Danish Agriculture and Food Council

The epidemiology of swine influenza A virus (swIAV) has undergone a change from causing mainly epidemic infections to continuous endemic circulation within herds. Several studies have traced the within-herd swIAV transmission pattern. However, studies with more frequent samplings of targeted age groups are needed to increase the current understanding of virus transmission dynamics. In addition, data on the efficacy of different intervention methods for reducing swIAV spread are highly relevant for disrupting endemic swIAV infections. Therefore, this study aimed to investigate the weekly influenza infection dynamics and evaluate subsequent interventions, including vaccination and management changes. Two batches of pigs in two sow herds (Herd 1 and 2) were sampled with nasal swabs and blood samples from one week of age to the end of the nursery period. In each batch, ten sows were included with each six piglets including three cross-fostered and three of the sows own piglets. Nasal swabs were tested for the presence of swIAV, and blood samples were tested for swIAV antibodies using ELISA and HI-test. In Herd 2, interventions including pre-farrowing vaccination, limited cross-fostering, litter-wise weaning and disinfection of tools and hands were implemented during a second round of sampling in two batches as described above. In both herds, an endemic presence of swIAV was observed, with Herd 1 having one circulating swIAV subtype (H1C.2.4N2G) circulating in the farrowing unit and Herd 2 having two swIAV strains (H1C.2.4N2G and H1N1pdm09) circulating both before and after weaning. Maternally derived swIAV antibodies were successfully transferred from sow to piglets, but despite high levels, swIAV infections was observed in the piglets down to one week of age and a lack of subsequent seroconversion was observed. The implementation of pre-farrowing vaccination increased the level of swIAV antibodies in sows and piglets but had no obvious effect on viral shedding and clinical disease. The endemic state of swIAV infections in sow herds was clearly illustrated in this study along with the difficulties in controlling swIAV through vaccinations and management changes in an environment that favours virus circulation.

Abstract The study of stranded animals is a valuable aid to monitoring marine mammals globally. However, the utility of strandings data depends on their quality and representativeness, which is affected by various biological, physical, social and economic factors. An analysis of how stranding networks work could help understand limitations in the data collected and facilitate correcting for or even eliminating them. In 2021, the International Council for the Exploration of the Sea’s Working Group on Marine Mammal Ecology carried out an expert consultation using a questionnaire to provide insight into the contribution of European stranding networks as a monitoring tool in European countries with Northeast Atlantic and adjacent coasts (hence also including some networks operating along the Mediterranean coast). A key aim was to identify ways to improve data on mortality of marine mammals due to fishery bycatch. The present paper is the first of a two-part series based on the responses to the questionnaire by 45 organisations from 19 countries, and focuses on characterising the activities and capacities of the stranding networks surveyed, identifying differences within and between countries, highlighting strengths and weaknesses, and providing recommendations to enhance the value and credibility of the information collected. The second paper will focus on the information specifically related to mortality due to fishery bycatch. Stranding networks provide extensive spatio-temporal coverage of European coastlines, but their activities may be constrained by limited resources as well as limitations imposed by the stranding process. There is a need for better coordination and standardisation of the collection and analysis of data and samples and increased spatial coverage to fill gaps. To improve data quality, in particular to support assessment of impacts of threats such as bycatch, more necropsies and associated sample analysis are needed. It would also be advantageous to collect more information from less fresh animals, record search effort, and give greater attention to pinnipeds and non-marine mammal taxa. We also highlight the need to make information available and the potential value of a common database. Streamlining the reporting of results at the European level and providing systematic funding to stranding networks in accordance with their needs are necessary steps to optimise their role as a tool for the long-term monitoring of marine mammals and other marine megafauna in Europe.

Outdoor pig production systems can increase exposure to helminth infections such as Ascaris suum. Anthelmintic drug treatments are currently the primary strategy for controlling such infections; however, this approach is considered unsustainable due to the risk of parasites developing anthelmintic resistance. This study investigated the potential anthelmintic effect of a 2% w/w fermented rapeseed–seaweed (FRS) dietary supplement administered over an 11–12 week period in growing-finisher pigs. Outcomes assessed included parasitic fecal egg counts (FEC), serology, gut microbiota composition, and systemic inflammation. The FRS supplement consisted of 6% Saccharina latissima, 6% Ascophyllum nodosum, and 88% rapeseed meal (based on dry matter) and was provided in two different batches. Supplementation with FRS tended to lower FEC and reduce the incidence of A. suum infection. However, this effect varied between batches. FRS also influenced gut microbiota composition: pigs that were fed the second batch of FRS showed an increased relative abundance of several Bacteroidetes members (e.g., Prevotella), while unsupplemented pigs were enriched with various taxa from the Firmicutes phylum, such as Clostridium spp. Furthermore, pigs fed the second batch of FTR showed reduced daily weight gain compared to those fed the control diet. Overall, our results indicate that FRS modulates the gut microbiota toward a composition potentially associated with improved gut health and may have promise as a prebiotic or novel feed additive to help reduce helminth infections.

Incursions and persistence of high pathogenicity avian influenza viruses (HPAIVs) in Europe have resulted in devastating epidemiological seasons in 2020/2021 and 2021/2022 compared to previous seasons. HPAIVs were confirmed in 27 outbreaks in poultry and other captive birds, and in 553 wild birds throughout Denmark. Our data revealed that the viruses detected in Denmark were highly similar to contemporary HPAIVs in other European countries in both seasons. The HPAIVs detected in Denmark belonged to clade 2.3.4.4b and were of different subtypes (H5N1, H5N3, H5N5, and H5N8). Several viruses identified in 2021/2022 were found to be highly similar to those found in the previous season, whereas others were identified as novel viruses. The genetic data combined with epidemiological information on the outbreaks in Denmark were used to explore the most likely route of introduction into each infected poultry production site. In a few cases, the data supported that the outbreaks were caused by between-farm HPAIV transmission. However, the majority of outbreaks in poultry are believed to have been a result of direct or indirect contact with HPAIV-infected wild birds. With a logistic regression model, it was determined that the only significant risk factor for experiencing an outbreak was the poultry production type. Turkey and mallard farms had a significantly higher risk of experiencing an outbreak in comparison to chicken farms. These findings prompt reconsideration of AIV preventative measures limiting HPAIV outbreaks, not only at the wild bird-poultry interface but also due to secondary transmissions between poultry farms.

According to the EU legislation, bovines subjected to emergency slaughter must undergo a physical ante-mortem inspection (AMI) on the farm before slaughter if the meat is to be placed on the market for human consumption. This pilot study examined the performance of online AMI using a software system that enabled a video consultation between the veterinarian and the farmer. During 2022-2023, 38 bovines, possibly eligible for emergency slaughter, were included in the study. A comparison between online and physical AMI was carried out. Furthermore, a comparison was made between two different veterinarians (vet.1 and vet.2) about the performance of AMI for each bovine. The results showed that vet.1 considered the online judgement as adequate for 95% of the cases in the study, whereas vet.2 considered 90% adequate. Moreover, the agreement between the two veterinarians was high (accuracy = 90%), both regarding the adequacy of the system and the eligibility of the bovine for slaughter. Prerequisites for using online AMI are suitable video equipment, a reliable internet connection and sufficient light. Furthermore, the use of a checklist will help to assure standardized online AMI. Saving the recorded videos will reduce the risk of fraud and enable training and calibration of veterinarians. In conclusion, online AMI of bovines destined for emergency slaughter will, in most cases, be comparable to physical AMI on-farm. However, the use of online AMI presupposes a change of the EU legislation.

The aim of this study was to investigate the effect of avoiding flock treatment on resistance levels in the intestine of pigs. To investigate this, studies, each in two pig herds, quantified resistant coliforms by culture method in pigs treated as flock or as individual animal treatments orally with neomycin against post-weaning diarrhea (PWD) or intramuscularly with amoxicillin to prevent umbilical infection. Individual oral treatment against PWD did not lead to a lower number or proportion of resistant coliforms compared to flock treated pigs in any of the two herds under study, despite reduction of treatment incidences to 32% and 35% of pigs. After intramuscular treatment against umbilical infection, fewer resistant bacteria were seen in individually treated piglets in a herd with low treatment incidence (33%), while no reduction of resistant coliform bacteria compared to flock treatment was observed in the other herd with higher treatment incidence (86%). Thus, individual animal treatment reduced the amount of antimicrobial used, but concurrent reduction in resistant coliform bacteria was not always observed.

Recent publications in the field of food authentication have reported using analytical methods which measure changes in sample composition. These changes can be due to a variety of causes such as the presence of adulterants, different production methods, or varying geographical origins of food. While the increasing use of marker-based approaches is beneficial in combating food fraud, there is a pressing need to adopt a harmonized approach for validating these markers. In this article, we make recommendations for harmonized terminologies and general definitions related to food authenticity markers. First, we propose the terms “primary” and “secondary” markers to distinguish between direct and indirect authentication. The terms “single” and “dual” authenticity markers, and authentic “profiles” and “fingerprints” are suggested to distinguish between the number of analytical targets used. We also recommend that the terms: “threshold”, “binary”, and “interval” markers are applied depending on how they discriminate authentic from non-authentic samples. Second, we advocate for harmonization in marker discovery approaches. A summary of the main analytical techniques, published guidelines, data repositories, and data analysis approaches is presented for various marker classes while also stating their applicability and limitations. Finally, we propose guidelines for the analytical community concerning marker validation. In our view, the validation of the authentication method should include the following steps: 1) applicability statement; 2) experimental design; 3) marker selection and analysis; 4) analytical method validation; 5) method release; 6) method monitoring. Implementing these approaches will represent a significant step towards establishing a wide range of fully validated and accredited methodologies that can be applied effectively in food authenticity monitoring and control programs.

Chicken eggs can be a significant source of human PFAS exposure. A survey of PFAS in commercial eggs from larger farms across Denmark showed the absence or low contents of PFAS in free-range and barn eggs. However, organic eggs from eight farms collected in September 2022 had a similar profile of nine PFASs with a predominance of odd over even carbon length PFCAs. Farm 11–13 e.g. had egg yolk ng/g concentrations of PFOA 0.07 ± 0.02; PFNA 0.37 ± 0.04; PFDA 0.13 ± 0.00; PFUnDA 0.22 ± 0.04; PFDoDA 0.06 ± 0.02; PFTrDA 0.15 ± 0.04; PFTeDA 0.02 ± 0.02; PFHxS 0.10 ± 0.04; PFOS 2.62 ± 0.11. Normalised to PFOS, the relative sum of other PFAS showed no difference between the eight organic egg samples, but significant differences between mean individual PFASs (p = 1.4E-25), reflecting a similar profile. The PFAS found in two fishmeal samples with the same origin as the fishmeal used for the organic feed production, could account for the contents in the eggs via estimated transfer from the feed. Furthermore, the estimated transfer from concentration in feed to concentration in egg increased with the carbon length of the PFCA. Exposure (95th percentile) of ∑4PFAS (PFOA, PFNA, PFHxS, PFOS) solely from consumption of 311 g ∼ 5–6 organic eggs/week was for children 4–9 years 10.4 ng/kg bw, i.e. a significant exceedance of the tolerable weekly intake of 4.4 ng/kg bw established by the European Food Safety Authority. Based on the PFAS exposures from organic egg consumption, the organic egg producers decided voluntarily to cease adding fishmeal to the feed. Since the feed-to-egg half-lives are ≤1 week for PFOA, PFOS, and PFHxS, the removal of fishmeal as a feed ingredient should eliminate PFAS after 1–2 months. This was demonstrated in analyses of ten organic egg samples collected by the authorities without PFAS in eight and with 0.1 and 0.4 ng/g ∑4PFAS in two samples.

In the European Union, bacteriological examination (BE) can be used as a decision support tool for an individual slaughter animal, if a clear decision regarding fitness for human consumption cannot be reached after performing the post-mortem meat inspection at the abattoir. The mandatory use of BE started already in the beginning of 20th century and the methods have since evolved in the different countries using it. Although still in use, discussions have taken place on whether BE is still a useful part of meat inspection. Currently, there is no European consensus regarding how to set up the methods or how to interpret the results Still, there is a need to avoid unnecessary food waste, while at the same time guaranteeing food safety. In this descriptive study, we mapped the BE methods currently used in five European countries, namely Denmark, Finland, Germany, Italy and the Netherlands. The results show there is considerable variation between the countries regarding the specific analyses, sample matrices and media used. There is also variation in the indications when BE should be performed as well as when the results lead to condemnation. Although the results will be interpreted together with the pathological findings in the carcass, clearly written instructions should be available on how to interpret the results and when to perform condemnation. BE is used more often for cattle than for pigs, and e.g., in Denmark, BE is not used for pigs due to costs. Although BE can still be used to detect animals with a generalised infection at the time of slaughter, other methods that would be easier to standardise and accredit should be developed.