Microbiological conditions of meats from large game animals and birds

Hunted Wild Boars in Sardinia: Prevalence, Antimicrobial Resistance and Genomic Analysis of Salmonella and Yersinia enterocolitica

The objective of this investigation was to evaluate Salmonella and Yersinia enterocolitica prevalence in wild boars hunted in Sardinia and further characterize the isolates and analyse antimicrobial resistance (AMR) patterns. In order to assess slaughtering hygiene, an evaluation of carcasses microbial contamination was also carried out. Between 2020 and 2022, samples were collected from 66 wild boars hunted during two hunting seasons from the area of two provinces in northern and central Sardinia (Italy). Samples collected included colon content samples, mesenteric lymph nodes samples and carcass surface samples. Salmonella and Y. enterocolitica detection was conducted on each sample; also, on carcass surface samples, total aerobic mesophilic count and Enterobacteriaceae count were evaluated. On Salmonella and Y. enterocolitica isolates, antimicrobial susceptibility was tested and whole genome sequencing was applied. Salmonella was identified in the colon content samples of 3/66 (4.5%) wild boars; isolates were S. enterica subs. salamae, S. ser. elomrane and S. enterica subs. enterica. Y. enterocolitica was detected from 20/66 (30.3%) wild boars: in 18/66 (27.3%) colon contents, in 3/66 (4.5%) mesenteric lymph nodes and in 3/49 (6.1%) carcass surface samples. In all, 24 Y. enterocolitica isolates were analysed and 20 different sequence types were detected, with the most common being ST860. Regarding AMR, no resistance was detected in Salmonella isolates, while expected resistance towards β-lactams (blaA gene) and streptogramin (vatF gene) was observed in Y. enterocolitica isolates (91.7% and 4.2%, respectively). The low presence of AMR is probably due to the low anthropic impact in the wild areas. Regarding the surface contamination of carcasses, values (mean ± standard deviation log10 CFU/cm2) were 2.46 ± 0.97 for ACC and 1.07 ± 1.18 for Enterobacteriaceae. The results of our study confirm that wild boars can serve as reservoirs and spreaders of Salmonella and Y. enterocolitica; the finding of Y. enterocolitica presence on carcass surface highlights how meat may become superficially contaminated, especially considering that contamination is linked to the conditions related to the hunting, handling and processing of game animals.

New insights in improving sustainability in meat production: opportunities and challenges

Treating livestock as senseless production machines has led to rampant depletion of natural resources, enhanced greenhouse gas emissions, gross animal welfare violations, and other ethical issues. It has essentially instigated constant scrutiny of conventional meat production by various experts and scientists. Sustainably in the meat sector is a big challenge which requires a multifaced and holistic approach. Novel tools like digitalization of the farming system and livestock market, precision livestock farming, application of remote sensing and artificial intelligence to manage production and environmental impact/GHG emission, can help in attaining sustainability in this sector. Further, improving nutrient use efficiency and recycling in feed and animal production through integration with agroecology and industrial ecology, improving individual animal and herd health by ensuring proper biosecurity measures and selective breeding, and welfare by mitigating animal stress during production are also key elements in achieving sustainability in meat production. In addition, sustainability bears a direct relationship with various social dimensions of meat production efficiency such as non-market attributes, balance between demand and consumption, market and policy failures. The present review critically examines the various aspects that significantly impact the efficiency and sustainability of meat production.

Use of Wild Boar (Sus scrofa) as a Sustainable Alternative in Pork Production

Pork production involves several sustainability issues. The recent increase in the natural wild boar population and the possibilities of its breeding to produce meat and for sport hunting have revived attention on this wild species. The most important factors that could account for its expansion and niche invasion are briefly summarized with the scientific opinion on management strategies. The information available to date on the quantitative, nutritional, and sensory characteristics of wild boar meat is reviewed to highlight its potential, if properly managed, as a sustainable option in meat production. This review reports on the opportunity of using wild boar meat in processed products and the need for research on processing qualities and acceptability for different final products. Above all, this review suggests that wild boar can be considered a sustainable alternative to meet the animal protein demand, as it can be established in marginal areas where it is already adapted to the environment, representing an interesting addition to traditional zootechnics.

Unexplained bacterial meat spoilage during the moose hunting in northern Norway - a review of cases 2008-2021

BACKGROUND

Sudden and unexpected spoilage of moose (Alces alces) carcasses has incidentally been reported in northern Norway. Hunters describe a strong foul odour and greenish discolouration of moose carcasses, hence the nickname "green moose". Finnmark Estate has registered all reported cases of "green moose" in Finnmark county in the period 2008-2021. In 2013, a questionnaire was introduced to gather more detailed information. Bacteriological and histological examinations were performed on submitted samples of spoiled moose meat. The aim of the present report is to summarize the data gathered about the "green moose" cases, and to discuss possible causes.

RESULTS

Ninety-three valid cases of "green moose" meat spoilage were registered in Finnmark county, giving this form of meat spoilage a prevalence of 0.85% of hunted moose. The carcass weights of spoiled carcasses were within normal weights for moose carcasses in Finnmark. Adult bulls were significantly more, and calves were less frequently affected by meat spoilage. No distinct geographical pattern or "hotspots" could be identified, but multiple cases in the same hunting area same year were reported. The meat spoilage was detected within 5 h after shooting in five cases, and 53% of cases were detected within 2 days after shooting. The meat spoilage was primarily found in deep muscle groups. Bacteriological analyses of 13 samples of spoiled meat were not conclusive. A mixture of aerobic bacteria was detected in 12 samples, and swarming clostridia in 10 samples. Histological examination of seven samples showed abundance of bacteria in fasciae and connective tissue surrounding blood vessels. Injury shootings were not more frequent in "green moose" cases than in moose hunting in general. Other possibly predisposing events to meat spoilage were evisceration later than 60 min after shooting, delayed skinning and contamination by ruminal content. Whether these events occurred more often in "green moose" than normal moose was difficult to determine, due to lack of reference data.

CONCLUSIONS

Based on the bacteriological results and the characteristics of the meat spoilage we suggest that clostridia are a main factor involved. How and why clostridia are spread to the muscles and causing the often rapid meat spoilage, is unexplained.

Microbiological quality and safety of vacuum-packaged white-tailed deer meat stored at 4 °C

Vacuum packaging is widely used for extending the shelf life of commercial fresh meat products. It also ensures product hygiene during distribution and storage. However, very little information exists concerning the effects of vacuum packaging on the shelf life of deer meat. One of our aims was to evaluate how storage under vacuum at 4 °C affects the microbial quality and safety of white-tailed deer (Odocoileus virginianus) meat cuts. This was assessed in a longitudinal study based on sensory analyses and measurements of (1) mesophilic aerobic bacteria (MAB), (2) lactic acid bacteria (LAB), (3) enterobacteria (EB), (4) and Escherichia coli (EC) counts, and the presence of foodborne pathogens (Campylobacter, Salmonella, stx-harbouring E. coli (STEC), Yersinia and Listeria). Microbiomes were additionally investigated by 16S rRNA gene amplicon sequencing at the time of spoilage. In total, 50 vacuum-packaged meat cuts from the carcasses of 10 wild white-tailed deer harvested in southern Finland in December 2018 were analysed. A significant (p < 0.001) drop in the odour and appearance scores and a significant increase in MAB (p < 0.001) and LAB (p = 0.001) counts of the vacuum-packaged meat cuts were observed after 3 weeks of storage at 4 °C. A very strong correlation (rs = 0.9444, p < 0.001) between the MAB and LAB counts were found during the 5-week sampling period. Clear spoilage changes, manifested as sour off-odours (odour scores ≤2) and pale colour, were detected in the meat cuts spoilt after 3-week storage. High (≥8 log₁₀ cfu/g) MAB and LAB counts were also detected. According to the 16S rRNA gene amplicon analyses, Lactobacillus was the dominant bacterial genus in these samples, demonstrating that LAB can cause rapid spoilage of vacuum-packaged deer meat cuts stored at 4 °C. The rest of the samples were spoilt after four or five weeks of storage, and a vast number of bacterial genera were identified in them. Listeria and STEC were detected by PCR in 50 % and 18 % of the meat cut samples, respectively, which may indicate a public health problem. Our results demonstrate that it is very challenging to ensure the quality and safety of vacuum-packaged deer meat stored at 4 °C, and freezing is therefore recommended to prolong the shelf life.

Molecular Detection of Tetracycline-Resistant Genes in Multi-Drug-Resistant Escherichia coli Isolated from Broiler Meat in Bangladesh

This study aimed to estimate the antimicrobial resistance (AMR) patterns and tetracycline-resistant gene profiles of Escherichia coli (E. coli) from broiler meat and livers sourced from live bird markets (LBMs) and supermarkets (SMs) in Chattogram, Bangladesh. In total, 405 samples were collected from SMs and LBMs, comprising muscle (n = 215) and liver (n = 190) samples. Disc diffusion tests were used to determine antimicrobial susceptibility profiles. PCR was used to identify E. coli and tetracycline-resistant genes. Over half (57%) of the chicken product samples were positive for E. coli. The AMR profiling of these isolates showed that the highest prevalence of resistance was against sulphamethoxazole-trimethoprim (89%), followed by tetracycline (87%), ampicillin (83%), and ciprofloxacin (61%). Among the antimicrobials listed by the World Health Organization as critically important, E. coli isolates were found to be resistant to cephalexin (37%), gentamicin (32%), and colistin sulfate (21%). A large proportion of E. coli demonstrated multi-drug resistance (MDR). Most (84%) of the tetracycline-resistant isolates encoded tetA. Of the remaining isolates, 0.5% encoded tetC, 6.0% encoded two genes, and 3.6% of isolates were tetD, which was newly identified by this study in Bangladesh. Broiler products in Bangladesh are frequently contaminated with multi-drug-resistant E. coli, with differential carriage of tetracycline genes. The prevalence of tetracycline resistance among E. coli indicates a concern for poultry health and welfare regarding the management of colibacillosis. It also indicates growing public health risks of AMR among broiler-associated pathogens, which can be transferred to humans via the food chain. Appropriate control measures should be developed and implemented, focused on the rational use of antimicrobials in poultry farming systems, to mitigate risk from this drug-resistant zoonotic pathogen from foods of animal origin and to protect public health.

The effect of storage method on selected physicochemical and microbiological qualities of wild boar meat

BACKGROUND

This study investigated the influence of the storage method on the physicochemical characteristics and microbial growth of m. longissimus thoracis et lumborum (LTL), m. biceps femoris (BF) and m. vastus lateralis (VL) of wild boar. Muscles were stored in a vacuum (VAC), in a modified high-oxygen atmosphere (MAP) or meat seasoning cabinet (DRY-AGED) for 21 days.

RESULTS

Wild boar meat was characterised by a high protein and low fat content and a good amount of potassium, sodium, calcium, magnesium, zinc and iron. Significantly higher (P < 0.05) pH values were noted for DRY-AGED muscles stored for 21 days (up to 5.89 for VL). On day 21, a significant decrease in pH was noted for all MAP muscles (down to 5.23 for BF). Storage losses due to desiccation and water loss were significantly higher for DRY-AGED samples and ranged from 25.63% to 32.89% on day 21. MAP affected protein and lipid oxidation, which was also reflected in Warner-Bratzler shear force VAC and DRY-AGED had positive results regarding tenderness, whereas on day 21 the MAP-stored meat had toughened significantly (from 35.3 N to 50.7 N in LTL). Lipids were oxidised much faster than proteins during prolonged storage in MAP. Compared to the other methods, DRY-AGED had the best effect on microbial growth.

CONCLUSION

These results indicate that the recommended methods for the storage of wild boar meat are either vacuum packing or dry ageing. The high oxygen content of MAP negatively affected the quality of wild boar meat and carried a risk of increased protein carbonylation. © 2022 Society of Chemical Industry.

Prevalence of virulence genes among Escherichia coli strains isolated from food and carcass swabs of different animal origins in Croatia

Introduction

Escherichia coli is present in the normal intestinal flora but some strains can cause intestinal and extraintestinal diseases, and research on its presence in food of animal origin is in the interests of public health. This study was designed to characterise E. coli strains according to their origin, their carriage of virulence genes specific for certain pathogroups, and phylogenetic group affiliation.

Material and Methods

The study was carried out on 100 E. coli strains isolated from food samples of various animal origin as well as pig and cattle carcass swabs. Isolation of the strains was performed using two methods. One method included colony count and the other an overnight enrichment of the samples. Isolation was followed by DNA extraction and detection of virulence genes and phylogenetic group with conventional and multiplex PCRs.

Results

In this study, the most prevalent gene was EAST1 (20%) and strains which carried it were identified as enteroadherent E. coli. Other pathogroups were represented in lower incidences. Phylogenetic group analysis revealed the prevalence of the A and B1 groups, with B1 mainly present in game and cattle strains, while the majority of pig and poultry strains were assigned to group A.

Conclusion

This study provides an overview of the presence of potentially pathogenic strains and E. coli phylogenetic groups in Croatia, for which the data are limited. Further microbiological and molecular research is required to examine the epidemiological situation in the country.

Salmonella in Wild Boars (Sus Scrofa): Characterization and Epidemiology

The large study on Salmonella spp. in the population of wild boars from twelve hunting estates in the South-West Vojvodina, Serbia was conducted with the aim to investigate the prevalence of Salmonella spp. in wild boars and to trace Salmonella sources. The hunting estates had similar epidemiological characteristics, i.e. lowland regions with an intensive management system of wild boars. The prevalence of Salmonella in wild boars was determined and the examination of molecular similarities of strains isolated from wild boars and domestic animals (pigs and poultry from nearby farms) was performed. The total number of 425 wild boars (25.3% of total population), shot on official hunts, were sampled (425 feces and 425 mesenteric lymph nodes samples) and examined by standard ISO protocols. Subtyping of the isolates was performed and compared by Pulsed-field gel electrophoresis (PFGE). The Salmonella prevalence in the fecal samples was 3.1% and in the lymph nodes was 0.2%. Salmonella Enteritidis was the most dominant serotype. A high molecular similarity was found between Salmonella isolates from wild boars and domestic animals. The proximity of communities and domestic animals, as well as improper removal of animal waste were identified as important epidemiological factors which significantly affect the epidemiology of Salmonella in wild boars from lowlands.

Safe Game: Hygienic Habits in Self-Consumption of Game Meat in Eastern Spain

We used anonymous questionnaires to assess the hygienic and sanitary aspects of game meat self-consumption in Eastern Spain as the first step towards a health risk assessment. The survey yielded 472 valid interviews from active hunters. The maximum possible score was 65 points (average 29 ± 8; range 1–52). Most participants were men (95%), but women achieved significantly better scores (p = 0.003). Hunters above 65 years old scored significantly lower results than younger groups (p = 0.007). The score increased with the educational level (p = 0.046). A 92% of the collaborators consumed game meat. Veterinary inspection and freezing were irregular among the participants. Most respondents declared carrying the animals in their personal vehicles. Of the dressing process, 61% of sites were outdoors, 68% of the participants declared using specific knives, 64% used the same clothes as in the field, and 42% used disposable gloves. The most usual way to dispose of the remains was garbage containers (41%); offal abandonment in the field was 33%, and 13% fed domestic animals using the remains. We conclude that public health authorities should increase their interest in the self-consumption of game meat. Clear guidelines about domestic dressing facilities and hygienic habits should be published, these being essential when looking for synergies with hunter associations.

An Introduction to Current Trends in Meat Microbiology and Hygiene

Purpose of Review

This editorial review aims to provide readers with an introduction to the Current Clinical Microbiology Report Special Issue “Meat Microbiology and Hygiene.” It will provide an overview of overarching trends and developments in this field, introduce the articles presented in this Special Issue, and attempt to offer a glimpse into the future of meat microbiology and hygiene.

Recent Findings

Meat production has been subjected to transformative changes within the last decade, and the focus of assuring meat safety has shifted to account for changing consumer demands as well as new microbial risks such as strains carrying antimicrobial resistance determinants.

Summary

Assuring that meat products meet high safety standards remains crucial to consumers worldwide. New risk-based meat safety assurance systems leveraging latest technological advances are needed to protect consumers and promote public health.

Improving Hunted Wild Boar Carcass Hygiene: Roles of Different Factors Involved in the Harvest Phase

Game meat production strongly differs from that of other meats, as peculiar factors present in the field and in the steps prior to transfer to a game-handling establishment can influence the hygiene of the carcasses and, therefore, of the meat. The effects of such factors were considered in hunted wild boars based on the main hygienic criteria adopted in meat processing. Environmental, animal, and hunting conditions were studied during two selective hunting seasons in Central Italy. A total of 120 hunted wild boar carcasses were sampled after the skinning process and analyzed for aerobic colony count, Enterobacteriaceae count, and Salmonella spp. isolation. The calculated mean values for aerobic colony and Enterobacteriaceae counts were 3.66 and 2.05 CFU/cm2, respectively, in line with the limits set for the meat of other ungulates by EU legislation. Salmonella spp. showed a prevalence of 2.5% (IC 95%: 1.72-3.27%). Statistical analysis of the data performed with the AIC criterion showed that the main parameter to consider for improving the hygienic level of carcasses is to reduce the time in the refrigerator before skinning, followed by hunting on cold days (<10 °C) without rain, hunting animals <60 kg, and reducing the time between shooting and evisceration.

Microbiological Changes in Meat and Minced Meat from Beavers (Castor fiber L.) during Refrigerated and Frozen Storage

This study aims to evaluate the microbiological status, pH, and water activity of European beaver meat to establish its shelf-life and microbiological safety. In this study, the microbiological profiles of meat and minced meat obtained from the carcasses of beavers were investigated. Microbial evaluation of the chilled meat was performed within 24 h after hunting, on the 7th day and 14th day, and the evaluation of the frozen meat was made during the 11th week of storage. Meat samples were analysed for total viable count (TVC), psychrotrophic bacteria count (PBC), Enterobacteriaceae count (EBC), Escherichiacoli count (EC), total staphylococcal count (TSC), lactic acid bacteria count (LABC) and total yeast and mould counts (TYMC). Tests for the presence of pathogenic bacteria from the genus Salmonella and Listeria were also performed. Additionally, the pH and water activity were determined. The initial amount of TVC was 4.94 log CFU/g in meat samples and 4.80 log CFU/g in minced meat. After 14 days of storage, the TVC increased to 8.33 in meat samples and 8.08 log CFU/g in minced meat. Pathogenic bacteria such as Listeria and Salmonella were not found in the beaver meat tested. The microbiological state of meat stored frozen for 11 weeks was comparable to the state found in meat stored refrigerated for seven days regarding the number of microorganisms.

Implications of Zoonoses From Hunting and Use of Wildlife in North American Arctic and Boreal Biomes: Pandemic Potential, Monitoring, and Mitigation

The COVID-19 pandemic has re-focused attention on mechanisms that lead to zoonotic disease spillover and spread. Commercial wildlife trade, and associated markets, are recognized mechanisms for zoonotic disease emergence, resulting in a growing global conversation around reducing human disease risks from spillover associated with hunting, trade, and consumption of wild animals. These discussions are especially relevant to people who rely on harvesting wildlife to meet nutritional, and cultural needs, including those in Arctic and boreal regions. Global policies around wildlife use and trade can impact food sovereignty and security, especially of Indigenous Peoples. We reviewed known zoonotic pathogens and current risks of transmission from wildlife (including fish) to humans in North American Arctic and boreal biomes, and evaluated the epidemic and pandemic potential of these zoonoses. We discuss future concerns, and consider monitoring and mitigation measures in these changing socio-ecological systems. While multiple zoonotic pathogens circulate in these systems, risks to humans are mostly limited to individual illness or local community outbreaks. These regions are relatively remote, subject to very cold temperatures, have relatively low wildlife, domestic animal, and pathogen diversity, and in many cases low density, including of humans. Hence, favorable conditions for emergence of novel diseases or major amplification of a spillover event are currently not present. The greatest risk to northern communities from pathogens of pandemic potential is via introduction with humans visiting from other areas. However, Arctic and boreal ecosystems are undergoing rapid changes through climate warming, habitat encroachment, and development; all of which can change host and pathogen relationships, thereby affecting the probability of the emergence of new (and re-emergence of old) zoonoses. Indigenous leadership and engagement in disease monitoring, prevention and response, is vital from the outset, and would increase the success of such efforts, as well as ensure the protection of Indigenous rights as outlined in the United Nations Declaration on the Rights of Indigenous Peoples. Partnering with northern communities and including Indigenous Knowledge Systems would improve the timeliness, and likelihood, of detecting emerging zoonotic risks, and contextualize risk assessments to the unique human-wildlife relationships present in northern biomes.

Food Safety Considerations Related to the Consumption and Handling of Game Meat in North America

Emerging foodborne pathogens present a threat to public health. It is now recognized that several foodborne pathogens originate from wildlife as demonstrated by recent global disease outbreaks. Zoonotic spillover events are closely related to the ubiquity of parasitic, bacterial, and viral pathogens present within human and animal populations and their surrounding environment. Foodborne diseases have economic and international trade impacts, incentivizing effective wildlife disease management. In North America, there are no food safety standards for handling and consumption of free-ranging game meat. Game meat consumption continues to rise in North America; however, this growing practice could place recreational hunters and game meat consumers at increased risk of foodborne diseases. Recreational hunters should follow effective game meat food hygiene practices from harvest to storage and consumption. Here, we provide a synthesis review that evaluates the ecological and epidemiological drivers of foodborne disease risk in North American hunter populations that are associated with the harvest and consumption of terrestrial mammal game meat. We anticipate this work could serve as a foundation of preventive measures that mitigate foodborne disease transmission between free-ranging mammalian and human populations.

Fatty acid profile, oxidative status, and content of volatile organic compounds in raw and cooked meat of different chicken strains

Chicken meat is rich in unsaturated fatty acids. Therefore, it is more susceptible to lipid oxidation and production of volatile organic compounds (VOC). In this study, we evaluated the fatty acids, antioxidants, and VOC profiles of raw and cooked meat samples derived from 4 strains of chicken differing in their growth rates, which were as follows: slow-growing (SG, Leghorn), medium-growing (MG, Hubbard and Naked Neck), and fast-growing (FG, Ross). The VOC profile of meat was measured using proton-transfer reaction–mass spectrometry (PTR–MS). The VOC were identified using PTR–time of flight-MS (PTR-ToF-MS). The data were analyzed using both univariate and multivariate models. Twenty main VOC were identified, which were classified into the following chemical categories: aldehydes, alkadienes, alkenes, furans, amides, alcohols, and other compounds. Our results revealed that the chicken genotype and the method of cooking strongly influenced the VOC profile of the meat. Identifying the relationships between these traits allowed us to highlight the trade-off of the main substrates such as n-3 and n-6 polyunsaturated fatty acids (PUFA), protective substances (antioxidants), and degradation products (VOC) of the poultry meat produced during cooking. The extent of VOC production and n-3 loss was found to be higher for the SG genotype. Reduction of n-6 was higher in MG, whereas small losses in antioxidants and PUFA were observed in the FG genotype, consequently, resulting in the lowest production of VOC. The SG and MG are genotypes more active from a kinetic point of view respect to the FG ones. For this reason, in the FG genotypes, the antioxidants are less involved in the oxidative stress induced by the movement; thus, they were available to protect the lipid of the meat during the cooking process. These results suggested that the use of SG and MG genotypes requires a specific dietary protocol (i.e., increasing the antioxidants content) to counteract the lipid oxidations in all the phases: in vivo, postmortem, and during/after cooking.

Fermented meat sausages from game and venison: what are the opportunities and limitations?

An increase in the acceptance, demand and production of game meat and venison has been experienced globally. Game meat and venison fit into consumers' ideology of healthy and environmentally friendly meat when compared to domesticated animals. Opportunities exist to explore the use of these meat sources in developing new products, particularly as game meat and venison in their fresh state are sometimes perceived as being tough. Consumers have shown a trend for trying exciting new products with different organoleptic qualities, and fermented sausages occupy a special niche in the gastro-economic trade. In this review, the production potential of game meat and venison and its prospective use in the development of fermented sausages are discussed. Emphasis is placed on the importance of meat characteristics in textural and sensorial development as well as the safety of fermented sausages. Additionally, consumers' perception of venison and game meat is discussed. Possible areas of research and knowledge gaps are highlighted, particularly the potential use of meat with high pH and microbial load. © 2018 Society of Chemical Industry.

Effects of Animal, Climatic, Hunting and Handling Conditions on the Hygienic Characteristics of Hunted Roe Doer (Caprelous capreolus L.)

The population of wild animals is increasing, and control strategies based on selective hunting are among the major options adopted. The game meat obtained is therefore available for controlled and certified valuable chains. The understanding of carcass contamination and the factors affecting it is therefore crucial to ensure meat safety and prolonged shelf-life. The carcass hygiene of 64 hunted wild male roe deer (Capreolus capreolus L.) was evaluated in relation to factors potentially affecting it. Aerobic colony and Enterobacteriaceae counts, as well as Salmonella spp. and Listeria monocytogenes detection, were performed. The interaction of the microbial determination with age and weight of the animals, the climate conditions, the shooting procedure, the time between the killing and the evisceration as well as the time of storage of the carcasses in refrigerated conditions before skinning, were evaluated. Neither Salmonella spp. nor Listeria monocytogenes were detected on the carcasses and the average loads detected were 3.39 ± 1.06 UFC/cm2 and 2.27± 1.11 UFC/cm2 for the aerobic colony count and Enterobacteriaceae count, respectively. The loads detected are similar to those reported by UE legislation for slaughtered species. The time of storage before skinning, the environmental temperature during hunting and the time between shooting and evisceration, associated with animal weight, affect the carcass hygiene and must be taken into careful consideration by hunters as food business operators.

Understanding spoilage microbial community and spoilage mechanisms in foods of animal origin

The increasing global population has resulted in increased demand for food. Goods quality and safe food is required for healthy living. However, food spoilage has resulted in food insecurity in different regions of the world. Spoilage of food occurs when the quality of food deteriorates from its original organoleptic properties observed at the time of processing. Food spoilage results in huge economic losses to both producers (farmers) and consumers. Factors such as storage temperature, pH, water availability, presence of spoilage microorganisms including bacteria and fungi, initial microbial load (total viable count-TVC), and processing influence the rate of food spoilage. This article reviews the spoilage microbiota and spoilage mechanisms in meat and dairy products and seafood. Understanding food spoilage mechanisms will assist in the development of robust technologies for the prevention of food spoilage and waste.

Microbial Load and Antibiotic Resistance Patterns of Escherichia coli and Enterococcus faecalis Isolates from the Meat of Wild and Domestic Pigeons

An expansion in the consumption of pigeon meat has occurred in recent years. However, little is known about microbial load and antibiotic resistance of this foodstuff. The hygiene status and the antibiotic resistance patterns (disc diffusion; Clinical and Laboratory Standards Institute, CLSI) of Escherichia coli and Enterococcus faecalis isolates from wild and domestic pigeon carcasses were investigated. Average microbial loads (log10 cfu/cm2) ranged from 1.40 ± 1.17 (fecal coliforms) to 3.68 ± 1.40 (psychrotrophs). The highest (p < 0.05) microbial loads were observed in domestic pigeons. No substantial differences were found between isolates from domestic and wild pigeons with regard to the prevalence of antibiotic resistance. Of the E. coli strains, 20.00% were susceptible, 25.00% showed resistance or reduced susceptibility to one antimicrobial and 55.00% were multi-resistant. Among the E. faecalis isolates, 2.22% were susceptible and 97.78% were multi-resistant. The greatest prevalence of resistance or reduced susceptibility among E. coli was observed for amoxicillin-clavulanic acid (20.00% strains), ampicillin (26.67%), streptomycin (55.00%) and tobramycin (20.00%). The prevalence of resistance or reduced susceptibility among E. faecalis ranged from 31.11% (trimethoprim/sulfamethoxazole) to 97.78% (erythromycin). Meat from pigeons is a major reservoir of antibiotic-resistant bacteria. The need for the correct handling of this foodstuff in order to reduce risks to consumers is underlined.

Factors affecting the microbiological load of Italian hunted wild boar meat (Sus scrofa)

This study investigates the microbiological conditions before maturation of wild boar meat (Sus scrofa) processed in approved game handling establishments in Italy. Fillets and legquarters of 37 carcasses were tested to assess Aerobic Colony Count (ACC), Enterobacteriaceae Count (EC) and Salmonella presence. Salmonella was never found and mean values of ACC and EC were 4.67 ± 1.78 SD and 2.60 ± 1.58 SD log CFU/cm², respectively. Both ACC and EC increased with time between evisceration and skinning, were significantly higher in fillets and when meat was processed by untrained operators. ACC also increased with boars' weight and when carcasses were cleaned with running potable water. Based on limits set by EU Regulation No 1441/2007 for pork meat, most legquarters resulted satisfactory or acceptable (59% for ACC and 70% for EC), while most fillets were unsatisfactory (76% ACC, 78% EC). Results show that the wild game meat supply chain can be a safe process when handling practices reported in European and National regulations are met.

Assessment of microbial communities on freshly killed wild boar meat by MALDI-TOF MS and 16S rRNA amplicon sequencing

Wild boars (Sus scrofa) are the most widely distributed large mammals and recent increase in consumption of wild boar meat urges the need of microbiological quality criteria. The aim of the study was to characterize the initial bacterial contamination on freshly-killed wild boar meat using a culture-dependent approach with ISO-methods combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry identification and 16S rRNA amplicon sequencing. Moreover, the presence of foodborne pathogens was examined using Real-Time-PCR and confirmed by classical isolation. Analysing 22 unrelated wild boar meat samples showed a higher bacterial contamination level compared to pork, with Salmonella present in almost one third of the samples. A great variability of the microbial contamination between the samples was recorded, as well as complementary results between culturing and 16S rRNA amplicon sequencing as frequently isolated genera were not always detected, and vice versa. Furthermore, the foodborne pathogen Salmonella was never detected with 16S rRNA amplicon sequencing, demonstrating the necessity for a cautious approach in the implementation of new analysis techniques in food safety. The present work determines that attention should be paid to the trade of non-inspected meat directly to retail or consumers.

Quality parameters of hunted game meat: Sensory analysis and pH monitoring

The aim of the present research is to propose a new, quick and objective method for the certification of hunted and/or culled wild game meat quality and to monitor its origin and the hunting practices adopted by hunters. The expected deliverable is a new labelling scheme for Italian hunted wild game meat that will guarantee high quality and safety standards for consumers and will decrease transaction costs of the supply chains. During the 2015, 2016 and 2017 hunting seasons, 1,056 hunted wild ungulates were sampled. Specifically, alpine chamois (n=537), roe deer (n=113), red deer (n=342) and wild boar (n=64), which were all hunted in the VCO2-Ossola Nord hunting district (Verbania Province, Piedmont, Italy). Samples of the longissimus dorsi were collected to evaluate the nutritional parameters and the acid profiles of the products. As a measure of meat quality, pH values have been recorded after slaughtering by inserting a probe in the semimembranosus muscle. The results were categorized as DFD (pH≥6,2), intermediate DFD (5,8≤pH<6,2) and high-quality meat (pH <5,8). As explanatory variables for the quality of wild game meat, differences based on age, gender and hunting practices were considered. Concerning the latter variables, measures were collected from animals received at hunting districts control centers by trained technicians who also collected information on the hunting practices, i.e., bleeding and evisceration of the carcasses and number of shots. Nutritional values showed low fat (<3 g per 100 g), low saturated fat (<1,5 g per 100 g) and high protein contents. Furthermore, wild game meat has high values of ω3 and CLA, ensuring a positive ω6/ω3 ratio. Differences were found in the concentrations of fat between age and gender, considering that during the mating season, adult males' weight loss can exceed 40%. Hunting practices seem to affect meat quality.

Analysis of bacterial contamination and antibiotic residue of beef meat from city slaughterhouses in East Java Province, Indonesia

Aim:

This research aimed to analyze the presence of microbial contamination and antibiotic residue in beef meat from city slaughterhouses in East Java Province, Indonesia.

Materials and Methods:

A total of 40 samples from city slaughterhouses were used in this study. The tests for microbial contamination used several methods including total plate count (TPC), most probable number of Escherichia coli, detection of Staphylococcus aureus using Mannitol Salt Agar media, Salmonella spp. detection using Bismuth Sulfite Agar media and Triple Sugar Iron Agar media, and detection of the antibiotic residue by screening tests.

Results:

Most of the samples were contaminated with E. coli (32.5% positive samples) and S. aureus (20.0% positive samples). The mean values of TPC and S. aureus contamination were lower than the maximum limit of contamination, which were 41.58 CFU/g and 13.93 CFU/g, respectively, while the mean value of E. coli contamination was 27.03 CFU/g which was higher than the maximum limit. A low frequency of TPC (5% positive samples) and Salmonella spp. contamination (2.5% positive samples) was found in meat samples. Meat samples from two of the surveyed slaughterhouses were tested positive for antibiotic residue and six of the 40 samples (15%) were also tested positive for the antibiotic residue.

Conclusion:

It was concluded that most of the microbial contamination in beef meat from city slaughterhouses was below the maximum limit of contamination and only two slaughterhouses were found antibiotic residues in the meat samples.

Changes in pH, colour and the microbiology of black wildebeest (Connochaetes gnou) longissimus thoracis et lumborum (LTL) muscle with normal and high (DFD) muscle pH

The effect of pH and the spoilage of black wildebeest Longissimus thoracis et lumborum (LTL) muscles with normal (pH > 6.06) and high pH (DFD; pH < 6.06) was investigated for 12 days under refrigerated (5 ± 1 °C) aerobic conditions. Results showed that pH affected colour, as initial values from Normal samples (L* = 33.08, a* = 13.60, b* = 10.29, C* = 17.10 and H_ab = 36.85) were greater than values for DFD meat (L* = 27.21, a* = 11.10, b* = 6.97, C* = 13.12 and H_ab = 32.08). Initial bacterial counts from DFD and Normal pH samples did not differ significantly. Over time, pH decreased for Normal and DFD samples until the 6th and 9th day, respectively, whilst both samples showed a significant decrease in redness and colour intensity. Aerobic bacteria and Enterobacteriaceae reached 7 log cfu/g > 4 days earlier than Normal pH samples and bacterial growth rate was >1.09-fold faster in DFD than Normal meat.

Consumer preferences for red deer meat: a discrete choice analysis considering attitudes towards wild game meat and hunting

This study aims to analyse consumer preferences for red deer meat (RDM) (Cervus elaphus) by conducting a case study in northern Italy. This analysis considers how the attitudes of consumers towards wild game meat and hunting might influence such preferences. This goal is achieved by combining the results of a k-means clustering analysis of the attitudes collected by means of two valuation scales with a discrete choice experiment (CE). According to our results, a positive attitude towards wild game meat has an effect on the willingness to pay (WTP) for RDM that is more than 3 times greater than being in favour of hunting. An analysis of the heterogeneity of consumer preferences allowed us to identify the presence of an important niche market for RDM served as carpaccio. Examining only the mean estimates for carpaccio without considering heterogeneity would lead to neglecting 18% of the sample with a positive willingness to pay for this attribute level.

Carcass and meat characteristics from farm-raised and wild fallow deer (Dama dama) and red deer (Cervus elaphus): A review

Deer species are utilised for food, hunting and other products throughout the world. Consumers are typically exposed to venison derived predominantly from both farm-raised or wild fallow (Dama dama) and red deer (Cervus elaphus). The production of venison under farm conditions, compared to the meat of deer hunted in the wild, allows for a regular supply of a consistently good meat. It is lean, tasty, and rich in proteins and minerals, with a low content of fat and cholesterol. Overall, the worldwide demand for meat is still growing, and both the potential of farming deer species and their use as meat producers have led to an increased interest in venison. The current knowledge about various factors (e.g. nutrition, age, sex, condition, season) affecting venison and game meat has significantly increased during past decades but information regarding the interaction between production system or pre- and post-slaughter handling and ultimate deer meat quality are still very limited.

The hygiene-sanitary control in the wild game meats

The use of game meat as a food source is currently a growing trend in our country. These products have strong and historic ties with cultural and culinary tradition, but are also appreciated for their sensory and nutritional characteristics. A major contributor to the supply of this type of product is hunting. Practiced since the dawn of time for survival, hunting has evolved into a recreational activity with substantial commercial interests. Of particular importance in this context is hunting of large ungulates. The progressive urbanization of the population has allowed for the re-establishment of bush and wooded areas that represent the ideal habitat of species such as the wild boar, whose numbers are increasing throughout the country. It is therefore clear that implementation of safety rules regarding the hunting and consumption of game meat needs to be urgently addressed. The understanding and application of rules isn’t always easy since the health law is intertwined with that of hunting, and the decision- making power left to the different regions does not contribute to a uniform application throughout the country. The aim of this study was to examine the norms that regulate the use of large wild game meat intended for human consumption and their applicability in hunting activities. From the comparison of the data reported in the literature and our field experience the rules implementation and the problems are evaluated. Operational procedures are then proposed to simplify some of the most difficult aspects and fill in the gaps highlighted.

A Review of Zoonotic Infection Risks Associated with the Wild Meat Trade in Malaysia

The overhunting of wildlife for food and commercial gain presents a major threat to biodiversity in tropical forests and poses health risks to humans from contact with wild animals. Using a recent survey of wildlife offered at wild meat markets in Malaysia as a basis, we review the literature to determine the potential zoonotic infection risks from hunting, butchering and consuming the species offered. We also determine which taxa potentially host the highest number of pathogens and discuss the significant disease risks from traded wildlife, considering how cultural practices influence zoonotic transmission. We identify 51 zoonotic pathogens (16 viruses, 19 bacteria and 16 parasites) potentially hosted by wildlife and describe the human health risks. The Suidae and the Cervidae families potentially host the highest number of pathogens. We conclude that there are substantial gaps in our knowledge of zoonotic pathogens and recommend performing microbial food safety risk assessments to assess the hazards of wild meat consumption. Overall, there may be considerable zoonotic risks to people involved in the hunting, butchering or consumption of wild meat in Southeast Asia, and these should be considered in public health strategies.

The effect of storage conditions on the hygiene and sensory status of wild boar meat

The aim of this study was to compare hygiene status of wild boar meat (shoulder and leg) stored up to 21days at 0°C, 7°C or 15°C. The microbial counts increased gradually in the expected sequence of increasing storage temperatures, with TVC at the end of storage ranging from approx. 2logCFU/g (0°C) to 5logCFU/g (15°C). The lactic acid bacteria and psychrotrophic microflora didn't exceed 2logCFU/g and 2.5logCFU/g, respectively. Whereas odor of the meat stored at 0°C and 7°C was still acceptable at the end of storage, the odor of the meat stored at 15°C was barely acceptable after only 7d of storage and also the content of ammonia was significantly higher. Game meat obtained from animals hunted in the correct way and stored at low temperatures had good microbiological and hygiene status which could be maintained for more than 15days of storage.

Genotypic and antimicrobial characterization of pathogenic bacteria at different stages of cattle slaughtering in southern Brazil

Meat can be contaminated in different stages of the slaughtering process and the identification of these stages is the starting point to implement adequate control measures. The objectives of this study were to assess the presence of pathogenic microorganisms in cattle carcasses, to identify the most important contamination points of the slaughtering process, and to evaluate the possible risk factors related to them in a cattle slaughterhouse. To this aim, 108 cattle carcasses were sampled at three stages of the slaughtering process: Point 1 (hides after bleeding); Point 2 (carcasses after hide removal); and Point 3 (carcasses immediately after division). Escherichia coli O157:H7, Listeria monocytogenes and Salmonella Livingstone were isolated from the carcasses. Phenotypic and genotypic characterization indicated that there was cross-contamination among animals, since bacteria with identical genotypic and phenotypic profiles were isolated from different animals at the same sampling day. Furthermore, this is the first report about the isolation of E. coli O157:H7 in a bovine slaughterhouse from southern Brazil.

Meat from wild boar (Sus scrofa L.): a review

Wild boar is a species that is utilised for food and sport hunting throughout the world. Recent increases in natural populations and the potential of farming wild boars have stimulated interest in this species as a meat producer. Compared to domestic pigs, wild boars present a higher degree of carcass fatness and larger loin areas, more slow-twitch oxidative (I) and fast-twitch oxidative glycolytic (IIA) and less fast-twitch glycolytic (IIB) muscle fibres, and darker, less tender and leaner meat. Differences in diets might contribute to differences in cooked meat flavour and fatty acid composition between wild boars and domestic pigs. Higher α-tocopherol concentrations in wild boar might extend its meat shelf-life. Mechanical massaging of muscles, vacuum package ageing and addition of marinates have been attempted to tenderise wild boar meat. Further research on hunting protocols for wild boar, and value-added products from its meat, are needed.