Baymenov Bakhit Muratovich, Bulashev Aitbay Kabykeshovich, Chuzhebayeva Gulzhagan Dzhambulovna, Aliyeva Gulnur Kozyevna, Beishova Indira Saltanovna, Kokanov Sabit Kabdyshevich, Raketsky Vitaly Anatolevich
Research Institute of Applied Biotechnology, A. Baitursynov Kostanay Regional University, Kostanai, Republic of Kazakhstan.
Department of Microbiology and Biotechnology, S. Seifullin Kazakh Agro Technical Research University, Astana, Republic of Kazakhstan.
Vet World. 2023 Sep;16(9):1815-1820. doi: 10.14202/vetworld.2023.1815-1820. Epub 2023 Sep 14.
is the most frequent and ubiquitous cause of mastitis in cows. In recent decades, antibiotic resistance has rapidly spread among infectious disease pathogens in Kazakhstan and globally. This study examined the phenotypic and genotypic resistance of . strains obtained from cattle milk to antibiotics.
In 2021 and 2022, 675 cow milk samples were collected from 16 dairy farms in Northern Kazakhstan. was identified using culture and biochemical methods. The nature of antibiotic resistance was determined by the disk diffusion (DD) method. The distribution of antibiotic resistance genes was determined by polymerase chain reaction.
Among the obtained isolates, high levels of resistance to β-lactam antibiotics (100%), tetracyclines (95.4%), fluoroquinolones (95.4%), and macrolides (60.92%) were observed. Meanwhile, the lowest levels of resistance were identified for sulfonamides (21.84%) and aminoglycosides (27.59%). All the obtained isolates were positive for the gene encoding thermonuclease. The , , and genes were detected in 45.9%, 77%, and 83.9% of the studied isolates, respectively.
The results indicate a high prevalence of antibiotic resistance in isolated from cows with clinical and subclinical forms of mastitis in Northern Kazakhstan. In addition, the prevalence of resistance was higher when evaluated by the DD method than when detecting the specific antibiotic resistance genes , , and , indicating the need for deeper analysis of the phenotypic and genetic determinants of antibiotic resistance.
是奶牛乳腺炎最常见且普遍存在的病因。近几十年来，抗生素耐药性在哈萨克斯坦及全球的传染病病原体中迅速传播。本研究检测了从牛乳中分离得到的菌株对抗生素的表型和基因型耐药性。
2021年和2022年，从哈萨克斯坦北部的16个奶牛场采集了675份牛乳样本。通过培养和生化方法进行鉴定。采用纸片扩散法（DD）确定抗生素耐药性的性质。通过聚合酶链反应确定抗生素耐药基因的分布。
在所获得的分离株中，观察到对β-内酰胺类抗生素（100%）、四环素类（95.4%）、氟喹诺酮类（95.4%）和大环内酯类（60.92%）的高水平耐药。同时，对磺胺类（21.84%）和氨基糖苷类（27.59%）的耐药水平最低。所有获得的分离株编码热核酸酶的基因均为阳性。在所研究的分离株中，分别有45.9%、77%和83.9%检测到、和基因。
结果表明，在哈萨克斯坦北部患有临床和亚临床型乳腺炎的奶牛中分离出的对多种抗生素具有高耐药率。此外，通过纸片扩散法评估的耐药率高于检测特定抗生素耐药基因、和时的耐药率，这表明需要对抗生素耐药性的表型和遗传决定因素进行更深入的分析。
