The missing process hygiene criteria in the game meat chain: challenges in wild boar meat production

Wild boars are one of the most common large wild mammals globally. Their remarkable adaptive capacity and ecological plasticity, as well as human-related factors enable them to achieve high population densities, result in significant environmental, economic, social, and public health challenges. This human-wild boar conflict underscores the need for effective management strategies. Hunting is the most effective control method; it has increased culling rates and meat yields, presenting an opportunity to develop a game meat supply chain with numerous potential benefits. However, wild boars are reservoirs of foodborne pathogens and antimicrobial-resistant bacteria, while the hunting process itself involves variables that can affect carcass contamination. Despite these risks, process hygiene criteria for game meat are not currently defined in Regulation (EC) No 2073/2005. This study aimed to evaluate the hygiene criteria set for carcasses of livestock species, i.e. Aerobic Colony Count (ACC), Enterobacteriaceae Count (EntC), and Salmonella, in wild boars hunted in Emilia-Romagna region (Italy). Furthermore, it included Escherichia coli as a hygiene indicator by assessing its prevalence, ESβL and carbapenemen- resistance, and pathotype profiles. During the 2022/2023 and 2023/2024 hunting seasons, a total of 115 sponge samples from wild boar carcasses and 78 diaphragm muscle samples from a proportion of the same animals were collected across eight game-handling establishments (GHEs). Biometric data of the wild boars, along with hunting process variables, including the killing methods, the time between killing, evisceration, and skinning, as well as the carcass storage temperatures, were recorded. The mean values of ACC and EntC were 4.22 log₁₀ CFU/cm² and 2.27 log₁₀ CFU/cm², respectively. The prevalence of Salmonella was 3.48%, with isolates identified as Salmonella Coeln, Salmonella Typhimurium, and Salmonella diarizonae O:50 (z). Resistance in Salmonella was detected only against sulfamethoxazole in one Salmonella diarizonae O:50 (z) isolate. Hunting-related factors included the different GHEs, and the time between killing, evisceration, and skinning significantly influenced carcass contamination. The prevalence of E. coli was 97.43%. No resistance to third-generation cephalosporins or carbapenem was observed. Concerning, E. coli pathotypes, 3.33% were classified as atypical enteropathogenic E. coli (aEPEC), 3.33% as enteroaggregative E. coli (EAEC), and 93.3% as atypical enteroaggregative E. coli (aEAEC). Even in absence of criteria for wild game species, the overall values for ACC, EntC, and the prevalence of Salmonella could be deemed “acceptable” within the Regulation (EC) No 2073/2005. Nevertheless, the results of the study emphasize that the interval between killing and evisceration should ideally be kept under 3 hours, with evisceration to skinning not exceeding 10 hours. Completing the entire process within 4 hours, however, is preferable. Furthermore, our results confirm that wild boars serve as reservoirs for pathogens such as Salmonella and pathogenic E. coli. This study underscores the need for standardized microbiological hygiene criteria at the EU level for game meat, as well as integrated control measures throughout the hunting process.