Beyene Achenef Melaku, Nigatu Seleshe, Archila-Godinez Juan C, Amenu Kebede, Kowalcyk Barbara, Degefaw Desalegne, Mogess Binyam, Gelaw Baye, Gizachew Mucheye, Mengistu Araya, Abdelhamid Ahmed G, Barkley James, Yousef Ahmed
Department of Medical Microbiology, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.
Department of Veterinary Epidemiology and Public Health, College of Veterinary Medicine and Animal Sciences, University of Gondar, Gondar, Ethiopia.
J Food Prot. 2025 Feb 3;88(2):100446. doi: 10.1016/j.jfp.2024.100446. Epub 2024 Dec 28.
Contamination of milk is a serious public health risk, particularly in developing countries such as Ethiopia. Training is a tool for improving the quality and safety of milk. However, its effect on the microbial quality and safety of milk has not been well documented. This study assessed the impact of training interventions on the microbial quality and safety of milk, with a specific focus on smallholder dairy farms. The study was conducted from January to June 2022 in four locations in Central Ethiopia. Milk samples were collected from 120 dairy farmers one week before and four to six weeks after the training and analyzed for total coliforms, thermotolerant coliforms, Escherichia coli, Shiga toxin-producing E. coli (STEC), Salmonella enterica, and Campylobacter jejuni. Total and thermotolerant coliforms were determined by the Most Probable Number (MPN) method; categorized as high (≥1,001 MPN/ml), medium (101 10 MPN/ml), low (21-10 MPN/ml), and very low (≤20 MPN/ml); and analyzed using generalized linear mixed models. Prevalence of E. coli, STEC, S. enterica, and C. jejuni in raw milk samples were 67, 12, 3, and 4% pretraining and 45, 4, 3, and 2% posttraining, respectively. The prevalence of E. coli (p = 0.0389) and STEC (p = 0.0005) was significantly lower posttraining compared to pretraining. Most samples had total coliform counts exceeding 10 MPN/ml pretraining (71%); this proportion decreased to 62% posttraining. The estimated cumulative probability of being in the high category was marginally significantly higher (p = 0.0581) pretraining (76%) compared to posttraining (64%). In conclusion, reductions in the detection of some milk quality and safety parameters were observed. However, a considerable proportion of the milk samples were highly contaminated even after the training. Hence, comprehensive and continued risk mitigation strategies are needed to ensure milk safety for consumers.
牛奶污染是一个严重的公共卫生风险，在埃塞俄比亚等发展中国家尤为如此。培训是提高牛奶质量和安全性的一种手段。然而，其对牛奶微生物质量和安全性的影响尚未得到充分记录。本研究评估了培训干预措施对牛奶微生物质量和安全性的影响，特别关注小农户奶牛场。该研究于2022年1月至6月在埃塞俄比亚中部的四个地点进行。在培训前一周以及培训后四至六周，从120名奶农那里采集牛奶样本，并对其中的总大肠菌群、耐热大肠菌群、大肠杆菌、产志贺毒素大肠杆菌（STEC）、肠炎沙门氏菌和空肠弯曲菌进行分析。总大肠菌群和耐热大肠菌群通过最大可能数（MPN）法测定；分为高（≥1,001 MPN/ml）、中（101 - 10 MPN/ml）、低（21 - 10 MPN/ml）和极低（≤20 MPN/ml）四类；并使用广义线性混合模型进行分析。生牛奶样本中大肠杆菌、STEC、肠炎沙门氏菌和空肠弯曲菌的检出率在培训前分别为67%、12%、3%和4%，培训后分别为45%、4%、3%和2%。与培训前相比，培训后大肠杆菌（p = 0.0389）和STEC（p = 0.0005）的检出率显著降低。培训前，大多数样本的总大肠菌群计数超过10 MPN/ml（71%）；这一比例在培训后降至62%。估计处于高类别（≥1,001 MPN/ml）的累积概率在培训前（76%）略高于培训后（64%）（p = 0.0581）。总之，观察到一些牛奶质量和安全参数的检出率有所降低。然而，即使在培训后，仍有相当比例的牛奶样本受到高度污染。因此，需要全面且持续的风险缓解策略来确保消费者的牛奶安全。
