This systematic review aimed to compile the available body of knowledge about microbiome-related nutritional interventions contributing to improve the chicken health and having an impact on the ...reduction of colonization by foodborne pathogens in the gut. Original research articles published between 2012 and 2022 were systematically searched in Scopus and PubMed. A total of 1,948 articles were retrieved and 140 fulfilled the inclusion criteria. Overall, 73 papers described 99 interventions against colonization by Escherichia coli and related organisms; 10 papers described 15 interventions against Campylobacter spp.; 36 papers described 54 interventions against Salmonella; 40 papers described 54 interventions against Clostridium perfringens. A total of 197 microbiome-related interventions were identified as effective against one or more of the listed pathogens and included probiotics (n = 80), prebiotics (n = 23), phytobiotics (n = 25), synbiotics (n = 12), organic acids (n = 12), enzymes (n = 4), essential oils (n = 14) and combination of these (n = 27). The identified interventions were mostly administered in the feed (173/197) or through oral gavage (11/197), in the drinking water (7/197), in ovo (2/197), intra amniotic (2/197), in fresh or reused litter (1/197) or both in the feed and water (1/197). The interventions enhanced the beneficial microbial communities in the broiler gut as Lactic acid bacteria, mostly Lactobacillus spp., or modulated multiple microbial populations. The mechanisms promoting the fighting against colonization by foodborne pathogens included competitive exclusion, production of short chain fatty acids, decrease of gut pH, restoration of the microbiome after dysbiosis events, promotion of a more stable microbial ecology, expression of genes improving the integrity of intestinal mucosa, enhancing of mucin production and improvement of host immune response. All the studies extracted from the literature described in vivo trials but performed on a limited number of animals under experimental settings. Moreover, they detailed the effect of the intervention on the chicken gut without details on further impact on poultry meat safety.
Purpose of Review
This review focuses on key foodborne helminths: providing an overview of their lifecycles and major transmission routes to humans, their geographical distribution, clinical ...manifestations, human health burden and control aspects.
Recent Findings
Many foodborne helminths appear to be increasing in geographical distribution, driven by climatic and demographic changes; predominately increases in global humidity and temperature, favouring environmental survival and changes in human consumption practices, exposing many more people to high-risk foodstuffs. Although current estimates of human health burden indicate the need for us to focus on these diseases it is acknowledged that poor diagnostic performance and inefficient surveillance leads to an underestimate of burden and for some highly neglected helminths no burden estimates have been performed. It is acknowledged that intervention strategies should consider the full value chain and involve multiple stakeholders following a ‘One Health’ approach.
Summary
As well as improving burden estimates, key research needs for foodborne helminths include the need for improved diagnostic tools and better integration of the social sciences to ensure the development of contextually relevant and socially acceptable control strategies.
Interventions to control or eradicate neglected zoonoses are generally paid for through the public purse and when these interventions focus on the animal hosts, they are often expected to be ...performed and financed through the state veterinary service. The benefits of control, however, accrue across the human, animal, and environmental spaces and enhance both public and private interests. Additionally, disease control interventions do not take place in a vacuum and the indirect impacts of our actions should also be considered if the societal benefit of interventions is to be maximised. With the caveat that unintended consequences can and will occur, pre-identifying potential synergies and trade-offs in our disease control initiatives allows for them to be considered in intervention design and monitored during programme roll-out. In this paper, using a One Health approach with the example of
control, we identify potential indirect impacts which may arise and how these may influence both our choice of intervention and opportunities to optimise the animal, environmental, and societal benefits of control through maximising synergies and minimising trade-offs.
Dry-aged meat is gaining popularity among food business operators and private consumers. The process is carried out in aerobic conditions by hanging beef carcasses or placing subprimal or primal cuts ...in a dedicated cabinet for several weeks or even months while controlling the environment through the management of process parameters such as temperature, relative humidity, and airflow. In this review, we present a critical evaluation of the literature to evaluate tools to manage the process to guarantee food safety and identify critical control points, as well as good hygienic and manufacturing practices. In controlled aging conditions, only Listeria monocytogenes and Yersinia enterocolitica can multiply, while a reduction in the number of Salmonella spp. and Escherichia coli O157:H7 is generally reported. Enterobacteriaceae usually decrease on the surface of the meat during maturation; thus, for the purpose of the hygienic evaluation of the production process, a count no higher than that of unmatured meat is expected. Besides, various studies report that the total bacterial count and the spoilage microorganisms significantly increase on the surface of the meat, up to 5-6 Log CFU/g in the absence of visible spoilage. Bacteria of the Pseudomonas genus tend to progressively replace other microorganisms during maturation; thus, the total mesophilic or psychrophilic bacterial load is not a good indicator of process hygiene for matured meat. Critical parameters for the control of the process are temperature, relative humidity, and ventilation, which should be monitored during the process. For this reason, equipment designed and certified for dry aging must be used, and the manufacturer must validate the process. Food business operators must apply general good manufacturing practices (GMP) and good hygiene practices (GHP) for meat processing and some GMP and GHP specific for dry aging. Several research needs were identified, among them the evolution of the populations of L. monocytogenes and Y. enterocolitica and the microbiology of the inner parts of the dry-aged meat.
The human population is growing and urbanising. These factors are driving the demand for animal-sourced proteins. The rising demand is favouring livestock intensification, a process that frequently ...relies on antibiotics for growth promotion, treatment and prevention of diseases. Antibiotic use in livestock production requires strict adherence to the recommended withdrawal periods. In Kenya, the risk of residues in meat is particularly high due to lack of legislation requiring testing for antibiotic residues in meat destined for the local market. We examined pig carcasses for gross pathological lesions and collected pork samples for antibiotic residue testing. Our aim was to determine if a risk-based approach to residue surveillance may be adopted by looking for an association between lesions and presence of residues. In total, 387 pork samples were tested for antibiotic residues using the Premi
Test micro-inhibition kit. The prevalence of antibiotic residues was 41.26% (95% CI, 34.53-48.45%). A logistic regression model found no significant associations between gross pathological lesions and the presence of antibiotic residues. We recommend that the regulating authorities strongly consider routine testing of carcasses for antibiotic residues to protect meat consumers. Future studies should research on farming practices contributing to the high prevalence of residues.
In modern food industry settings, pathogenic microorganisms such as Shiga-toxin producing Escherichia coli (STEC) cause global public health concerns. Foodborne infections with STEC are common, and ...sporadically linked to venison consumption. This article reviews the scientific literature on wild deer culled for human consumption, to outline the factors that influence the carriage of STEC in the intestines of wild deer species and the practices that lead to venison contamination. It discusses the potential risk factors, from culling on the hill to final packaging, linked to this pathogen. The review found important variables influencing the presence of STEC in deer carcasses and venison. Many of these were unrelated to human intervention, being generally linked to the condition of the live animal and the probability of bacterial shedding. Other factors influencing STEC presence related to the management of the environment and dressing hygiene practices, both of which can be optimised to reduce the risk of contamination. We also highlight gaps in the current understanding of the risk related to parts of the wild venison chain that could impact on the microbial quality of food products derived from wild deer carcasses. An industry approach that considers integrating the scientific evidence collated in this review into the traditional knowledge of the hill-to-fork chain would assist in adapting the businesses’ food safety management system to better mitigate the possibility of STEC contamination in venison products intended for human consumption.
•Warm ambient temperatures are associated with higher STEC shedding in wild deer.•High deer population density, exposure to other ruminants increase STEC shedding.•Abdominal wounding and intestinal tears increase the risk of STEC transfer to meat.•Contamination may be more difficult to avoid in larger, male wild deer carcasses.•Contamination from the terminal rectum may have greater food safety implications.
Taenia saginata is a zoonotic tapeworm of humans with bovines as its intermediate host (bovine cysticercosis). Traditional meat inspection is the main measure to identify the larval stage in ...carcasses and prevent human infection, but has a notoriously low sensitivity, especially in low prevalence settings. The legislation in multiple African countries mandates an incision in both triceps brachii muscles to detect the parasite as part of the normal post-mortem inspection, but this has an economic cost and is not universally mandated in other countries. The primary aim of this study was to investigate the epidemiology of bovine cysticercosis at an export abattoir in South Africa and determine the validity and cost of the triceps incision. Risk factors were investigated, and the effect of additional heart incisions on the current inspection. Four incisions were made into the heart in addition to the normal post-mortem inspection in 3353 carcasses. The proportion of positive animals with and without the cardiac and triceps incisions were compared using McNemar’s chi-square tests, while risk factors were assessed using binary logistic regression. The economic impact of the triceps incision was estimated using a stochastic economic cost model. Thirty-three positive carcasses were identified for an apparent prevalence of 0.98 % (95 %CI, 0.69–1.36 %), while the true prevalence was estimated at 6.6 % (95 %CI, 4.3–8.8 %). All cysts were confirmed as T. saginata on histopathology with 70 % (95 %CI, 53–83 %) located in the heart. The additional cardiac incisions resulted in the detection of significantly more cases compared to the normal inspection method prevalence of 0.72 % (95 %CI, 0.47–1.05 %; P < 0.001). The apparent prevalence of T. saginata when omitting the triceps incision was not significantly lower compared to the prevalence when included in the inspection (P = 0.480). External feedlots (OR= 4.17, 95 %CI: 2.04–8.54, P < 0.001) and older animals (OR=3.90, 95 %CI: 1.17–13.03, P = 0.027) were associated with a positive detection. The current median annual financial cost to the food business operator from the triceps incision was estimated at $30387 (95 %CI: $0-$130696), with the proportion of deboned meat exported identified as the most important factor affecting cost (Spearman’s rho=0.853). The identification of risk factors could aid in the development of a more effective risk-based inspection system. The current inspection should be modified to increase exposure of the heart and remove the triceps incisions. The latter should especially be considered given the minimal contribution to cysticercosis detection, the unsupported requirement for its inclusion specifically in Africa, and its economic impact, especially as beef exports increase.
The commercialization of processed fish products is rising in restaurants and small to medium enterprises. However, there is a lack of data related to the microbiological safety of such products. In ...this study total aerobic colony count and Enterobacteriaceae, as proxy of process hygiene criteria, and detection of Listeria monocytogenes and concentration of histamine, as food safety criteria, were investigated in Salmo salar (salmon), Xiphias gladius (swordfish) and Thunnus albacares (yellowfin tuna), before, during, and at the end of a dry-curing process, performed in a dedicated cabinet, at controlled temperature, relative humidity and ventilation, up to 240 h. The microbiological parameters were investigated in the tested fish products by culture methods and shotgun metagenomic, while the presence of histamine, and other biogenic amines, was quantified by High Performance Liquid Chromatography.
In the raw material, and up to the end of the dry curing process, the concentration of Enterobacteriaceae was always lower than 10 CFU/g, while total aerobic colony counts ranged between 3.9 and 5.4 Log CFU/g in salmon; 5.5 and 5.9 Log CFU/g in swordfish; 4.4 and 4.8 Log CFU/g in tuna. The pH values were significantly different between fish species, in the raw materials and during processing except for T4, occurring 70 h after the start of the process for salmon and after 114 h for swordfish and tuna. Water activity was different at specific sampling points and at the end of processing. Overall, 79 % of the sequences identified in the tested fish samples were assigned to y bacteria. The most abundant phyla were Pseudomonadota, Bacillota and Mycoplasmatota. The microbial populations identified by shotgun metagenomic in the tested fish species clustered well separated one from the other. Moreover, the microbial richness was significantly higher in salmon and tuna in comparison to swordfish.
Listeria monocytogenes was not detected in the raw material by using the reference cultural method and very few reads (relative abundance <0.007) were detected in swordfish and tuna by shotgun metagenomic. Histamine producing bacteria, belonging to the genera Vibrio, Morganella, Photobacterium and Klebsiella, were identified primarily in swordfish. However, histamine and other biogenic amines were not detected in any sample.
To the best of our knowledge this is the first paper reporting time point determinations of microbiological quality and safety parameters in salmon, swordfish and tuna, before, during and at the end of a dry-curing process. The data collected in this paper can help to predict the risk profile of ready to eat dry-cured fish products during storage before consumption.
•In dry-cured fish Enterobacteriaceae were always <10 CFU/g.•Fish superficial pH and aw differed among fish species.•The prevalent phyla were Pseudomonadota, Bacillota and Mycoplasmatota.•Listeria monocytogenes was not detected in raw fish and at the end of dry-curing.•Histamine producing bacteria were identified but histamine was not detected.
Wild deer hunting is necessary in Scotland to control deer population density, with most carcasses being processed for human consumption. As limited information is available on the microbial ...condition of Scottish venison, we studied the variation of total coliforms and Escherichia coli (E. coli) on 214 wild deer carcasses collected from six approved establishments. Samples were collected from the hide, body cavity and external surface of each carcass and mean values were determined following bacterial plate counts. The mean log10/cm2 coliforms were 5.78 (hide), 6.80 (body cavity) and 6.36 (external surface). The mean log10/cm2E. coli were 1.82 (hide), 2.27 (body cavity) and 2.17 (external carcass). Significantly higher coliforms counts were associated with storage-to-dressing times above 6 days and with longer transport distances. Risk factors that increased E. coli were red deer species, ambient temperature above 7 °C during hunting, dirty hides, faecal contamination and moisture or slimy film on the carcass. Although the bacterial counts obtained in this study indicated some hygienic processing, for around half of the carcasses, the E. coli counts were above 2 log10/cm2. Therefore, the above risk factors suggest a few handling hygiene practices that should be further improved to enhance quality and safety.
•Carcasses storage of more than 6 days led to significantly higher coliform counts.•Ambient temperature above 7 °C was associated with higher E. coli counts.•The hygienic condition of the hide significantly increased the E. coli values.•E. coli counts were higher for carcasses that presented a moist or slimy film.•Red deer had significantly higher E. coli compared with roe deer.
Although visiting an abattoir is mandatory for all UK veterinary students, this was challenging during the COVID-19 pandemic and virtual simulators were temporarily approved by the Royal College of ...Veterinary Surgeons. Subsequently, the virtual slaughterhouse simulator (VSS) was used by the University of Nottingham School of Veterinary Medicine and Science, the University of Liverpool School of Veterinary Science and the Royal (Dick) School of Veterinary Studies in Edinburgh. This study aimed to evaluate the student learning experience using the VSS.
An online survey containing satisfaction and assessment questions was distributed to all final-year students who used the VSS from September 2020 to August 2021.
A total of 207 students completed the survey (n = 207/488, 42%). Students were mostly highly satisfied and found the VSS very useful for their learning (n = 164/207,79%); however, anxiety levels to visit a real abattoir lowered for less than half of the students (n = 97/207, 46%). Most students obtained an overall mark over 50% in the assessment questions (n = 197/207, 95%).
Although the findings were very positive, extrapolation to other veterinary schools and postgraduate curricula should be done cautiously.
The VSS is a valid tool for training veterinary students. However, more research is advised to compare virtual and real experiences and assess students' long-term performance.
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