Bovine Respiratory Disease (BRD) is a prevalent infectious disease of respiratory tract in cattle, presenting challenges in accurate diagnosis and forecasting due to the complex interactions of multiple risk factors. Common methods, including mathematical epidemiological models and data-driven approaches such as machine learning models, face limitations such as difficult parameter estimation or the need for data across all potential outcomes, which is challenging given the scarcity and noise in observing BRD processes. In response to these challenges, we introduce a novel approach known as the Bayesian Deep Mechanistic method.
View Article and Find Full Text PDFEpidemiological modeling is a key lever for infectious disease control and prevention on farms. It makes it possible to understand the spread of pathogens, but also to compare intervention scenarios even in counterfactual situations. However, the actual capability of decision makers to use mechanistic models to support timely interventions is limited.
View Article and Find Full Text PDFBovine respiratory diseases (BRDs) have major socioeconomic impacts in the beef sector. Antimicrobials have been traditionally used to prevent the development of BRDs upon arrival in fattening units. Currently, from a "One Health and One Welfare" perspective, alternative solutions are being investigated.
View Article and Find Full Text PDFMany questions are raised, and challenges faced in the new era of (intranasal) bovine respiratory disease complex vaccination. An increase in vaccination rate is expected, due to its positive impact on cattle health, reduction of antimicrobial use and economic factors. However, engagement of farmers and veterinarians with regard to vaccination is often affected by limitations, resulting in the development of barriers to vaccination, but also opportunities to overcome these.
View Article and Find Full Text PDFBovine Respiratory Disease (BRD) affects young bulls, causing animal welfare and health concerns as well as economical costs. BRD is caused by an array of viruses and bacteria and also by environmental and abiotic factors. How farming practices influence the spread of these causal pathogens remains unclear.
View Article and Find Full Text PDFBovine respiratory disease (BRD) dramatically affects young calves, especially in fattening facilities, and is difficult to understand, anticipate and control due to the multiplicity of factors involved in the onset and impact of this disease. In this study we aimed to compare the impact of farming practices on BRD severity and on antimicrobial usage. We designed a stochastic individual-based mechanistic BRD model which incorporates not only the infectious process, but also clinical signs, detection methods and treatment protocols.
View Article and Find Full Text PDFBackground: In the veal calf industry, bovine respiratory disease is the main cause of morbidity and mortality. Lung ultrasonography (LUS) is an accurate technique to diagnose bronchopneumonia in calves. Due to the economic constraints faced by the industry, a screening technique able to rapidly examine large numbers of calves is required.
View Article and Find Full Text PDFBovine viral diarrhoea (BVD) remains an issue despite control programs implemented worldwide. Virus introduction can occur through contacts with neighbouring herds. Vaccination can locally protect exposed herds.
View Article and Find Full Text PDFThis paper reports the design, fabrication and measured performance of a passive microelectromechanical transducer for the wireless monitoring of high irradiation doses in nuclear environments. The sensing device is composed of a polymer material (high-density polyethylene) sealed inside a cavity. Subjected to ionizing radiation, this material releases various gases, which increases the pressure inside the cavity and deflects a dielectric membrane.
View Article and Find Full Text PDFIn young cattle, bovine respiratory disease (BRD) is a major cause of death and is a frequent pathogen. Knowledge of fatal BRD in adult cattle is more limited. We assessed the importance of infectious BRD as a cause of death in adult cattle and determined the associated pathogens.
View Article and Find Full Text PDFBovine respiratory disease is still a major concern and has major economic impact. Another consequence of respiratory infections is the use of antimicrobial molecules to control bacterial pathogens. This can participate in the emergence and shedding of antimicrobial resistance that can threaten animal as well as human health.
View Article and Find Full Text PDFBovine respiratory diseases (BRD) are a major concern for the beef cattle industry, as beef calves overwhelmingly develop BRD symptoms during the first weeks after their arrival at fattening units. These cases occur after weaned calves from various cow-calf producers are grouped into batches to be sold to fatteners. Cross-contaminations between calves from different origins (potentially carrying different pathogens), together with increased stress because of the process of batch creation, can increase their risks of developing BRD symptoms.
View Article and Find Full Text PDFBovine respiratory syncytial virus (BRSV) and bovine parainfluenza-3 virus (bPI3V) are major causes of bovine respiratory disease (BRD) in newborn calves worldwide. Vaccination is widely used to prevent BRD, and intranasal vaccines for BRSV and bPI3V were developed to overcome interference from BRSV and bPI3V-specific maternally derived antibodies. Many experimental challenge trials have demonstrated that intranasal vaccines for BRSV and bPI3V are efficacious, but effectiveness under field conditions has been demonstrated less often, especially for newborn beef calves.
View Article and Find Full Text PDFBovine Nodular Thelitis (BNT) is a granulomatous dermatitis of teat skin associated with acid-fast bacilli. A similar condition has been recorded in a dairy goat flock in France recently. The causative agent was shown to be related to the leprosy-causing bacilli Mycobacterium leprae and M.
View Article and Find Full Text PDFTo meet the demands of the beef cattle sector in France, weaned beef calves are transported to sorting facilities and sorted into batches composed of animals of similar body weight (BW) before the beginning of the fattening period. This procedure aims to facilitate animal management. However, it leads to practices that affect animal welfare, health and performance, such as transporting weaned beef calves over long distances and mixing animals originating from different cow/calf farms.
View Article and Find Full Text PDFMicrobial access to host nutrients is a key factor of the host-pathogen interplay. With their nearly minimal genome, wall-less bacteria of the class have limited metabolic capacities and largely depend on host nutrients for their survival. Despite these limitations, host-restricted mycoplasmas are widely distributed in nature and many species are pathogenic for humans and animals.
View Article and Find Full Text PDFActinobacillosis usually is a sporadic infection that affects the tongue in cattle ("wooden tongue") with possible spread to the digestive tract. Two 4-year-old Rouge-des-Prés cows from a single French beef herd were referred for chronic (2-6 months) swelling and cutaneous nodules in the distal hind limbs. In addition to cutaneous signs, physical examination disclosed cachexia, lameness, lymphadenitis of the hind limbs, and pneumonia in both cows.
View Article and Find Full Text PDFType D bovine botulism outbreaks associated with poultry litter are increasingly reported in European countries, but the circumstances of exposure to Clostridium botulinum toxins remain unclear. In spring 2015, a large type D/C bovine botulism outbreak affected a farm with dairy and poultry operations. Epidemiological and laboratory investigations strongly suggest that the outbreak was caused by feeding cattle with insufficiently acidified grass silage that was contaminated by type D/C C.
View Article and Find Full Text PDFThe therapeutic efficacy of an early treatment protocol with an infection-stage adjusted fluoroquinolone regimen was evaluated in a field study on young bulls (YBs) presenting signs of bovine respiratory disease (BRD). A total of 195 YB (Charolais, Limousin, and Rouge-des-Prés breeds) from 6 farms implementing or not prophylactic antimicrobial treatments (PROPHY or absence) were randomly assigned to 1 of 2 experiment groups based on time of detection of BRD and first-line marbofloxacin regimen, early adjusted dose [Early 2 (E2)] or late standard dose [Late 10 (L10)]. Each YB was administered orally a reticulo-rumen bolus, allowing continuous monitoring of ruminal temperature.
View Article and Find Full Text PDFIn the context of requested decrease of antimicrobial use in veterinary medicine, our objective was to assess the impact of two doses of marbofloxacin administered on young bulls (YBs) and veal calves (VCs) treated for bovine respiratory disease, on the total population of Enterobacteriaceae in gut flora and on the emergence of resistant Enterobacteriaceae. In two independent experiments, 48 YBs from 6 commercial farms and 33 VCs previously colostrum deprived and exposed to cefquinome were randomly assigned to one of the three groups LOW, HIGH, and Control. In LOW and HIGH groups, animals received a single injection of, respectively, 2 and 10 mg/kg marbofloxacin.
View Article and Find Full Text PDFThe efficacy of an early and low inoculum-adjusted marbofloxacin treatment was evaluated on microbiological and clinical outcomes in calves infected with 4.10(7) CFU of Mannheimia haemolytica A1. Twenty-two calves were included based on their rectal temperature rise in the 10 h after challenge and allocated in four groups, receiving a single intramuscular injection of saline (CON), 2 mg/kg marbofloxacin 2-4 h after inclusion (early treatment, E2), 2 or 10 mg/kg marbofloxacin 35-39 h after inclusion (late treatments, L2, L10).
View Article and Find Full Text PDFChitin synthases play critical roles in hyphal development and fungal pathogenicity. Previous studies on Botrytis cinerea, a model organism for necrotrophic pathogens, have shown that disruption of Bcchs1 and more particularly Bcchs3a genes have a drastic impact on virulence (Soulié et al., 2003, 2006).
View Article and Find Full Text PDFMycoplasma bovis is an important cause of bovine respiratory disease (BRD) in newly received cattle at fattening operations. However, little information on its within-pen transmission dynamics during a BRD outbreak is available. Such information is nevertheless crucial to adapt control measures during M.
View Article and Find Full Text PDFThe primary objective of this study was to determine, at the lung level, whether single or multiple clones of Mannheimia haemolytica are present within a pen during a bovine respiratory disease (BRD) episode. A secondary objective was to assess whether M. haemolytica isolates obtained from nasal swabs (NS) are identical to those isolated deeper within the respiratory tract.
View Article and Find Full Text PDF