Search

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 (≥1001 MPN/ml), medium (101 to 10 3 MPN/ml), low (21 to 10 2 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% pre-training and 45, 4, 3 and 2% post-training, respectively. The prevalence of E. coli (p = 0.0389) and STEC (p = 0.0005) was significantly lower post-training compared to pre-training. Most samples had total coliform counts exceeding 10 3 MPN/ml pre-training (71%); this proportion decreased to 62% post-training. The estimated cumulative probability of being in the high category was marginally significantly higher (p = 0.0581) pre-training (76%) compared to post-training (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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Bifidobacterium bifidum is one of the most abundant members of the gut microbiota at the early stage of life. The established association of the bacterium with the human gut confers health benefits. Such successful persistence of B. bifidum necessitates metabolic adaptation to the host-derived carbohydrates, a process which is poorly understood. The current study focuses on revealing the genomic-based phylogeny (phylogenomics) of B. bifidum and utilizing comparative genomics to decipher the glycolytic abilities of bifidobacterial strains isolated from different human body niches (feces, human gut, vagina, and breast milk). When the phylogenomic analysis was performed on 95 B. bifidum strains, currently available on the RefSeq database, the bacterium was clearly distinguished from other members of the Bifidobacterium genus. Furthermore, a pairwise genomic comparison indicated that a large proportion of orthologous gene families were shared among the B. bifidum strains. These findings highlight the notion that the B. bifidum species is genetically similar and may perform similar functions in their host. When 15 B. bifidum genomes representing strains from different human body niches were annotated, the resulting functional profile showed the presence of enriched proteins involved in carbohydrate utilization. Moreover, mining the 15 B. bifidum genomes for the presence of Carbohydrate-Active Enzyme (CAZY) systems, the analysis found the existence of diverse protein families which include glycosyl hydrolases, glycosyl transferases, carbohydrate-binding modules, and carbohydrate esterases. Collectively, these CAZY systems enables B. bifidum to utilize host-derived glycans (e.g., mucin) and diet-derived carbohydrates (e.g., starch). In contrast, a correlation analysis revealed that B. bifidum strains isolated from the different body niches were indistinguishable in the context of presence-absence of CAZY systems. These findings emphasize the valuable use of comparative genomics in deciphering the glycolytic abilities of B. bifidum and consequently its adaptation to carbohydrate utilization in the human gut environment., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2021 Elsevier Inc. All rights reserved.)