摘要

肯尼亚鲁鲁地区家禽场沙门氏菌和大肠杆菌分离株流行情况及耐药性分析

作者(年代):Dorica Gakii Ngai

家禽饲料中的沙门氏菌和大肠杆菌对家禽和人类健康都有危害。家禽饲料在初级生产、饲料混合和动物饲养过程中受到污染。在家禽饲料中微生物的控制和预防中，建立用于饲养家禽的家禽饲料的微生物安全性是非常重要的。沙门氏菌是全球食源性疾病的主要来源之一。这是由于食用了受污染的家禽产品，包括禽蛋和禽肉。沙门氏菌会引起胃肠炎、伤寒和腹泻等疾病。大多数沙门氏菌血清型不是宿主特有的，在动物和人类中引起疾病。沙门氏菌和大肠杆菌对化学治疗和抗菌药物有耐药性是很常见的。沙门氏菌和大肠杆菌的主要食品污染是由于饲料原料在食品加工过程中与灰尘混合造成的。因此，家禽饲料可以被认为是沙门氏菌和大肠杆菌进入家禽群的主要转移途径。 The objectives of this study were to determine prevalence, assess microbial load in poultry feeds, antimicrobial resistance levels and assess resistant genes of Salmonella sp. and Escherichia coli isolated from poultry feeds from selected outlets in Ruiru Sub - County. A total of 150 poultry feed samples of different poultry feed were collected from 30 randomly selected poultry feed outlets from five sampling sites in Ruiru Sub - County. Microbial load was determined by serial dilution. Isolation of Salmonella sp. and Escherichia coli was carried out using Salmonella-Shigella, Xylose Lysine Deoxycholate and MacConkey agar and confirmed with biochemical tests. Antimicrobial susceptibility screening was done using Kirby-Bauer disc diffusion technique. The detected drug resistance isolates were confirmed by molecular screening for specific resistance genes based on the targeted antibiotic using PCR. Tukey’s HSD was used to separate the means of bacterial counts using SPSS software version 20. The bacterial load ranged from3.1x105 cfu/g to 3.0x106 cfu/g. The bacterial load was significantly different among the samples collected (p=0.0001). Out of the 150 samples of poultry feeds, 28 % were detected with Salmonella sp. and 58 % with Escherichia coli. The isolates manifested resistance to tetracycline, co-trimoxazole and ampicillin. The resistant isolates of Salmonella sp. and Escherichia coli carried dfr, strb, tem and shv genes. The study reveals high levels of bacterial load and resistant bacteria that carry antimicrobial resistant genes in poultry feeds. Therefore, hygienic handling and production of poultry feed is important to minimize bacterial contamination in poultry feed which is a health hazard to poultry and humans. Use of antimicrobial agents in poultry production should also be regulated to reduce antimicrobial resistance.