Preventive Veterinary Medicine

Bovine respiratory disease (BRD) is the most common cause of morbidity and mortality in cattle. The effects of BRD are most marked during the first weeks after arrival in calf-rearing units. Vaccination is a tool that can help to control the disease by reducing both the incidence itself and the massive use of antibiotics. Recently, a new multivalent vaccine (DIVENCE(R)), containing live gE/tk double-gene deleted BoHV-1, live-attenuated BRSV, inactivated PI3, BVDV-1 recombinant protein and BVDV-2 recombinant protein, has been designed to protect cattle against the main viral pathogens associated with BRD. The aim of this study was to demonstrate the efficacy of DIVENCE(R) against BRD in field conditions. A total of 360 animals from three different batches were included in the study: one batch of 108 Holstein-Friesian males (Farm 1), another batch of 99 Holstein-Friesian males (Farm 2), and 153 Belgian-Blue cross males and females (Farm 3). On each feedlot, a single batch of animals was included in the study, with a mean age of approx. ten weeks (73.4{+/-}0.6 days). On the vaccination day (Day 0 of the study; D0), calves from the same batch were randomly distributed between the two study groups. The vaccinated group (n=183) received the DIVENCE(R) vaccine and the control group (n=177) received a placebo injection of phosphate-buffered saline (PBS) solution. Both groups were given two intramuscular doses (2 mL/dose) of the corresponding product three weeks apart. All animals were monitored during the entire fattening period (approx. 9 months) after vaccination to assess the incidence, severity, and morbidity of BRD as well as administered treatments and feed performance. Overall, vaccinated animals had significantly (p<0.004) lower morbidity than controls, with only 49 out of the 183 vaccinated calves (26.78%) presenting at least one episode of respiratory disease (RD), versus 73 out of the 177 control calves (41.24%). Thus, a reduction of 35.1% in morbidity was observed in the vaccinated animals. In terms of RD cases, vaccinated animals had a significantly (p<0.001) lower number of cases than control animals, with only 66 cases reported in the 183 vaccinated calves (0.36 cases/calf) versus 110 cases in the 177 control calves (0.62 cases/calf). A reduction of 42% in cases was observed in the vaccinated animals. During the study follow-up, a BRSV outbreak was reported in one of the farms (Farm 1) on Day 23, just two days after the second dose. The vaccinated group had significantly (p<0.02) lower morbidity (11 animals out of 54; 20.4%) and severity (score of 1.70) compared to the control group (29 animals out of 54; 53.70% and score of 2.11). Overall, vaccinated animals needed significantly (p=0.01) fewer antimicrobial treatments (at least one due to RD) than controls. Furthermore, vaccinated animals presented numerically higher average daily weight gain (p=0.07) and significantly higher carcass weight (p=0.01) than controls, at 35.78 g/day and 6.58 kg, respectively. Vaccination with DIVENCE(R) at the beginning of the fattening period decreased the incidence and morbidity of BRD following a BRSV outbreak only two days after the primary vaccination scheme. Additionally, the incidence and morbidity of BRD throughout the entire fattening period was reduced in the vaccinated animals. Thus, DIVENCE(R) can improve economic outcomes in fattening units by reducing antibiotic treatments and enhancing performance.

Structured SummaryO_ST_ABSObjectivesC_ST_ABSTo examine the prevalence and types of work-related injuries in companion animal practices, explore the context of their occurrence, and the behaviours of injured persons. MethodsA mixed-methods analysis of a cross-sectional online survey of UK employees of a consolidated group of veterinary practices. ResultsOf 647 respondents, 77.6% experienced a work-related injury during their career. In the previous year, 60.2% of veterinary nurses and 58.3% of veterinarians were injured, most frequently in consultation rooms, prep areas, kennels, and reception. Animal-related injuries were the most prevalent injury type. Injuries frequently occurred during cat restraint, anaesthetic recovery, and clinical examinations. Needlestick injuries made up 15.8% of veterinary injuries. 16.3% of injured nurses and 19.4% of injured vets attended hospital. 34.3% of nurses, and 25.1% of vets, needed more than a week to recover from their injuries. Fewer than 10% took time off work, often due to a sense of duty, the ability to manage a reduced workload, or simply wanting to "get on with it." Most injuries to vets went unreported, due to perceived time pressures or the belief that the injury was minor. Around half adjusted their behaviour post-injury, becoming more cautious or changing handling techniques. Clinical significanceThis study reveals a high rate of work-related injuries in companion animal practices. A culture of presenteeism and blame often downplays these risks, hindering safety. To reduce injuries, a shift towards shared responsibility and reflective learning is needed, driven by strong leadership and open communication.

IntroductionOccupational injuries are prevalent within the veterinary sector, though their true extent is unknown as evidence indicates widespread under-reporting of injuries. This study aimed to: assess injury under-reporting across roles in UK veterinary practices; and audit the type, frequency, and outcomes of workplace injuries within a large veterinary organisation. MethodsA retrospective audit was conducted on a large veterinary organisations accident reporting system in 2022. Under-reporting was estimated using a modified capture-recapture method, comparing audit records with self-reported injury data from a cross-sectional staff survey stratified by role and employment figures. Audit data were descriptively analysed and compared with survey data. ResultsThe overall injury under-reporting rate was 68.9%; for every 100 workplaces injuries, 69 went un-reported. Levels of under-reporting were higher in companion animal practices (70.0%) than large animal practices (56.4%). Common causes of injury of companion animal staff included; clinical examination (28.2%); falls, slips and trips (11.2%); drug administration (10.4%), and needlesticks and surgical sharps injuries (6.1%). LimitationsSurvey responses could not be directly linked to audit records due to anonymity, and survey-based prevalence estimates assumed only one injury per person per year, likely underestimating true injury rates. ConclusionsOccupational injury under-reporting is widespread in UK veterinary practices, particularly companion animal practices. Without improving reporting, it will be challenging to establish the true incidence and context of occupational injuries in the veterinary workforce. Strengthening reporting, training, leadership engagement, and visible responses to incidents are key to strengthening safety culture and injury reporting. HighlightsO_LIFor every 100 veterinary workplace injuries, 69 will go unreported C_LIO_LIIn clinical roles, companion animal vets had the highest rate of underreporting,78% C_LIO_LINeedlesticks and hazardous exposures more common than expected C_LIO_LIMany preventable injuries occur to practice visitors C_LIO_LIReporting can improve with training, leadership, and visible incident responses C_LI

The European Badger (Meles meles) is a wildlife host for Mycobacterium bovis, the causative agent of bovine tuberculosis (TB) in cattle. In England, large scale badger culling has been implemented since 2013 as part of a licenced Badger Control Policy (BCP). While several studies have shown an association between the BCP and disease benefits in cattle, a study by Langton et al. (2022) failed to identify any evidence of such benefits, raising questions about the effectiveness of badger culling as a tool for disease control. In this study I summarise the primary methodology used in the Langton et al. study and identify two significant issues with the approach used, which compares cattle TB incidence in culled areas of SW England to land without culling. Firstly, their analysis groups data together from cull areas into a combined culled vs unculled treatment, regardless of the time that culling has been applied. Secondly, there is evidence of a clear cull area selection bias, such that land enrolled into culling during the period analysed had a significantly higher baseline TB incidence than areas not culling. I then conducted a Monte Carlo analysis using simulated data under scenarios with differing cull effects, and matching the degree of grouping, selection bias and statistical methods used by Langton et al. (2022). The results indicate that even in scenarios with a relatively rapid and large effect of culling seeded into the simulation there is a significant probability that their analyses will fail to find an effect and may even wrongly conclude that culling is associated with an increase in TB. These results potentially explain the discrepancy between Langton et al. (2022) and other studies evaluating badger culling and highlight the importance of rigorous statistical analysis that accounts for temporal and spatial patterns in disease control data.

Human salmonellosis cases are often caused by Salmonella serovars Enteritidis and Typhimurium and a large percentage of Salmonella outbreaks is associated with the consumption of eggs and egg products. For this reason, many countries implemented general surveillance programmes for the detection and control of Salmonella on pullet and layer farms. The infection risk however varies between farms and the identification of risk factors for Salmonella infection may be used to improve the performance of these surveillance programmes. The aims of this study are therefore to determine 1) whether local farm density is a risk factor for the infection of pullet and layer farms by Salmonella Enteritidis and Typhimurium and 2) whether the sampling effort of surveillance programmes can be reduced by accounting for this risk factor, while still providing sufficient control of target serovars Enteritidis and Typhimurium. To assess the importance of local farm density as a risk factor, we fitted different transmission kernels to Israeli surveillance data during the period from June 2017 to April 2019. The analysis showed that the distance to infected farms significantly increases the infection risk by serovar Enteritidis within an approximately 4 km radius and by Typhimurium within an approximately 0.3 km radius. We subsequently used these kernels to derive a model for the between-farm R0 and used it to optimise a surveillance programme that subdivided layer farms into groups at low and at high risk of between-farm transmission based on the local farm density and allowed the sampling frequency to vary between these groups. In this design, the pullet farms were always sampled one week prior to pullet distribution. Our analysis showed that the risk-based surveillance programme was able to keep the between-farm R0 of serovars Enteritidis and Typhimurium below 1 for all pullet and layer farms, using a sampling effort that was reduced by 32% compared to the currently implemented surveillance programme in Israel. The results of our study therefore indicate that local farm density is an important risk factor for infection of pullet and layer farms by Salmonella Enteritridis and Typhimurium and can be used to improve the performance of surveillance programmes.

Direct and indirect interactions between livestock and free-ranging wildlife creates important risks to animal health and agricultural productivity. The interface between newly established and rapidly spreading invasive wild pigs and the 2,549 domestic pig farms on the Prairie Provinces of western Canada has created important but poorly understood disease transmission risks. We mapped the spatial overlap of wild and domestic pigs to identify the areas of highest risk and associated distribution of diseases of concern using databases of wild pig occurrences and domestic pig farm locations. We also examined spatial and temporal overlap at the individual farm scale using GPS collared invasive wild pigs. Across the provinces of Alberta, Saskatchewan, and Manitoba, spatial overlap of invasive wild pigs with all combined, large-scale domestic pig farms, small-scale domestic pig farms, and domestic wild boar farms was 21%, 21%, 21%, and 53%. Invasive wild pig locations were significantly closer to domestic pig farms and domestic wild boar farms compared to random points on the landscape. The number of wild pig occurrences was greatest within 20 km of domestic pig farms and decreased linearly as distance increased. The Canadian distribution of wild pigs had considerable spatial overlap with recent areas detected with bovine tuberculosis (6,002 km2) in livestock and wildlife and Chronic Wasting Disease (156,159 km2) in wildlife, including mule deer, white-tailed deer, elk, and moose. The single best predictor of invasive wild pig occurrences across the landscape was close proximity to current or recently past existing domestic wild boar farms. The distance of GPS- collared wild pigs was significant for sex, farm type, month, and season and in southeastern Saskatchewan, average distance to domestic pig farms was 5.3 km. The weighted sum of cover type proportions, wild pig distance to domestic pig and wild boar farms, farm type, and farm density identified the relative risk of wild pig presence associated to each domestic pig farm occupied watershed. Risk was highest for small-scale domestic pig farms and lowest for large- scale domestic pig farms. Our findings highlight important potential routes for disease transmission at the invasive wild pig-domestic pig interface and identify areas where biosecurity improvements are urgently needed. While complete eradication of invasive wild pigs in Canada is no longer achievable, improved passive and active monitoring and removal of wild pigs is critical, especially where risks to domestic pig herds is highest.

Since 2015, French poultry production is threatened almost every year by a reintroduction of highly pathogenic avian influenza H5 viruses. The duck sector was the most concerned by this crisis but other sectors such as broiler, layer and turkey were also affected by outbreaks. The objective of this work was to assess the risk of highly pathogenic avian influenza H5 virus transmission from one farm to another within the French broiler and layer production network. This study used the WOAH risk assessment framework. After drawing up a scenario tree of virus transmission from one farm to another, data were collected through a literature review or through experts elicitation. Three questionnaires were developed according to the experts field of expertise: avian influenza, broiler and layer sectors. The experts estimates were combined using a beta distribution weighted by their confidence level. A Monte Carlo iteration process was used to combine the different probabilities of the scenario tree and to assess the transmission risk. In the broiler sector, the highest transmission probabilities were observed if the exposed farm was an indoor broiler farm and the source a broiler farm (indoor or free-range). The high transmission probability between broiler farms integrated within the same association suggests that integration is an important risk factor. Person movement, transport of feed and manure management were the pathways with the highest transmission probabilities between two integrated indoor broiler farms with good biosecurity levels. In the layer sector, the highest transmission probabilities were observed if the source farm was a free-range farm and the exposed farm a production farm (indoor or free-range). The pathways with the highest transmission probabilities were egg transport and person movement. The sensitivity analysis showed that the exposed farms biosecurity had a significant impact on the transmission probability. Our results provide an insight on the role of each type of farms in the virus spread within the French broiler and layer production sectors and will be useful for the implementation of control measures such as movement restriction or vaccination.

Free-roaming dog populations pose challenges to public health and animal welfare, and their management and protection is legally mandated in many countries to control zoonotic diseases such as rabies, reduce bites, mitigate fear of aggressive dogs, and preserve animal welfare. Although international organisations recommend holistic dog population management with surgical sterilisation as a key component, stakeholders report a lack of evidence-based guidance on effective and cost-efficient strategies. To address this, we developed a deterministic model of a closed free-roaming dog (FRD) population, including dogs dependent on and independent of humans, parameterised using data from southern India. We evaluated a wide range of sterilisation strategies varying duration, interval, frequency, intensity, targeting different population subsets, and fixed or responsive approaches. Strategies were assessed based on their effects on independent FRD population size and implementation costs. Female sterilisation coverage (FSC) strongly determined population reduction and cost-effectiveness. Repeated, short sterilisation periods with appropriately timed intervals and high early intensity best balanced population reduction and cost-efficiency. Excluding dependent dogs (cared for by humans) severely constrained population reduction, while male sterilisation enhanced impact at little extra cost, assuming direct effects on pregnancy rates. Costs and population impacts can be visualised on an interactive web application (https://field.shinyapps.io/DogPopSimApp), allowing practitioners and policymakers to explore sterilisation strategy outcomes. Overall, cost-effective population reduction required sustained commitment and coverage-driven strategies that balance welfare, population reduction and the operational needs of dog-mediated rabies control.

Porcine reproductive and respiratory syndrome (PRRSV) remains costly for the swine industry. Measures intended to irradicate or reduce the prevalence of PRRSV have limited effectiveness. Vaccination, the primary control strategy for PRRSV, has yet to be thoroughly investigated to ensure an optimal strategy is being implemented. Due to insufficient cross-immunity between strains, it is prudent to administer the most influential vaccine for the most dominant or threatening PRRSV strain in circulation at a given time. With this in mind, we demonstrated the benefits of targeted vaccination using metapopulation-based modeling. By using up-to-date data describing real farms to simulate the effects of variable vaccine efficacy in both a single and a double strain system, we showed that tailoring vaccines to prevalent PRRSV strains reduces infections, but using multiple vaccines may be more effective if strains vary in vaccine response. Therefore, the impact of the strain-specific effectiveness of market vaccines, paired with computational methods that allow tracking the effects on PRRVS dissemination at individual barns.

Salmonella Dublin infections in heifer-raising operations (HROs) cause animal health and economic losses for these operations and represent a pathogen source for dairy farms obtaining replacement heifers from HROs. To improve control of S. Dublin, we (i) developed a mathematical model of S. Dublin transmission on a HRO, (ii) evaluated the vaccine effectiveness and cleaning improvements for controlling the infection, and (iii) evaluated the influence of infection and control strategies on the HROs operating income. We developed a modified Susceptible-Infected-Recovered-Susceptible model of S. Dublin spread in a batch-stocking HRO post-introduction of an index case, with stochasticity introduced through Monte Carlo simulations. Epidemiological outcomes (S. Dublin-induced deaths and abortions during raising and S. Dublin carriers and asymptomatic infections among raised replacement heifers) and operating income per 100-head raised on a HRO over a 2-year simulation were compared between control scenarios. We validated our model against S. Dublin infection data in cattle. Partial rank correlation coefficient and classification trees were used to determine parameter influence on model outcomes. Our model predicts a median of 37 carriers and 92 asymptomatic infections among raised replacement heifers out of 2,330 heifers that departed the operation by the end of the 2-year simulation period, highlighting the critical role of HROs in spreading S. Dublin. Increasing barn floor cleaning frequency (to a maximum of 12x per day) meaningfully reduced the S. Dublin epidemiological outcomes and improved the HROs operating income. Depending on the cost of cleaning, the median operating income increased between 1.2% to 10.6% in the first year when cleaning 12x per day compared to baseline (cleaning 1x per week). In most cost scenarios, predictions do not support the use of vaccination, even when paired with stringent cleaning measures. The developed model is expected to aid efforts to control S. Dublin in HROs.

Foot-and-mouth disease (FMD) is known to infect multiple food-animal species and to spread among ungulate populations. We introduce a multiscale compartmental stochastic model that incorporates population dynamics, births, deaths, and species-specific transmission dynamics. The model integrates disease dynamics at both the between-farm and the within-farm levels. We developed four scenarios to evaluate the effectiveness of countermeasures, including movement standstill, vaccination, and depopulation. The base scenario involved vaccinating the animals on 20 farms and depopulating four infected farms. The three alternative control scenarios included increasing vaccination and depopulation capacities and no vaccination. Our findings indicate that bovines were the most frequently infected species, followed by swine and small ruminants. After ten days of initial spread, the number of infected farms ranged from 1 to 123, with most simulations (90.12%) predicting fewer than 50 infected farms. Most of the secondary spread occurred within a range of 25 km. Early response to initiating the control action reduces the number of days spent working on control actions while intensifying daily depopulation and vaccination capacity; this may be worth considering in decision-making processes for future control of FMD. Emergency vaccination proved to be efficient in reducing the magnitude and duration of outbreaks, whereas increasing depopulation without the use of vaccination also proved to be effective in eliminating the outbreaks.

Antimicrobial stewardship (AMS) is essential for mitigating antimicrobial resistance (AMR) in animal health but implementing national initiatives is challenging due to diverse influencing factors and the need for context-specific approaches. An Animal AMS Practice Group, comprised of individuals with lived experience overseeing AMS in various animal health contexts was engaged, and through an experience-based co-design approach created a comprehensive AMS Framework that captures progress and supports tangible improvements in AMS practices in each context. The Framework supported a cross-sectoral pilot assessment that helped users identify progress, areas for improvement, and contextualise antimicrobial usage and AMR data, while also motivating further AMS efforts. Despite common barriers to sharing sensitive data, participants willingly shared AMS results for benchmarking and publication. The process demonstrated that co-design coupled with peer learning and expert support are essential to ensuring AMS tools are utilised in practice. Several participants incorporated the Framework into routine practice, with some using it to drive sector-level AMS action. The resulting Framework offers an adaptable, scalable entry point for AMS efforts and a platform for setting meaningful improvement goals. It supports broader opportunities for national-level AMS assessments and strategy development. Impact StatementThis research offers a practical, scalable approach to improving AMS in animal health. By embedding behaviour change into the project through an experience-based co-design process, rather than expecting it to occur afterward, veterinarians, animal managers, and other frontline professionals defined what good AMS looks like in their context and identified achievable actions to improve daily practices that aligned across diverse animal health settings. The resulting AMS Framework provides a clear, accessible starting point for those overseeing daily AMS activities to benchmark practices, set meaningful goals, and track progress, while also informing national-level prioritisation and decision-making. This user-led model demonstrates that when AMS tools are co-developed with those who will use them and users are empowered to shape the projects design and outputs, the resulting tools are more likely to be adopted, shared, and sustained.

Introductions of foreign animal diseases (FADs) into free-ranging wildlife can be difficult to control and devastating for domestic livestock trade. Combating a new FAD introduction in wildlife with an emergency response requires quickly limiting spread of the disease by intensely removing wild animals and recovering their carcasses for proper disposal. In the case of African swine fever virus (ASFv) in wild pigs (Sus scrofa), which has been spreading in many regions of the world, there is little information on the time- and cost-efficiency of methods for intensively and consistently removing wild pigs and recovering carcasses in an emergency response scenario. We compared the efficiencies of aerial operations, trapping, an experimental toxic bait, and ground shooting in northcentral Texas, USA during two months in 2023. Removing and recovering carcasses of wild pigs averaged a rate of 0.15 wild pigs/person hour and cost an average of $233.04/wild pig ($USD 2023) across all four methods. Aerial operations required the greatest initial investment but subsequently was the most time- and cost-efficient, costing an average of $7,266 to incrementally reduce the population by 10% including recovering carcasses. Aerial operations required a ground crew of [~]7 people/helicopter to recover carcasses. Costs for reducing the population of wild pigs using trapping were similar, although took 13.5 times longer to accomplish. A benefit of trapping was carcass recovery was incorporated. Toxic baiting was less efficient because carcass recovery required substantial time, and we removed very few wild pigs with ground shooting in this landscape. We recommend combining aerial and trapping methodologies to remove wild pigs and their carcasses efficiently and effectively during a FAD response. Overall, our findings can inform the preparation of resources, personnel needs, and deployment readiness for FAD responses involving wild pigs.

Disease prevention and control tactics rely on identifying and restricting animal movement to attenuate the between-premises spread of disease in livestock systems. Therefore, it is essential to uncover between-premises movement dynamics, including shipment distances and network-based control strategies. Here, we analyzed three years of between-premises pig movements, which include 197,022 unique animal shipments, 3,973 premises, and 391,625,374 pigs shipped across 20 U.S. states. We constructed unweighted, directed, temporal networks at 180-day intervals to calculate premises-to-premises movement distances, the size of connected components, network loyalty, and degree distributions, and, based on the out-going contact chains, identified network-based control actions. Our results show that the median distance between premises pig movements was 74.37 km, with median intrastate and interstate movements of 52.71 km and 328.76 km, respectively. On average, 2,842 premises were connected via 6,705 edges, resulting in a weak giant connected component that included 91% of the premises. The premises-level network exhibited loyalty, with a median of 0.65 (IQR: 0.45 - 0.77). Results highlight the effectiveness of node targeting and disease spread; we demonstrated that targeting 25% of farms with the highest degree or betweenness limited spread to 1.23% and 1.7% of premises, respectively. While there is no complete shipment data for the entire U.S., our multi-state movement analysis demonstrated the value and the needs of such data for enhancing the design and implementation of proactive-disease control tactics.

BackgroundWhile veterinary surgeons are known to have particularly high rates of injury compared to other sectors, little is known about rates of injury among veterinary students. This study aims to understand animal-related injury rates, injury context and mechanisms, attitudes to reporting injuries, and behaviour change among UK and Irish veterinary students. MethodsA survey was distributed to students across all veterinary schools operating in the UK and Ireland in 2021. Questions explored participants experience of injury through asking about their most recent and most severe injuries via quantitative and free-text questions. Data were analysed using descriptive statistics, logistic regression, and qualitative content analysis. Results533 responses were included in the analyses. Overall, 47.5% of students reported having been injured by an animal during the veterinary degree, 35.5% of students reported being injured within the last 12 months. Most recent injuries were caused by companion animals (38.0%), livestock (37.6%), and equids (23.5%). For their most severe injuries, 48.7% involved livestock, 28.7% companion animals, and 22.1% equids. The content analysis highlighted that students normalised injuries and infrequently reported injuries to the university. It was very rare for students to take time off from their studies or placements, due to course pressures. ConclusionsThese findings reflect concerningly high levels of injury, which are being under-reported and reflect a culture of injury acceptance and expectation among students. Veterinary schools should consider lessons learnt in other work environments which have been successful in changing safety culture.

Brucellosis imposes substantial impacts on livestock production and public health worldwide. A stochastic, age-structured model incorporating herd demographics was developed describing within- and between-herd transmission of Brucella abortus in dairy cattle herds. The model was fitted to data from a cross-sectional study conducted in Punjab State of India and used to evaluate the effectiveness of control strategies under consideration. Based on model results, stakeholder acceptance and constraints regarding vaccine supply, vaccination of replacement calves in large farms should be prioritised. Test and removal applied at early stages of the control programme where seroprevalence is high would not constitute an effective use of resources. Critically, under current model assumptions, significant numbers of animals removed (culled or not used for breeding) in this strategy would be removed based on false positive results. To achieve sustained reductions in brucellosis, policymakers must commit to maintaining vaccination in the long term, which may eventually reduce frequency of infection in the livestock reservoir to a low enough level for elimination to be a realistic objective. This exercise provided important insights into the control of brucellosis in India, which has the largest cattle population globally, and a general framework for evaluating control strategies in endemic settings.

BackgroundA novel subunit vaccine, DIVENCE(R), comprises different bovine respiratory and reproductive antigens, including BVDV-1 E2 recombinant glycoprotein and BVDV-2 E2 recombinant glycoprotein. This study evaluated the immune response against BVDV-1 and 2 generated by DIVENCE(R) over the long term in different strains. MethodsTwo different studies were conducted to assess the immune response induced by DIVENCE(R). In the first study, 20 seronegative young calves (55-104 days of age) were randomly distributed into the vaccinated or control group. All animals were given four intramuscular doses (D0, D21, D204 and D570) of 2 mL DIVENCE(R) or phosphate-buffered saline (PBS). Blood samples were collected to assess BVDV serum antibodies (ELISA) and neutralising antibodies (SN) against BVDV-1 and BVDV-2. In the second trial, heifers (from 10 months of age until calving) and cows (between first and seventh calving) were included and assigned to the vaccinated and control groups. Three different farms were enrolled in the study. The administration regimen was the same as described in the first study. Blood samples were collected from 32 random animals on each farm (16 vaccinated and 16 control animals). Additionally, bulk tank milk samples from each farm were obtained at different time-points and individual milk samples were obtained from vaccinated and control animals. The immune response against BVDV was analysed in serum and milk samples using different ELISA kits. Neutralising antibodies induced by DIVENCE(R) against different BVDV isolates from Europe and the Americas were also assessed in this trial. ResultsOverall, DIVENCE(R) induced high levels of total antibodies (ELISA) and neutralising antibodies against BVDV-1 and BVDV-2. These values were significantly (p<0.05) greater than the control group from 21 days after the second dose (D42) until the end of the study (D591). The high antibody levels, particularly after the third dose, were similar to those that described efficacy against experimental challenges of BVDV-1 and 2 in pregnant animals. In the field trial, similar results were observed in terms of total antibodies (ELISA) against BVDV, and no induction of anti-p80 antibodies was observed in vaccinated animals at any time. Additionally, analyses on individual and bulk tank milk samples also confirmed that no anti-p80 antibodies were induced in vaccinated animals. Furthermore, high levels of neutralising antibodies were observed against different BVDV isolates from Europe and the Americas. ConclusionThe DIVENCE(R) vaccine induced a strong immune response against BVDV-1 and BVDV-2, and this response allows infected and vaccinated animals to be differentiated (DIVA vaccine).

Re-evaluation of statistical analysis of the Randomised Badger Culling Trial (RBCT) by Torgerson et al. 2024 was rebutted by Mills et al. 2024 Parts I and II. The rebuttal defended the use of count rather than rate when considering bovine tuberculosis herd incidence. The defence makes biologically implausible use of Information Criterion for appraisal diagnostics; overfits data; and has erroneous Bayesian analyses. It favours goodness of fit over predictive power, for a small data set, when the study was to inform application. Importantly, for total bTB breakdown: ( confirmed (OTF-W) +unconfirmed (OTF-S)), where modern interpretation of the main diagnostic bTB test better indicates the incidence rate of herd breakdown, there is no effect in cull and neighbouring areas, across all statistical models. The RBCT was a small, single experiment with unknown factors. With respect to the paradigm of reproducibility and the FAIR principles, the original RBCT analysis and recent efforts to support it are wholly unconvincing. The 2006 conclusion of the RBCT that "badger culling is unlikely to contribute positively to the control of cattle TB in Britain" is supported, but the route to such a position is revised in the light of modern veterinary understanding and statistical reappraisal.

Field methods to diagnose bovine respiratory disease (BRD) do not accurately identify airway inflammation and lack clinical sensitivity. New diagnostic modalities, such as thoracic ultrasound (TU), computer-assisted lung auscultation (CALA), and transtracheal wash (TTW), have recently emerged which may deliver accurate diagnosis and prediction of BRD in clinical settings. Therefore, we sought to compare TU, CALA, and TTW fluid cytologic assessment in stocker cattle at risk for BRD in a pilot study. We enrolled 17 high-risk mixed-breed beef steers, sampled 10 and 21 days after arrival and conventional management, in a pilot cross-sectional observational study. Cattle were examined daily for 82 days for clinical BRD. On day 10, 16 cattle received CALA, and 10 and 8 of these received TU and TTW, respectively. On day 21, 12 cattle received CALA and TTW, and 10 received TU. CALA was scored as 1-5. Lung consolidation and/or comet tails were evaluated by TU. TTW was evaluated by 200-cell differential count, with inflammation defined as >20% neutrophils. Relationships between each diagnostic test, and between diagnostic tests and clinical BRD, were evaluated by logistic regression (P<0.10). Fourteen cattle were treated for BRD. CALA scores ranged 1-3; three cattle had lung consolidation. On day 10, 5 of 6 cattle previously treated for BRD and 0 of 3 not treated had >20% TTW neutrophils. On day 21, 5 of 9 treated cattle and 1 of 3 not treated had >20% TTW neutrophils. No significant relationship between CALA, TU, and TTW inflammation existed. TTW inflammation was associated with BRD diagnosis (P=0.0586). CALA and TU results were unrelated to TTW inflammation. Cytologic assessment of TTW may improve antemortem diagnosis of BRD.

Ethiopia experiences devastating economic losses from an ongoing endemic burden of trans-boundary animal diseases (TADs). TADs are highly transmissible infectious diseases of animals, often able to spread rapidly with significant economic and public health consequences. Contagious bovine pleuropneumonia (CBPP), foot-and-mouth disease (FMD), and lumpy skin disease (LSD) are among the global priority TADs for cattle. In this study, we used responses from a survey about cattle disease delivered to livestock keepers across Ethiopia. We used generalized additive mixed models applying neighborhood cross-validation method which accounts for spatial dependence in the data to investigate the spatially variable relationships between bioclimatic variables and distribution of CBPP, FMD, and LSD in Ethiopia. We also developed model-based risk maps of these diseases using a geostatistical kriging method to guide knowledge-based decision making. The results show the risks of CBPP vary with altitude and relative humidity, risks of FMD with temperature and relative humidity, and of LSD with temperature and precipitation. The gaussian spatial smooth terms are all significant. The maps are produced using rigorous statistical analysis with very low prediction errors and can thus be considered reliable. Our results have implications for the impacts of climate change, and the vulnerability of communities in high-risk areas. The risk maps illustrate how such maps contribute to climate-informed disease early warning systems.