Field efficacy of a novel porcine reproductive and respiratory syndrome modified-live virus vaccine with an emphasis on growth performance.

BACKGROUND: This field evaluation was designed to evaluate the efficacy of a new porcine reproductive and respiratory syndrome virus-2 (PRRSV-2) modified live virus vaccine at three independent pig farms. METHODS: Three farms were selected for this study based on their respiratory disease status caused by PRRSV-2 infection in post-weaning and growing pigs. Each farm housed a total of 40, 18-day-old pigs that were randomly allocated to one of two treatment groups. Pigs were administered a 1.0 mL dose of the bivalent vaccine intramuscularly at 21 days of age in accordance with the manufacturer's recommendations, whereas unvaccinated pigs were administered a single dose of phosphate buffered saline at the same age. RESULTS: Vaccinated groups were measured and calculated significantly (p < 0.05) higher in body weight and average daily weight gain on all three farms compared with unvaccinated groups. Vaccinated groups elicited PRRS antibodies and PRRSV-2-specific interferon-γ secreting cells, which reduced the amount of PRRSV-2 genomic copies in the blood and reduced macroscopic and microscopic lung lesions severity when compared with unvaccinated groups. CONCLUSIONS: The field evaluation data demonstrated that a new PRRSV-2 modified live virus vaccine was efficacious in swine herds suffering from respiratory diseases caused by PRRSV-2 infection.

Evaluation of commercial ELISA kits' diagnostic specificity for FAST diseases in wild animals.

Wild animals, sharing pathogens with domestic animals, play a crucial role in the epidemiology of infectious diseases. Sampling from wild animals poses significant challenges, yet it is vital for inclusion in disease surveillance and monitoring programmes. Often, mass surveillance involves serological screenings using enzyme-linked immunosorbent assay (ELISA) tests, typically validated only for domestic animals. This study assessed the diagnostic specificity of commercially available ELISA tests on 342 wild ruminant serum samples and 100 from wild boars. We evaluated three tests for foot-and-mouth disease: two for Peste des petits ruminants, two for Rift Valley fever and one for Capripox virus. Diagnostic specificity was calculated using the formula True Negative/(False Positive + True Negative). Cohen's kappa coefficient measured agreement between tests. Results showed high specificity and agreement across all tests. Specificity for foot-and-mouth disease (FMD) ranged from 93.89% for Prionics to 100% for IDEXX, with IDvet showing 99.6%. The highest agreement was between FMD IDvet and IDEXX at 97.1%. Rift Valley fever (RVF) tests, Ingezim and IDvet, achieved specificities of 100% and 98.83%, respectively. The optimal specificity was attained by retesting single reactors and inactivating the complement.Contribution: Commercially available ELISA kits are specific for foot-and-mouth disease and similar transboundary animal diseases and can be used for highly specific wild animal testing.

Spatio-temporal clustering of African swine fever virus (Asfarviridae: Asfivirus) circulating in the Kaliningrad region based on three genome markers.

INTRODUCTION: The rapid spread of African swine fever in the Kaliningrad region makes it necessary to use the methods of molecular epidemiology to determine the dynamics and direction of ASF spread in this region of Russia. The aim of the study was to determine single nucleotide polymorphisms within molecular markers K145R, O174L and MGF 505-5R of ASFVs isolated in Kaliningrad region and to study the circulating of the pathogen in European countries by subgenotyping and spatio-temporal clustering analysis. MATERIALS AND METHODS: Blood samples from living domestic pigs and organs from dead domestic pigs and wild boars, collected in the Kaliningrad region between 2017 and 2022 were used. Virus isolation was carried out in porcine bone-marrow primary cell culture. Amplicons of genome markers were amplified by PCR with electrophoretic detection and subsequent extraction of fragments from agarose gel. Sequencing was performed using the Sanger method. RESULTS: The circulation of two genetic clusters of ASFV isolates on the territory of the Kaliningrad has been established: epidemic (K145R-III, MGF 505-5R-II, O174L-I - 94.3% of the studied isolates) and sporadic (K145R-II, MGF 505-5R-II, O174L-I - 5.7%). CONCLUSION: The broaden molecular genetic surveillance of ASFV isolates based on sequencing of genome markers is necessary in the countries of the Eurasian continent to perform a more detailed analysis of ASF spread between countries and within regions.

Perceptions and practices of Swedish wild boar hunters in relation to African swine fever before the first outbreak in Sweden.

BACKGROUND: The first outbreak of African Swine Fever (ASF) in Sweden was detected in 2023 in wild boar. This study was conducted before the first ASF outbreak with the objective of investigating Swedish hunters' perceptions and practices pertaining to ASF ahead of any potential future outbreak. A mixed-methods interview study with Swedish wild boar hunters, consisting of focus group discussions and a questionnaire, was undertaken between October 2020 and December 2021. Six focus groups were conducted online, and an online questionnaire with questions related to practices and habits concerning hunting, the use of bait and hunting trips was sent to all members of the Swedish Hunting and Wildlife Association. A total of 3244 responses were received. RESULTS: Three general themes were identified in a thematic analysis of the data from the focus groups: hunters are willing to engage in ASF prevention and control, simplicity and feasibility are crucial for the implementation of reporting, sampling and control measures, and more information and the greater involvement of the authorities are required in ASF prevention and control. Results from the questionnaire showed that the use of bait was common. Products of animal origin were rarely used for baiting; the most common product used was maize. Hunting trips abroad, especially outside of the Nordic countries, were uncommon. CONCLUSIONS: Hunting tourism and the use of bait do not seem to constitute a major risk for the introduction of ASF to wild boar populations in Sweden. The accessibility of relevant information for each concerned stakeholder and the ease of reporting and sampling are crucial to maintain the positive engagement of hunters.

Sow dimensions and loose-housed farrowing pen sizes on commercial piglet-producing farms in Sweden.

International interest in loose-housed farrowing is growing and there are ongoing discussions within the European Union (EU) on new legal requirements. However, there is a lack of empirical data on loose-housed farrowing pen sizes and sow dimensions in commercial production. The aim of this study was to map and describe sow size and loose-housing farrowing pen size on commercial piglet-producing farms in Sweden. The study included 146 sows and 51 pen types on 35 medium sized to large Swedish piglet-producing farms (ranging from 106 to 1300 sows in production). Sow length ranged from 129 to 238 cm (mean ± SD 191.3 ± 19.3 cm) and sow height from 74 to 133 cm (86.7 ± 7.7 cm). Floor space occupied by the sow when lying down (length x height) ranged from 1.0 to 3.2 m2 (1.7 ± 0.3 m2). Pen length ranged from 259 to 415 cm (315.1 ± 24.3 cm), pen width from 188 to 245 cm (207.0 ± 10.7 cm), total pen area from 5.7 to 8.9 m2 (6.5 ± 0.5 m2), piglet corner area from 0.5 to 1.8 m2 (1.1 ± 0.4 m2) and area available for the sow (total area - piglet corner area) from 3.9 to 6.4 m2 (5.4 ± 0.6 m2). These results show that there is substantial variation in sow, pen and piglet corner size on commercial piglet-producing farms in Sweden. This poses a risk of mismatches between sow and pen size (pens too short in relation to sow dimensions), especially for older sows. These findings are of practical significance for animal welfare and production and emphasise the importance of designing loose-housed pens adapted to future sow, litter and piglet size.

Domestication and exposure to human social stimuli are not sufficient to trigger attachment to humans: a companion pig-dog comparative study.

Dogs exhibit human-analogue attachment to their owners, with similar function and mechanisms to that of infant-mother bond, but its origin is unclear. Comparative studies on socialised wolves and dogs emphasise genetic influence in dogs' preparedness for attachment to humans. We aimed to reveal if this genetic effect stems from general domestication or artificial selection that increased dogs' dependence on humans. We assessed and compared behavioural patterns of young companion pigs and dogs using a Strange Situation Test. Dogs but not pigs exhibited distinct behaviours towards their owner and a stranger along attachment-specific variables, so only dogs' relevant behaviours fulfilled attachment criteria. From the observed behaviours, three factors were formed: Attachment (to the owner), Anxiety (in a strange situation), and Acceptance (of a stranger). Results indicate (1) higher Attachment scores in dogs than pigs, (2) greater Acceptance scores in pigs, (3) positive correlation of Attachment and Anxiety in both, (4) similar time tendency of pigs' Attachment and Acceptance scores. These suggest that in pigs, domestication and early exposure to human social stimuli did not trigger attachment to humans. Thus, along with species predispositions, the unique dog-owner attachment can be facilitated by artificial selection that increased dogs' dependence on humans.

Tracking the phylogenetic profile of HEV in swine and wild boar in Europe.

Hepatitis E virus (HEV) infection is prevalent among domestic pigs and wild boar in Europe. This study focused on the genetic diversity of HEV subtypes 3c, 3e and 3f among swine and wild boar in Europe as well as their circulation. Phylogenetic analysis and Bayesian phylogenetic inference were applied on the selected ORF2 capsid HEV sequences to co-estimate the viral circulation, the mean evolutionary rates and the dated trees. The estimated mean values of the HEV ORF2 capsid gene evolutionary rate were 8.29 x 10-3, 5.96 x 10-3, and 1.107 x 10-2 substitutions/site/year, respectively for 3c, 3e and 3f. The majority of the HEV 3c and 3e supported clusters did not show intermixing between swine and wild boar. Thus, although the intermixing observed in a minority of HEV 3c and 3e supported clusters suggests that transmission/circulation of these subtypes between swine and wild boar can potentially occur, 3c and 3e European wild boar HEV populations remained mainly segregated. In contrast, one half of the HEV 3f supported clusters showed intermixing between swine and wild boar, providing evidence for transfer/circulation to swine. The data suggest that continued virologic surveillance in swine and wild boar is necessary, together with targeted measures to reduce the chance of HEV transmission to humans.

Epidemiological factors conditioning sarcoptic mange spreading in wild boar (Sus scrofa).

Sarcoptic mange is a widely distributed disease, with numerous potential hosts among domestic and wild animals. Nowadays it is considered a neglected re-emergent infection in humans. As a difference with domestic pigs, and even with several clinical cases reported in some European countries, it seems that Eurasian wild boars (Sus scrofa) have a low susceptibility to clinical mange. However, because of a case of confirmed transmission from Spanish ibex (Capra pyrenaica) to wild boar in the province of Tarragona, we planned a large-scale ELISA survey in the neighboring Valencian Community (SE Spain). We compared 419 wild boar sera from different management systems (fenced vs. open game estates), different ages (piglets, juveniles, and adults), with different behaviour (gregarious females of all ages and male piglets vs. solitary juveniles and adult males), from areas with different wild boar densities, different wild ruminant densities and different sarcoptic mange epidemiologic situations. The whole prevalence of antibodies against sarcoptic mange in the tested wild boars was 10.5%. No significant differences were found when comparing fenced and free ranging wild boars, males and females, gregarious vs. solitary individuals or among different ages. However, wild boar density was a relevant factor. In areas with a hunting bag of <1 wild boar/km2, considered as a low density of suids, the seroprevalence was 2.94%, but rose to 11.52% in high density districts, constituting a significant difference (p = 0.037). Low wild boar populations would act as a protective factor (OR 0.233; p = 0.049) against coming into contact with the mite. The wild ruminant densities or their sarcoptic mange status did not show any effect on wild boars seroprevalence against this disease. These results reinforce the suggested host-taxon Sarcoptes scabiei specificity and the independence of host-species foci.

Multi-omic characterization of allele-specific regulatory variation in hybrid pigs.

Hybrid mapping is a powerful approach to efficiently identify and characterize genes regulated through mechanisms in cis. In this study, using reciprocal crosses of the phenotypically divergent Duroc and Lulai pig breeds, we perform a comprehensive multi-omic characterization of regulatory variation across the brain, liver, muscle, and placenta through four developmental stages. We produce one of the largest multi-omic datasets in pigs to date, including 16 whole genome sequenced individuals, as well as 48 whole genome bisulfite sequencing, 168 ATAC-Seq and 168 RNA-Seq samples. We develop a read count-based method to reliably assess allele-specific methylation, chromatin accessibility, and RNA expression. We show that tissue specificity was much stronger than developmental stage specificity in all of DNA methylation, chromatin accessibility, and gene expression. We identify 573 genes showing allele specific expression, including those influenced by parent-of-origin as well as allele genotype effects. We integrate methylation, chromatin accessibility, and gene expression data to show that allele specific expression can be explained in great part by allele specific methylation and/or chromatin accessibility. This study provides a comprehensive characterization of regulatory variation across multiple tissues and developmental stages in pigs.

Comparative evaluation of disease dynamics in wild boar and domestic pigs experimentally inoculated intranasally with the European highly virulent African swine fever virus genotype II strain "Armenia 2007".

Since the reintroduction of African swine fever virus (ASFV) in Europe in 2007 and its subsequent spread to Asia, wild boar has played a crucial role in maintaining and disseminating the virus. There are significant gaps in the knowledge regarding infection dynamics and disease pathogenesis in domestic pigs and wild boar, particularly at the early infection stage. We aimed to compare domestic pigs and wild boar infected intranasally to mimic natural infection with one of the original highly virulent genotype II ASFV isolates (Armenia 2007). The study involved euthanising three domestic pigs and three wild boar on days 1, 2, 3, and 5 post-infection, while four domestic pigs and four wild boar were monitored until they reached a humane endpoint. The parameters assessed included clinical signs, macroscopic lesions, viremia levels, tissue viral load, and virus shedding in nasal and rectal swabs from day 1 post-infection. Compared with domestic pigs, wild boar were more susceptible to ASFV, with a shorter incubation period and earlier onset of clinical signs. While wild boar reached a humane endpoint earlier than domestic pigs did, the macroscopic lesions were comparatively less severe. In addition, wild boar had earlier viremia, and the virus was also detected earlier in tissues. The medial retropharyngeal lymph nodes were identified as key portals for ASFV infection in both subspecies. No viral genome was detected in nasal or rectal swabs until shortly before reaching the humane endpoint in both domestic pigs and wild boar, suggesting limited virus shedding in acute infections.

Re-domestication of feral pigs in Martinique: first results of growing-finishing trials to test meat consumption and consumers' perceptions.

In Martinique, pig production satisfies less than 20% of demand for pork, with traditional pig farming and wild pig hunting covering only a small proportion. This study has three parts: (i) for the first time, it analyses the performance of domesticated descendants of Creole feral pigs of Martinique based on a 29-day finishing test on two farms (A vs. B) with the same fibre-rich diet on a total of 40 pigs; (ii) it evaluates consumers' tastes based on a sensorial test by an untrained panel of 61 consumers who tasted pork prepared as a fricassee from either farm A or farm B; and (iii) evaluates willingness to pay (WTP) for Creole pork products and of the design of a future niche market. The average daily gain (ADG) of the finishing pigs was higher on farm A than on farm B (256 vs. 100 g/d, P < 0.001) resulting in a higher hot carcass weight on farm A than farm B (41.3 vs. 33.5 kg, P < 0.01), and better hot carcass yield on farm B than farm A (74.0 vs 68.8 %, P < 0.01). In the sensorial test, the consumers gave a higher score to the meat originating from the youngest pigs (Farm B), especially scores for tenderness and juiciness (+0.94 and +0.55 points, P < 0.05 and P=0.10, respectively). The 61 respondents were willing to pay more for processed products (sausage, pâté, ham) than for fresh meat. They considered that Creole pork has a better taste and is of better quality than industrial meats originating from mainstream genotypes. According to the majority of respondents, Creole pork should be rich in intra-muscular fat (100% of respondents) and low in inter-muscular fat (60% of respondents). Based on the survey, the main desirable future for Martinique's Creole pig production correspond to a low-carbon system with feed based on local resources, with on-farm slaughtering and short-distance sales (direct-to-consumer farm gate sale, sale at the butcher's or at the pig cooperative).

Novel anti-reflux ureteral skirt: proof of concept in a Yorkshire-Landrace pig model.

INTRODUCTION: Stents with anti-reflux properties have been previously described in various studies but not widely adopted. We designed, constructed and tested a novel umbrella-looking anti-reflux skirt on a double J stent at the level of the ureteral orifice in a previous ex-vivo study. This study serves as a proof of concept of testing this prototype in a porcine model. METHODS: 3 Yorkshire-Landrace pigs were put under general anaesthesia. Conventional bilateral retrograde stenting with white-colored double-J stents were performed. Deployment of anti-reflux skirt was performed unilaterally. Capsaicin mixed with methylene blue and saline were instilled in the bladder. Both stents were removed and methylene blue stain were inspected to assess the level of reflux. Bilateral stenting was performed again and stents/skirt prototype were left in-situ for 1 week. The procedure was repeated on Day 7 to re-test the anti-reflux property of the prototype after ureteral dilatation. RESULTS: Intraluminal reflux was evident, with methylene blue stain seen on the inner surface of the stents. Extraluminal reflux was proved with blue stain seen on the outer surface of the stents, both in undilated and dilated ureters. Study also proved the anti-reflux property of the skirt as the blue stain didn't go beyond the skirt, whereas the contralateral stent was stained up to proximal ureter. CONCLUSION: In this porcine in-vivo study, we elucidated that reflux occurred were both intraluminal and extraluminally. As a proof of concept, it also showed the anti-reflux property of a novel ureteral skirt.

Disseminated Sarcocystis miescheriana infection in a finisher pig in Grenada.

Sarcocystis miescheriana infection is an important cause of carcass condemnation during meat inspection. The infection can cause morbidity and mortality in domestic pigs. In this study, an 8-month-old finisher pig was presented to a local abattoir for slaughter. Multiple white nodular lesions affecting the meat were observed, resulting in the condemnation of the carcass. Consequently, half of the carcass was submitted to the necropsy diagnostic laboratory in the School of Veterinary Medicine for further evaluation. Grossly, all superficial and deep muscle groups had severe multifocal macrocysts (3 mm × 2 mm × 1 mm) on the surface and extending deep into the skeletal musculature. Histopathology revealed moderate multifocal granulomatous and eosinophilic myositis with intralesional degenerated and intact parasites. Sample genomic DNA sequence analysis of the 18S RNA gene showed 100% identity to S. miescheriana in the GenBank. This is the first report of S. miescheriana in Grenada, West Indies.

When and where? Day-night alterations in wild boar space use captured by a generalized additive mixed model.

Wild boar (Sus scrofa), an abundant species across Europe, is often subjected to management in agro-ecosystems in order to control population size, or to scare them away from agricultural fields to safeguard crop yields. Wild boar management can benefit from a better understanding on changes in its space use across the diel cycle (i.e., diel space use) in relation to variable hunting pressures or other factors. Here, we estimate wild boar diel space use in an agro-ecosystem in central Belgium during four consecutive "growing seasons" (i.e., April-September). To achieve this, we fit generalized additive mixed models (GAMMs) to camera trap data of wild boar aggregated over 1-h periods. Our results reveal that wild boar are predominantly nocturnal in all of the hunting management zones in Meerdaal, with activity peaks around sunrise and sunset. Hunting events in our study area tend to take place around sunrise and sunset, while non-lethal human activities occur during sunlight hours. Our GAMM reveals that wild boar use different areas throughout the diel cycle. During the day, wild boar utilized areas in the centre of the forest, possibly to avoid human activities during daytime. During the night, they foraged near (or in) agricultural fields. A post hoc comparison of space use maps of wild boar in Meerdaal revealed that their diurnal and nocturnal space use were uncorrelated. We did not find sufficient evidence to prove that wild boar spatiotemporally avoid hunters. Finally, our work reveals the potential of GAMMs to model variation in space across 24-h periods from camera trap data, an application that will be useful to address a range of ecological questions. However, to test the robustness of this approach we advise that it should be compared against telemetry-based methods to derive diel space use.

Microscopic detection and molecular characterization of Sarcocystis miescheriana in wild boars (Sus scrofa): first report from Greece.

The genus Sarcocystis includes protozoan parasites with an indirect life cycle. Sarcocystis spp. can infect various animal species and humans, causing sarcocystosis, a parasitosis of economic importance and zoonotic concern. Wild boars can act as intermediate hosts for Sarcocystis miescheriana and the zoonotic Sarcocystis suihominis that infects humans by consumption of raw or undercooked infected swine meat. In the present study, the diaphragmatic muscle tissue of 123 wild boars hunted in Greece was examined to determine the frequency of Sarcocystis spp. The samples were examined by tissue compression and molecular techniques. Under light microscopy, 34 out of 123 (27.6%) wild boars tested positive for Sarcocystis spp., while a higher infection prevalence (75%) was revealed by multiplex PCR performed in 100 of the samples. The partial mtDNA cox1 gene (~ 1100 bp) of 20 samples tested positive for S. miescheriana by multiplex PCR was amplified and sequenced. Sarcocystis miescheriana was identified as the only species involved in these infections. This is the first study on the prevalence of Sarcocystis spp. in wild animals in Greece. Further, large-scale surveys are needed to assess the prevalence and species of this parasite in Greece and to design efficient control and preventive measures in a One Health perspective.

First report of Echinococcus granulosus genotype 1 in a wild boar (Sus scrofa) from China.

Echinococcosis is a worldwide disease endemic to the western region of China. In 2023, echinococcosis was detected in one of 27 wild boars (Sus scrofa) in Yili Prefecture, Xinjiang, northwestern China. Histopathological staining and full sequence mitochondrial (mt) analysis were used to determine the infection genotype. Echinococcus granulosus was detected in the wild boar liver, and the cystic lesion characteristics indicated the E. granulosus genotype (G1). This case is the first confirmation of wild boar serving as a transmitter for the G1 genotype of E. granulosus within China. These findings suggest that surveillance is needed to assess the risk of E. granulosus sensu lato transmission to humans and wild animals.

An analysis of the social, cultural, and ecological factors that affect the implementation of biosecurity measures on smallholder commercial swine farms in Italy in the context of an emerging African Swine Fever outbreak.

African Swine Fever (ASF) is a contagious viral disease that infects wild and domesticated swine. In early 2022, the virus was found in wild boar in the Apennine mountains of mainland Italy.2 Since then, it has spread from wild boar to domesticated swine. To control the spread of ASF, an effective surveillance system and the implementation of strict biosecurity measures on farms are required yet are unevenly implemented across husbandry systems. Smallholder farms in particular are known to have low levels of biosecurity. In the Apennine mountains of Italy, small commercial farms have been found to have low levels of biosecurity despite being located in areas with high densities of wild boar, and, hence, being high-risk sites for potential ASF incursion and subsequent diffusion. To address the question as to why the level of biosecurity is low, interviews and participant observation were conducted with smallholder commercial farmers. The interviews identified the social, cultural, and ecological factors that affect the implementation of biosecurity measures in small commercial swine farms in the Apennines. Farmers expressed knowledge of priority biosecurity measures and an overall willingness to follow rules and regulations; however, the application of the measures in practice was uneven across farms. Economic, political, and ecological factors as well as farmer beliefs about biosecurity emerged as important factors affecting the implementation of biosecurity measures. These include economic constraints, challenges posed by the mountain environment, a shifting regulatory environment, and ideas about animal welfare. Other important factors include cultural factors such as the use of traditional agricultural methods and norms about customer access to animals, time constraints and the perceived hassle of implementing the measures, farmer age, farmer relationships with government officials and veterinarians, and the role of pigs in reducing farm waste. The study confirmed that wild boar are present in high numbers and in close proximity to smallholder commercial farms in the Apennines.

Improved stability and specificity of baits for oral administration of substances to wild boar.

Oral vaccination is one of the most effective interventions for disease control in wildlife. As a result of the recent global reemergence of African swine fever and ongoing classical swine fever and animal tuberculosis, oral vaccination of Eurasian wild boar (Sus scrofa) receives increased interest. Several baits for wild boar and feral pigs have been described, but developing more stable and personalized formulations is important. This paper proposes a new bait formulation primarily composed of corn flour, piglet feed, sugar, and honey as a binder to obtain improved elasticity. The bait consists of a matrix with no protective coats, has a hemispherical shape (ø 3.4 ×1.6 cm), and displays an anise aroma and blue color. The color and aroma did not affect bait choice by wild boar, while bait coloring contributed to avoid consumption by non-target species (corvids). Baits with the new formulation were significantly more resistant to humidity and high temperatures than previous versions. Simulations suggest that baits with the new formulation are elastic enough to resist impacts from a maximum altitude of 750 m. Thus, the new bait prototype solves several problems of previous bait formulations while keeping a format that can be selectively consumed by piglets and adult wild boar.

Pathogenic profile and antimicrobial resistance of Escherichia coli, Escherichia marmotae and Escherichia ruysiae detected from hunted wild boars in Sardinia (Italy).

The objective of this study was to evaluate the occurrence of E. coli in hunted wild boars in Sardinia (Italy) and to further characterize the isolates with Whole Genome Sequencing to assess the genetic relatedness and the presence of virulence and antimicrobial resistance (AMR) genes. Samples were taken from 66 wild boars between 2020 and 2022 slaughtered in five hunting houses. A total of 181 samples were tested, including 66 samples from mesenteric lymph nodes, 66 samples from colon content and 49 samples from carcass surface. Isolates referable to Escherichia species were detected in all of the wild boars sampled. On a selection of 61 isolates, sequencing was conducted and antimicrobial susceptibility was tested. Among these, three isolates were confirmed to be two Escherichia marmotae (cryptic clade V) and one Escherichia ruysiae (cryptic clade III). E. coli pathotypes identified were UPEC (13 %), ExPEC-UPEC (5.6 %) and ETEC (3.7 %). Moreover, 3/6 E. marmotae isolates had typical ExPEC genes. Genetic similarity was observed in isolates collected from animals slaughtered in the same hunting house; this suggests epidemiological links deriving from the presence of animals infected with closely related strains or the result of cross-contamination. Antimicrobial resistance genes were detected in three non-pathogenic E. coli isolates: one isolate had sul2, tet(B), aph(6)-ld and aph(3″)-lb resistance genes and two had the fosA7 gene. This study confirmed that wild boars can act as reservoirs and spreaders of pathogenic Escherichia species and it provides information for future comparative genomic analysis in wildlife. Although isolates showed a limited resistome, the detection of resistance in non-pathogenic isolates underlines the need to monitor antimicrobial resistance in the wild boar population. To the best of our knowledge, this is the first detection of E. mamotae and E. ruysiae isolates in wild boars in Italy and the presence of this pathogen in wildlife and livestock need to be investigated further.

Perfluoroalkyl substances in the meat of Polish farm animals and game - Occurrence, profiles and dietary intake.

Meat from farm animals (pigs, cattle and poultry) and game (wild boar and deer) was analysed in terms of thirteen perfluoroalkyl substances (PFASs). Wild boar muscle tissue was statistically significantly more contaminated than muscle tissue from other animals, and the species order of the lower-bound (LB) sum of four (∑4) PFAS (perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid, perfluorononanoic acid and perfluorohexanesulfonic acid) concentrations was wild boar > cattle > deer > pigs > poultry. None of the samples exceeded the maximum levels set by Commission Regulation (EU) 2023/915. Linear PFOS was the most frequently detected compound (in 21 % of all samples analysed and 100 % of wild boar samples), reaching its highest concentration of 1.87 µg/kg wet weight in wild boar. Dietary intake was estimated on the basis of the average per-serving consumption of pork, beef and poultry, and in the absence of such data for game, a 100 g portion was used for the calculation. Mean LB∑4 PFAS concentrations led to intakes between 0.000 and 1.75 ng/kg body weight (BW) for children and 0.000 and 0.91 ng/kg BW for adults. The potential risk to consumers was assessed in relation to the tolerable weekly intake (TWI) of 4.4 ng/kg BW established by the European Food Safety Authority in 2020. Exposure associated with the consumption of poultry, pork, beef and venison was negligible, being only <1 % of the TWI for children and adults; higher exposure was found to associate with the consumption of wild boar, being 63 % and 21 % of the TWI for children and adults, respectively. The findings of this research suggest that the intake of PFASs through the consumption of meat from Polish livestock and deer is unlikely to be a health concern. However, frequent consumption of wild boar meat could be a significant source of PFASs.