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Limited occurrence of Borrelia burgdorferi sensu lato in the European hedgehog (Erinaceus europaeus) and Ixodes hexagonus in Great Britain
No full textInterleukin 10 controls the balance between tolerance, pathogen elimination and immunopathology in birds
No full textEffective mucosal immunity in the intestine involves a fine balance between tolerance of the microbiome, recognition and elimination of pathogens, and inflammatory tissue injury. The anti-inflammatory cytokine IL10 regulates these processes in the intestines of mice and humans; the anti-inflammatory activity of IL10 is also conserved in birds. To determine the function of IL10 in avian mucosal immunity, we generated germ line modifications of the chicken IL10 locus to abolish or reduce IL10 expression. In vitro analysis of macrophage response to lipopolysaccharide confirmed the loss of IL10 protein expression, the lack of dosage compensation in heterozygotes, and prevention of autocrine inhibition of nitric oxide production in homozygous IL10 knockout macrophages. IL10-deficiency significantly altered the composition of the caecal microbiome, but unlike IL10-deficient mice and humans, IL10-deficient chickens did not exhibit spontaneous colitis. Following experimental challenge with Salmonella enterica serovar Typhimurium or Campylobacter jejuni in IL10-deficient chickens, enhanced clearance of the pathogens was associated with elevated transcription of proinflammatory genes and increased infiltration of inflammatory cells into gut mucosa. In IL10-deficient chickens challenged with the parasite Eimeria tenella, pathogen clearance was accelerated but caecal lesions were more severe and weight gain was compromised. Neither the heterozygous IL10 knockout nor a homozygous IL10 enhancer mutation had a major effect on pathogen clearance or inflammation in any of the challenge models. Our findings highlight the intrinsic compromise in mucosal immune response and have important implications for the development of strategies to combat avian and zoonotic pathogens in poultry
Polyhexamethylene Biguanide Nanoparticles Inhibit Biofilm Formation by Mastitis-Causing Staphylococcus aureus
No full textStaphylococcus aureus is a mastitis pathogen that compromises cow health and causes significant economic losses in the dairy industry. High antimicrobial resistance and biofilm formation by S. aureus limit the efficacy of conventional treatments. This study evaluated the potential of polyhexamethylene biguanide nanoparticles (PHMB NPs) against mastitis-causing S. aureus. PHMB NPs showed low toxicity to bovine mammary epithelial cells (MAC-T cells) at concentrations up to four times higher than the minimum inhibitory concentration (1 mu g/mL) against S. aureus. In Experiment 1, PHMB NPs significantly reduced biofilm formation by S. aureus by 50% at concentrations >= 1 mu g/mL, though they showed limited efficacy against preformed biofilms. In Experiment 2, using an excised teat model, PHMB NPs reduced S. aureus concentrations by 37.57% compared to conventional disinfectants (chlorhexidine gluconate, povidone-iodine, and sodium dichloroisocyanurate), though limited by short contact time. These findings highlight the potential of PHMB NPs for the control of S. aureus growth and biofilm formation
Cohort mapping review
No full textCohort research programmes follow individuals over time to enable study of effectsfrom various factors on health or other outcomes. To date, the global distribution offormal cohort programmes in cats and dogs has not been mapped, and a comprehensivesynthesis of their methodological characteristics is lacking. That limits methodsimprovement and wider adoption of cohort programmes in veterinary medicine. Amapping review methodology aligned with the JBI Manual for Evidence Synthesis wasused to summarise existing cohort research programmes on cats and dogs worldwide.Electronic databases were searched (Embase, MEDLINE, Scopus, Web of Science)to identify eligible cohort papers, followed by a two-step selection process (title andabstract screening, full text screening) for paper inclusion. Information extracted atthe individual cohort programme level covered: 1. location and veterinary specialty; 2.study design; 3. study variables; 4. collected data; 5. recruitment and retention strategies.Database searches yielded 6,777 unique papers, of which 73 met the inclusioncriteria. Twenty-two programmes were identified, predominantly in the UK (8/22, 36%)or US (6/22, 27%) with 55% (12/22) involving dogs. Most of the programmes (18/22,82%) aimed at disease prevention. Out of 19 programmes for which full-text paperswere available, and therefore more information could be extracted, animal demographicswere the most commonly considered study variable (15/19, 79%). The biggestreporting gaps were identified in the study planning phase, design, and programmemanagement. Consequently, limited information was retrievable from the programmespapers to create learning opportunities for other researchers planning future cohortprogrammes. Improved or new reporting practices are needed to enhance knowledgesharing and promote cohort programmes in veterinary medicine. The study protocolwas preregistered on the 27th of December 2023 (https://osf.io/wkg53/)
Attenuated but not virulent pseudorabies virus activates porcine bone marrow-derived dendritic cells
No full textPseudorabies viruses (PrV), the causative agent of Aujeszky's disease, continues to cause economic losses to pig producers across Southeast Asia. PrV is controlled by vaccination with live attenuated vaccines, such as the Bartha K61 strain, which has also shown promise as a viral vector. Despite the success of live attenuated PrV vaccines and their utility to be engineered as vaccine vectors, studies to understand the basis of their immunogenicity are scarce. Here, porcine bone marrow-derived dendritic cells (BMDC) were differentiated by culture with FLT3-L, generating eight myeloid cell populations differing in CADM1, CD172a, CD14, CD163 and CD11c expression, and included CADM1high conventional (c)DC and CD14+ DC. In vitro infection of BMDC with GFPexpressing PrV strains Bartha K61 and virulent Kaplan revealed a more rapid infection with Bartha K61. Compared to PrV Kaplan infection, there was also an increase in maturation marker expression (MHC class II and CD80/86) in both infected and bystander BMDC populations following Bartha K61 infection. This was accompanied by a concomitant increased cytokine response. IL-12 and TNF production associated with the cDC and CD14+ DC subsets, suggests that infection of these cells may be key to the potent immunogenicity associated with PrV Bartha K61 vaccination
Identification of Porrocaecum moraveci in red kites in England and Wales, a species of conservation concern
No full textWelfare of American mink, red and Arctic foxes, raccoon dog and chinchilla kept for fur production
No full textDeep-learning based morphological segmentation of canine diffuse large B-cell lymphoma
No full textDiffuse large B-cell lymphoma is the most common type of non-Hodgkin lymphoma (NHL) in humans, accounting for about 30–40% of NHL cases worldwide. Canine diffuse large B-cell lymphoma (cDLBCL) is the most common lymphoma subtype in dogs and demonstrates an aggressive biologic behaviour. For tissue biopsies, current confirmatory diagnostic approaches for enlarged lymph nodes rely on expert histopathological assessment, which is time-consuming and requires specialist expertise. Therefore, there is an urgent need to develop tools to support and improve veterinary diagnostic workflows. Advances in molecular and computational approaches have opened new avenues for morphological analysis. This study explores the use of convolutional neural networks (CNNs) to differentiate cDLBCL from non-neoplastic lymph nodes, specifically reactive lymphoid hyperplasia (RLH). Whole slide images (WSIs) of haematoxylin-eosin stained lymph node slides were digitised at 20 × magnification and pre-processed using a modified Aachen protocol. Extracted images were split at the patient level into training (60%), validation (30%), and testing (10%) datasets. Here, we introduce HawksheadNet, a novel lightweight CNN architecture for cancer image classification and highlight the critical role of stain normalisation in CNN training. Once fine-tuned, HawksheadNet demonstrated strong generalisation performance in differentiating cDLBCL from RLH, achieving an area under the receiver operating characteristic (AUROC) of up to 0.9691 using fine-tuned parameters on StainNet-normalised images, outperforming pre-trained CNNs such as EfficientNet (up to 0.9492), Inception (up to 0.9311), and MobileNet (up to 0.9498). Additionally, WSI segmentation was achieved by overlaying the tile-wise predictions onto the original slide, providing a visual representation of the diagnosis that closely aligned with pathologist interpretation. Overall, this study highlights the potential of CNNs in cancer image analysis, offering promising advancements for clinical pathology workflows, patient care, and prognostication
Identity disclosure and experience of discrimination of LGBT plus members of the veterinary professions in the UK: A mixed-method approach using survey data
No full textBackgroundWorkplace and educational discrimination remain institutional issues, particularly for minoritised individuals, and can negatively affect performance and opportunity. This study sought to investigate the experience of discrimination and identity disclosure (being 'out') of lesbian, gay, bisexual, transgender and others (LGBT+) members of the UK veterinary professions and students.MethodsA mixed-method approach was utilised to analyse 130 survey responses and examine associations between respondents' identity disclosure (being 'out' or not) and other variables. Reflexive thematic analysis was conducted, based within minority stress theory, to generate themes to explain findings.ResultsOver half the respondents reported having experienced or witnessed a range of discriminatory behaviours, and over half were not 'out' to all. When considering people's decisions around identity disclosure negative associations were detected for those who had witnessed discrimination and those who were unsure about antidiscrimination policy, and positive associations for those who felt supported at their place of work or study and by veterinary community in general. Three themes were generated that begin to explain respondents' experiences.LimitationsFurther research is required for institutions to know how our findings relate to their settings and to obtain additional in-depth understanding of individuals exposure to discrimination.ConclusionsOur findings indicate that LGBT+ discrimination remains an issue for some veterinary professionals and students in the UK. For the profession to move towards a more equitable future, we suggest that a multifaceted approach is needed to bolster institutional support and the active promotion of equality, diversity and inclusion initiatives