Irish Veterinary Journal最新文献

Accurate diagnosis of Bovine Tuberculosis (bTB) in cattle is important for success of eradication programmes, but the current reliance on the single intradermal comparative cervical tuberculin (SICCT) test is not achieving disease eradication in all jurisdictions, including Northern Ireland (NI). In this study, a novel Phagomagnetic separation (PhMS)-qPCR assay to rapidly detect viable Mycobacterium bovis in bovine blood samples was evaluated. A total of 149 heart blood samples were collected from cattle at exsanguination point of the slaughter line at a NI abattoir between June and August 2023 - 74 from TB reactor cattle (compulsorily culled within days of a positive SICCT test result) and 75 from routine slaughter cattle (< 30 months). Peripheral blood mononuclear cells (PBMCs) were isolated and lysed to release any mycobacteria present before PhMS-qPCR and culture were performed to detect presence of viable M. bovis. The DNAs obtained were subsequently tested for evidence of viable Mycobacterium avium subsp. paratuberculosis (MAP) also. PhMS-qPCR results indicate that of the TB reactor cattle with conclusive PhMS-qPCR results, 7.5% of bloods tested positive for viable M. bovis only, 41.8% for viable MAP only and 28.4% showed evidence of co-infection (both M. bovis and MAP detected). Of the routine slaughter cattle with conclusive PhMS-qPCR results, 22.4% of bloods tested positive for viable M. bovis only, 19.4% for viable MAP only and 20.9% showed evidence of co-infection. Of the blood samples with conclusive culture results, 19.6% TB reactors and 25.4% routine slaughter cattle were M. bovis culture positive. No agreement was observed between the M. bovis PhMS-qPCR assay and M. bovis culture results (Kappa - 0.028, 95% CI -0.162 to 0.105). Results of this study provide proof-of-concept that the PhMS-qPCR assay is able to detect viable M. bovis in bovine blood, although a different qPCR assay with greater detection sensitivity will need to be identified going forward. A surprisingly high number of M. bovis/MAP co-infections were detected in the blood of NI cattle, which may be contributing to failure of the bTB eradication scheme. The latter warrants further investigation.

Background: Since the abolition of EU milk quotas in 2015, the Irish dairy industry has expanded with a 16.6% increase in calf births since 2011. Calf losses have major implications for the economic viability and sustainability of dairy enterprises. There is a paucity of literature on mortality in calves from birth to six months, particularly at a national herd level. Previous studies have tended to focus on herd size as a risk factor for calf mortality rather than the possible influence of herd expansion. The purpose of this study is to quantify any association between dairy herd expansion and the risk of being classified as a high or low calf mortality herd based on analysis of national dairy herd identification and movement records in Ireland from 2016-2020.

Results: In calves aged under 6 months, herds that expanded > 20% (OR 1.23 95% CI: 1.10-1.37, p < 0.001) and > 45% (OR 1.22, 95% CI:1.09-1.36, p = 0.001), were more likely to have > 10% herd calf mortality, compared to herds that did not increase in size. Newly established herds were more likely to have poor mortality outcomes (OR 2.44, 95% CI: 1.82-3.29, p < 0.001) compared to herds that did not increase in size. Herd expansion < 20% was not associated with mortality outcome. Herd ordinal location and herd size were significant risk factors for > 10% herd calf mortality.

Conclusion: This study has demonstrated that herds that have expanded > 20% over five years and newly established herds were more likely to have poor mortality outcomes. It suggests that new entrants into dairy farming may benefit from targeted emphasis on herd health management. The results also highlight the value of national data as a tool to determine optimisation of farm interventions and surveillance and policy decisions to prioritise animal health and welfare.

Background: Ovine lameness represents a significant production and welfare challenge to farmers and comprises two main categories, infectious and non-infectious lameness. The leading infectious lameness conditions are interdigital dermatitis (ID), footrot (FR) and contagious ovine digital dermatitis (CODD). The predominant types of non-infectious foot conditions include toe granulomas (TG) and shelly hoof (white line disease; SH). There is a paucity of information available as to how Irish farmers treat infectious foot lesions in sheep. This study aimed to i) Establish farmer-reported prevalence of lameness in Irish sheep flocks, ii) Assess farmers' ability to identify infectious and non-infectious lameness types, iii) Examine the treatment methods employed by farmers for managing and treating infectious lameness in sheep.

Results: The survey was conducted opportunistically and non-randomly. Three hundred and sixty-three valid responses were gathered. The median overall farm lameness prevalence reported was 6.0% (IQR: 4.0%-10.0%). Respondents reported ID as the most common lameness condition with a median estimated prevalence of 10.0% (IQR: 4.0 - 15.0). Respondents identified 77.9%, 76.6%, 61.7%, 67.3% and 67.0% of ID, FR, CODD, TG and SH lesions correctly, respectively. Where the respective lesion was correctly identified 95.1%, 90.2%, 49.2%, 59.7% and 68.4% reported to have seen ID, FR, CODD, TG and SH lesions, respectively on their farm previously. Antibiotic aerosol was the most frequently utilised treatment for ID (71.3% [95% CI:65.2, 76.8%]) reported by survey respondents. Antibiotic injection was reported by respondents as the most used treatment for FR (72.2% [95% CI: 65.8,78.0%]) and CODD (85.1% [95% CI: 75.8, 91.8%]). Therapeutic foot trimming was practiced by 52.9% (95% CI:46.1,59.6%) of respondents for the treatment of FR.

Conclusions: Interdigital dermatitis (ID) posed the greatest burden to Irish farmers, with a median farm prevalence of 10.0%, while footrot affected 90.2% of flocks (median 4.0%). Contagious ovine digital dermatitis, previously considered rare, was reported in 47% of flocks (median 3%). Farmers' ability to correctly identify lesions varied from 79.9% for ID to 62.4% for CODD. Therapeutic foot-trimming, remain widely used within Irish flocks and was reported by 52.9% of respondents for the treatment of FR.

Background: Next-generation sequencing of canine spontaneous cancer is a powerful approach in both comparative oncology and veterinary genomics. We encountered a unique case with concurrent mammary tumors. Using whole-genome sequencing (WGS), we profiled the tumor-specific landscape of somatic mutations across multiple tumor subtypes, providing unprecedented evidence within an identical genetic background.

Results: Of the seven mammary gland tumors (MGTs) isolated, two were diagnosed as benign and five as malignant. High-quality WGS (34.5X average sequencing depth, ≥ 20X coverage across 94.9% of the genome) on tumors and a blood sample revealed missense mutations in human breast cancer-related genes such as BRCA2 and TP53. Furthermore, we found evidence of canine-specific somatic mutations depending on the tumor subtypes, including HECTD4 in malignant tumors and NIPBL in epithelial-derived malignant tumors.

Conclusions: This unique case study provides novel insights into the genomic heterogeneity, clonal evolution, and subtype-specific pathogenesis of naturally occurring canine MGTs. Despite some inherent limitations and potential for individual-specific variation, our results emphasize and guide future large-scale, longitudinal studies to further elucidate the clinical and biological significance of key somatic alterations.

Chlamydia spp. are a group of gram-negative, obligate intracellular bacteria that represent significant pathogens causing chlamydiosis in both animals and humans. Avian chlamydiosis (AC), primarily caused by Chlamydia psittaci, C. avium, C. gallinacea, and C. ibidis, has been documented in over 460 avian species. Qinghai Lake, China's largest saltwater lake and a critical overwintering site for migratory birds, served as the study area to investigate Chlamydia prevalence in wild birds. Fecal samples from 125 birds revealed an overall Chlamydia spp. infection rate of 28.8% (36/125), with three species identified: C. abortus (55.6%, 20/36), C. avium (44.4%, 16/36), and C. psittaci (13.9%, 5/36). Phylogenetic analysis through amplification of the 16 S rRNA (5 samples), IGS-23 S rRNA (6 samples), and ompA (5 samples) genes revealed that all sequences obtained in this study were assigned to the Chlamydiaceae family. The ompA sequence of C. abortus obtained in this study clustered closely with the reference strain GN6 (CP021996.1) isolated from aborted yak fetuses (Bos grunniens), a bovid species typically domesticated and endemic to the Qinghai-Tibet Plateau, showing 100% sequence identity. In contrast, C. avium ompA sequences shared 87.40% identity with the reference strain 10DC88. The identical genomic profile of C. abortus between wild birds and domesticated yaks suggests potential cross-species transmission in the Qinghai-Tibetan Plateau, where overlapping habitats of wildlife and livestock may facilitate pathogen exchange. These findings underscore the zoonotic risks posed by Chlamydia species circulating in this ecologically critical region, with implications for the health of local livestock (yaks, Tibetan sheep), human populations, and migratory bird conservation.

Bovine Viral Diarrhoea Virus (BVDV), Border Disease Virus (BDV), and Bovine Herpesvirus-1 (BoHV-1, the cause of Infectious Bovine Rhinotracheitis, IBR), are economically important endemic viruses in ruminant livestock in the United Kingdom and Ireland. Deer could undermine control efforts in livestock by contributing to virus transmission and maintenance, but information on the presence of these viruses in the wild deer population is lacking. Blood samples from wild fallow and sika deer culled in Northern Ireland were collected opportunistically in the 2022-23 hunting season and tested using enzyme-linked immunosorbent assay (ELISA) for the presence of antibodies to these viruses (n = 116). No antibodies against BoHV-1 were detected. Antibodies against pestivirus were detected in three samples (2.6%), all from sika deer, and constitute the first report in this species in Europe. Virus strain differentiation by virus neutralization test (VNT) was inconclusive. Results therefore indicate no evidence of exposure to BoHV-1 and very low levels of pestivirus exposure in these deer populations. Based on these results there are currently no grounds to implicate deer as significant wildlife reservoirs of these viruses.

Transient myocardial thickening (TMT) is characterised by reversible left ventricular myocardial thickening. A 2-year-old castrated male British Shorthair was presented with a history of severe vomiting for 2 days. Based on abdominal radiography and ultrasonography, the cat was diagnosed with an obstructive gastrointestinal foreign body. Preoperative echocardiography revealed an increased maximum left ventricular wall thickness (LVWT: 6.9 mm, measured at end-diastole) and ratio of the left atrium to the aortic root (LA/Ao: 2.1), indicative of a hypertrophic cardiomyopathy phenotype. An enterotomy was performed, and the foreign body was found to be an almond. Immediately after surgery, the cat became tachypnoeic, and thoracic radiography revealed pulmonary oedema. The cat was then treated with cardiac medications. Five days after surgery, the cat's condition clinically normalised. Two months after the first presentation, repeated echocardiography revealed a decreased LVWT (4.8 mm) and LA/Ao (1.58). The cat was diagnosed with TMT, and all cardiac medications were discontinued. The cat remained clinically well for 14 months after the last presentation. This is the first case report to demonstrate that foreign body ingestion may cause TMT, and that congestive heart failure (CHF) can develop after enterotomy in cats with subclinical TMT. The possibility of TMT should be considered in cats with foreign body ingestion that requires anaesthesia and/or surgery because it may trigger CHF, which could ultimately lead to death.

Veterinary education has long relied on lecture-based methods and conventional case-based learning, approaches that may not fully cultivate the critical and systems thinking skills required in today's complex clinical environment. In response, we developed an innovative digital tool that integrates interactive gaming, narrative-driven expression, and structured debriefing into a cohesive simulation framework. Using backyard poultry management-a case selected for its regulatory and ethical complexities in European practice-as our testbed, the simulation engages students through a point-and-click game focused on laying hens. The tool presents a series of interactive decision points and intentional "traps" that prompt reflective discussion during post-game debriefing sessions.A qualitative approach was employed to analyze data collected from focus group discussions, written group documents, and facilitator reflections during simulation sessions with veterinary students. Our thematic analysis identified three primary themes: (1) a multifactorial understanding of poultry health, (2) diverse perceptions of the veterinarian's role in managing complex challenges, and (3) the simulation as an effective reflective trigger for enhancing clinical reasoning. These findings indicate that the simulation not only promotes active learning and systems thinking but also bridges the gap between theoretical knowledge and real-world clinical decision-making by linking clinical observations with broader regulatory, economic, and social considerations.Despite limitations such as reliance on self-reported data and the absence of a control group, our study demonstrates that a facilitation-driven simulation framework can transform case-based learning into a dynamic, reflective inquiry process. This approach offers a promising alternative for enhancing educational outcomes in veterinary education and lays the groundwork for future research incorporating objective measures of competence and further refinements to balance structured guidance with learner autonomy.