The microbiota of uterine biopsies, cytobrush and vaginal swabs at artificial insemination in Norwegian red cows

acceptedVersio

Nordic Vets against AMR—An Initiative to Share and Promote Good Practices in the Nordic–Baltic Region

In the Nordic countries, antimicrobial use in animals and the prevalence of antimicrobial resistance are among the lowest in Europe. The network “Nordic Vets Against AMR” organized a meeting in 2021, with key actors including representatives from universities, veterinary authorities and veterinary organizations in Finland, Norway and Sweden. This paper reflects the most important discussions on education, research, policy and future perspectives, including the experiences of these countries. It concludes that Nordic veterinarians are well placed to lead the way in the fight against antimicrobial resistance and that the sharing of experiences can support colleagues in other countries. Veterinary education must go hand in hand with research activities and continuously updated guidelines and legislation. There is also a need for postgraduate training on antimicrobial resistance and prudent antimicrobial use. The veterinary profession must, by any means necessary, protect the efficiency of antimicrobials for the sake of animal health, animal welfare and productivity, as well as public health. While restrictive use of antimicrobials is crucial, the ability of veterinarians to use this medical tool is also important for the sake of animal welfare and global food security

Nordic Vets against AMR—An Initiative to Share and Promote Good Practices in the Nordic–Baltic Region

Peer reviewe

Mikrobe-assosierte mønstre hos Aliivibrio salmonicida : roller i patogenesen ved kaldtvannsvibriose

Aliivibrio salmonicida is the cause of cold-water vibriosis, a hemorrhagic septicemia of farmed salmonids. Previous reports have shown that Al. salmonicida is able to circumvent defense systems of the fish host, and it has been suggested that the tissue damage observed in moribund fish is associated with the immune response raised towards the invading pathogen. This project was initiated to identify components of importance for virulence and immunogenicity, in order to increase the understanding of interactions between Al. salmonicida and its salmonid host. For microbial detection and induction of defense systems, the host immune system relies on microbe-associated molecular patterns (MAMPs), structures specific to microbes that serve as signatures for microbial presence. In this thesis, two well-known MAMPs have been investigated: flagellin of the flagellar motility apparatus, and lipopolysaccharide (LPS) of the outer membrane. In addition to their roles as targets for the immune system, both the flagellum and LPS serve important functions that aid bacterial survival. The results presented here demonstrate that neither flagellar motility nor LPS are required for invasion of salmon. However, both structures were shown to be involved in later stages of disease development. Results of challenge experiments demonstrated a function in virulence for the flagellar flagellins. Interestingly, bacteria cultured in implants within the peritoneal cavity of salmon showed an increase in production of flagellins, but not other components associated with motility. Combined, these results indicate a motility-independent requirement for flagellation in the cold-water vibriosis pathogenesis. However, the mechanisms involved remain unknown. In addition, the O-antigen moiety of LPS was shown to be essential for virulence. The results of this thesis indicate that O-antigen contributes to survival within the host and modulates the magnitude of the immune response raised in experimentally infected salmon. These observations may relate to the presence of LPS in VS-P1, an outer membrane complex that is shed from the bacterial surface and is hypothesized to decoy the immune response away from bacterial cells. While the findings of this thesis elucidate certain aspects of mechanisms involved in virulence in Al. salmonicida, new questions have also been raised. Knowledge about microbial pathogenesis is crucial for control of diseases, and this work may contribute to improvement of prophylactic strategies for cold-water vibriosis as well as other bacterial fish diseases

A unique role of flagellar function in Aliivibrio salmonicida pathogenicity not related to bacterial motility in aquatic environments

publishedVersio

Aliivibrio salmonicida requires O-antigen for virulence in Atlantic salmon (Salmo salar L.)

publishedVersio

Defining a metagenomic threshold for detecting low abundances of Providencia alcalifaciens in canine faecal samples

IntroductionAcute haemorrhagic diarrhoea syndrome (AHDS) in dogs is a condition of unknown aetiology. Providencia alcalifaciens is suspected to play a role in the disease as it was commonly found in dogs suffering from AHDS during a Norwegian outbreak in 2019. The role of this bacterium as a constituent of the canine gut microbiota is unknown, hence this study set out to investigate its occurrence in healthy dogs using metagenomics.Materials and methodsTo decrease the likelihood of false detection, we established a metagenomic threshold for P. alcalifaciens by spiking culture-negative stool samples with a range of bacterial dilutions and analysing these by qPCR and shotgun metagenomics. The detection limit for P. alcalifaciens was determined and used to establish a metagenomic threshold. The threshold was validated on naturally contaminated faecal samples with known cultivation status for P. alcalifaciens. Finally, the metagenomic threshold was used to determine the occurrence of P. alcalifaciens in shotgun metagenomic datasets from canine faecal samples (n=362) collected in the HUNT One Health project.ResultsThe metagenomic assay and qPCR had a detection limit of 1.1x103 CFU P. alcalifaciens per faecal sample, which corresponded to a Cq value of 31.4 and 569 unique k-mer counts by shotgun metagenomics. Applying this metagenomic threshold to 362 faecal metagenomic datasets from healthy dogs, P. alcalifaciens was found in only 1.1% (95% CI [0.0, 6.8]) of the samples, and then in low relative abundances (median: 0.04%; range: 0.00 to 0.81%). The sensitivity of the qPCR and shotgun metagenomics assay was low, as only 40% of culture-positive samples were also positive by qPCR and metagenomics.DiscussionUsing our detection limit, the occurrence of P. alcalifaciens in faecal samples from healthy dogs was low. Given the low sensitivity of the metagenomic assay, these results do not rule out a significantly higher occurrence of this bacterium at a lower abundance

DataSheet_1_Defining a metagenomic threshold for detecting low abundances of Providencia alcalifaciens in canine faecal samples.docx

IntroductionAcute haemorrhagic diarrhoea syndrome (AHDS) in dogs is a condition of unknown aetiology. Providencia alcalifaciens is suspected to play a role in the disease as it was commonly found in dogs suffering from AHDS during a Norwegian outbreak in 2019. The role of this bacterium as a constituent of the canine gut microbiota is unknown, hence this study set out to investigate its occurrence in healthy dogs using metagenomics.Materials and methodsTo decrease the likelihood of false detection, we established a metagenomic threshold for P. alcalifaciens by spiking culture-negative stool samples with a range of bacterial dilutions and analysing these by qPCR and shotgun metagenomics. The detection limit for P. alcalifaciens was determined and used to establish a metagenomic threshold. The threshold was validated on naturally contaminated faecal samples with known cultivation status for P. alcalifaciens. Finally, the metagenomic threshold was used to determine the occurrence of P. alcalifaciens in shotgun metagenomic datasets from canine faecal samples (n=362) collected in the HUNT One Health project.ResultsThe metagenomic assay and qPCR had a detection limit of 1.1x103 CFU P. alcalifaciens per faecal sample, which corresponded to a Cq value of 31.4 and 569 unique k-mer counts by shotgun metagenomics. Applying this metagenomic threshold to 362 faecal metagenomic datasets from healthy dogs, P. alcalifaciens was found in only 1.1% (95% CI [0.0, 6.8]) of the samples, and then in low relative abundances (median: 0.04%; range: 0.00 to 0.81%). The sensitivity of the qPCR and shotgun metagenomics assay was low, as only 40% of culture-positive samples were also positive by qPCR and metagenomics.DiscussionUsing our detection limit, the occurrence of P. alcalifaciens in faecal samples from healthy dogs was low. Given the low sensitivity of the metagenomic assay, these results do not rule out a significantly higher occurrence of this bacterium at a lower abundance.</p