们中没有一株blaSHV基因呈阳性。总共57（22.09%）、9（3.49%）、66（25.58%）、78（30.23%）、21（8.14%）和18（6.98%）的分离株分别对blaOXA、blaPER、blaVEB、blaGES、blaIMP和blaVIM基因呈阳性。无组织养殖场分离株中非ESBLs基因的流行率高于有组织养殖场。
产MDR和ESBLs的细菌在米佐拉姆邦的猪及其环境中传播。无组织养殖场的猪对大多数抗菌药物，包括第三代头孢菌素，表现出较高水平的耐药性，这可能表明米佐拉姆邦无组织养猪部门存在抗生素过度使用或滥用的情况。
