In recent years, nanoparticles have become a fashionable subject of research due to their sizes, shapes, and unique intrinsic physicochemical properties. In particular for the last 5 years, nano-Se has received tremendous attention in terms of its production, characteristic, and possible application for poultry/animal science and medical sciences. Indeed, Nano-Se is shown to be a potential source of Se for poultry/animal nutrition. However, there is an urgent need to address the questions related to nano-Se absorption, assimilation, and metabolism. It is not clear at present if major biological effects of nano-Se are due to Se-protein synthesis, direct antioxidant/prooxidant effects, or both. It is necessary to understand how metallic nano-Se can be converted into H2Se and further to SeCys to be incorporated into selenoproteins. The aforementioned issues must be resolved before nano-Se finds its way to animal/poultry production as a feed supplement and clearly this subject warrants further investigation.

Livestock interventions can improve nutrition, health, and economic well-being of communities. The objectives of this review were to identify and characterize livestock interventions in developing countries and to assess their effectiveness in achieving development outcomes. A scoping review, guided by a search strategy, was conducted. Papers needed to be written in English, published in peer-reviewed journals, and describe interventions in animal health and production. Out of 2739 publications systematically screened at the title, abstract, and full publication levels, 70 met our inclusion criteria and were considered in the study. Eight relatively high-quality papers were identified and added, resulting in 78 reviewed publications. Only 15 studies used randomized controlled trial designs making it possible to confidently link interventions with the resulting outcomes. Eight studies had human nutrition or health as outcomes, 11 focused on disease control, and four were on livestock production. Eight interventions were considered successful, but only four were scalable. We found good evidence that livestock-transfer programs, leveraging livestock products for nutrition, and helping farmers manage priority diseases, can improve human well-being. Our report highlights challenges in garnering evidence for livestock interventions in developing countries and provides suggestions on how to improve the quantity and quality of future evaluations.

Anthropogenic activities can lead to several devastating effects on the environment. The pollutants, which include the discharge of effluents, runoffs in the form of different lethal and sub-lethal concentrations of pesticides, heavy metals, and other contaminants, can harm exposed fauna and flora. The aquatic environment is the ultimate destination for many pollutants which negatively affect aquatic biodiversity and even can cause a species to become extinct. A pollutant can directly affect the behavior of an animal, disrupt cellular systems, and impair the immune system. This harm can be reduced and even mitigated by adopting proper approaches for the conservation of the target biota. Among aquatic organisms, cetaceans, such as the Yangtze finless porpoise, Irrawaddy dolphin, Ganges River dolphin, Amazon River dolphin, and Indus River dolphin, are at a higher risk of extinction because of lack of knowledge and research, and thus insufficient information with respect to their conservation status, management, and policies. Pneumonia is one of the leading causes of mass mortalities of cetaceans. This article reviews the limited research reported on stress and pneumonia induced by pollution, stress-induced pneumonia and immunosuppression, pneumonia-caused mass mortalities of aquatic mammals, and vaccination in wildlife with a specific focus on aquatic mammals, the role of genomics in vaccine development and vaccination, and the major challenges in vaccine development for biodiversity conservation.

Bovine respiratory disease (BRD) is one of the most common and costly diseases of beef cattle. Much research has been conducted to understand prevention, treatment, and economic impacts of this syndrome. Impacts from BRD occur in multiple phases of the beef industry including both pre- and post-weaned calves. This disease causes negative impacts due to production losses, treatment costs, and cattle mortality. The large scope of BRD impacts merits further research on effective prevention and intervention technologies to limit deleterious impacts to the cattle industry.

In 1991, USDA's National Animal Health Monitoring System (NAHMS) conducted its first dairy study, a baseline assessment that focused on the health and management of heifer calves. During the study, producers ranked respiratory disease among the top two most common health problems affecting dairy calves. Over the last 25 years, U.S. dairy producers have participated in six NAHMS studies, yielding a rich repository of information that has helped identify needs for research, extension, and education in the dairy industry. NAHMS’ most recent dairy study, conducted in 2014, provides the latest estimates on dairy cattle health and includes another in-depth look at heifer-calf health. While overall mortality in calves has decreased, bovine respiratory disease (BRD) remains an important cause of morbidity in calves. This raises the concern that BRD mitigation may be at a standstill on dairies. Research and on-farm experience have done much to elucidate the challenges associated with detection and perceived impacts of this complex disease. Continued development and implementation of new methods for monitoring health and detecting disease will provide additional tools to upend stalemating factors associated with BRD control, helping the dairy industry ‘turn a corner’ on this important disease.

Cattle producers and animal health professionals are increasingly frustrated by the inability to reduce the impacts of bovine respiratory disease (BRD). Improved BRD control is difficult due to the complex nature of the disease; the complexity of cattle industry structure and function; and the imbalance of economic incentives for enhanced BRD control. Success in improving BRD control will depend on an industry-wide comprehensive effort to address lifetime animal health issues as well as correcting or offsetting imbalances in economic benefits and costs for enhanced animal health management across cattle production sectors.

Bovine respiratory disease (BRD) is a frequent disease concern in dairy cattle and is most commonly diagnosed in young dairy heifers. The impact of BRD is highly variable, depending on the accuracy and completeness of detection, effectiveness of treatment, and on-farm culling practices. Consequences include decreased rate of weight gain, a higher culling risk either as heifers or as cows, delayed age at first service, delayed age at first calving, and in some cases, lower future milk production. In this data set of 104,100 dairy replacement heifers from across the USA, 36.6% had one or more cases diagnosed within the first 120 days of age with the highest risk of new cases occurring prior to weaning. Comparison of the raising cost for heifers with BRD and those without a recorded history of BRD resulted in an estimated cost per incident case occurring in the first 120 days of age of $252 or $282, depending upon whether anticipated future milk production differences were considered or not. Current market conditions contributed to a cost estimate that is significantly higher than previously published estimates, driven in part by the losses associated with selective culling of a subset of heifers that experienced BRD.

Bovine respiratory disease (BRD) is the leading cause of death in beef calves 3 weeks of age to weaning and is the leading cause of morbidity and mortality in beef feeding and finishing systems. Each outbreak of respiratory disease is the result of the completion of a sufficient cause, which might have also included components of viral and bacterial pathogens, a certain state of immunity, or other component causes of respiratory disease in cattle that we fail to understand. Disease is expressed when a sufficient cause is completed. Disease events we observe, such as the occurrence of BRD, usually have relationships with risk factors that are commonly the subject of epidemiologic research and the primary subject of this paper. However, it is important to understand that underlying systems produce those relationships and, ultimately, the occurrence of disease. The risk factors for BRD include a complex set of component causes that include bacterial and viral pathogens, level of host immunity, and environmental conditions that favor pathogen transmission and stress-induced susceptibility. During the post-weaning phase, these factors are superimposed on a system of marketing, transportation, and decisions made to support economic opportunity that further increase the risk for BRD.

Bovine respiratory disease (BRD) is the leading natural cause of death in US beef and dairy cattle, causing the annual loss of more than 1 million animals and financial losses in excess of $700 million. The multiple etiologies of BRD and its complex web of risk factors necessitate a herd-specific intervention plan for its prevention and control on dairies. Hence, a risk assessment is an important tool that producers and veterinarians can utilize for a comprehensive assessment of the management and host factors that predispose calves to BRD. The current study identifies the steps taken to develop the first BRD risk assessment tool and its components, namely the BRD risk factor questionnaire, the BRD scoring system, and a herd-specific BRD control and prevention plan. The risk factor questionnaire was designed to inquire on aspects of calf-rearing including management practices that affect calf health generally, and BRD specifically. The risk scores associated with each risk factor investigated in the questionnaire were estimated based on data from two observational studies. Producers can also estimate the prevalence of BRD in their calf herds using a smart phone or tablet application that facilitates selection of a true random sample of calves for scoring using the California BRD scoring system. Based on the risk factors identified, producers and herd veterinarians can then decide the management changes needed to mitigate the calf herd's risk for BRD. A follow-up risk assessment after a duration of time sufficient for exposure of a new cohort of calves to the management changes introduced in response to the risk assessment is recommended to monitor the prevalence of BRD.

Veterinary diagnostic labs (VDLs) are important service agencies providing essential diagnostic testing for a wide variety of domestic animal species as well as wildlife. They serve key roles in disease monitoring and diagnosis as well as surveillance for diseases of consequence. Of the many roles VDLs serve, one is being a member of the larger team of professionals dealing with the management of the bovine respiratory disease (BRD) complex. VDLs provide a number of services related to the management of BRD. These include disease outbreak investigation, abnormal morbidity characterization, routine monitoring, and biosecurity screening for a variety of infectious agents via methods such as necropsy and histopathology, bacterial culture, antimicrobial sensitivity testing, virus isolation, and serological assays. VDLs continue to look for better methods and assays as instrumentation technology also grows and improves. This is reflected in the growing proliferation of molecular-based assays that provide a high degree of sensitivity and specificity. Professional staff in VDLs work in collaboration with those in academia and private industry to conduct basic research focusing on a different aspect of the BRD complex. VDLs remain a primary source of the varied field-origin infectious agents associated with BRD that are used for research purposes.

Advances in molecular and proteomic technologies and methods have enabled new diagnostic tools for bovine respiratory pathogens that are high-throughput, rapid, and extremely sensitive. Classically, diagnostic testing for these pathogens required culture-based approaches that required days to weeks and highly trained technical staff to conduct. However, new advances such as multiplex hydrolysis probe-based real-time PCR technology have enabled enhanced and rapid detection of bovine respiratory disease (BRD) pathogens in a variety of clinical specimens. These tools provide many advantages and have shown superiority over culture for co-infections/co-detections where multiple pathogens are present. Additionally, the integration of matrix-assisted laser desorption ionization time of flight mass spectrometry (MS) into veterinary diagnostic labs has revolutionized the ability to rapidly identify bacterial pathogens associated with BRD. Recent applications of this technology include the ability to type these opportunistic pathogens to the sub-species level (specifically Mannheimia haemolytica) using MS-based biomarkers, to allow for the identification of bacterial genotypes associated with BRD versus genotypes that are more likely to be commensal in nature.

Increased antimicrobial resistance in bovine respiratory bacterial pathogens poses a threat to the effective control and prevention of bovine respiratory disease (BRD). As part of continued efforts to develop antimicrobial alternatives to mitigate BRD, the microbial community residing within the respiratory tract of feedlot cattle has been increasingly studied using next-generation sequencing technologies. The mucosal surfaces of upper and lower respiratory tracts of cattle are colonized by a diverse and dynamic microbiota encompassing commensal, symbiotic, and pathogenic bacteria. While a direct causal relationship between respiratory microbiota and the development of BRD in feedlot cattle has not been fully elucidated, increasing evidence suggests that the microbiota contributes to respiratory health by providing colonization resistance against pathogens and maintaining homeostasis. Certain management practices such as weaning, transportation, feed transition, and antibiotic application can disrupt the respiratory microbiota, potentially altering pathogen colonization. Microbiota-based approaches, including bacterial therapeutics that target restoring the normal respiratory microbiota, may provide new methods for mitigating BRD in feedlot cattle in place of antibiotics. In addition, the distinct bacterial respiratory microbial communities observed in BRD-affected and healthy feedlot cattle may allow for future application of microbiota-based techniques used in the diagnosis of BRD.

Bovine respiratory disease (BRD) treatment failure occurs when animals receiving a treatment regimen for BRD fail to directly return to health, resulting in chronic illness and a requirement for repeated treatments, sale for salvage slaughter, euthanasia or death. BRD treatment failure has both direct and indirect impacts. Direct impacts include costs to manage chronically ill animals, including those associated with BRD relapse treatment; reduced returns from animals sent for salvage slaughter, loss of the initial investment to purchase the animal and feed and other accumulated expenses to death, and costs associated with carcass disposal. Indirect impacts include costs of infrastructure requirements, and negative effects on animal welfare and employee morale.

In cattle treated for respiratory disease, resolution of clinical signs has been the mainstay of determining treatment response and treatment efficacy. Through the use of calf lung ultrasound, we have found that pneumonia can persist or recur in the face of antibiotic therapy, despite improved clinical signs, leading to greater risk of clinical disease and more antibiotic use in the future. This review will discuss the pros and cons of using clinical signs to define resolution of disease and discuss how to implement lung ultrasound to improve our ability to accurately measure the impact of antibiotic therapy in cattle with respiratory disease.

Bovine respiratory disease (BRD) is one of the most common indications for antimicrobial therapy in beef cattle production and research trials demonstrate that antibiotic therapy greatly improves clinical outcome for BRD. These trials also show that BRD treatment success rates are less than 100% and that there are opportunities to optimize antimicrobial prescribing and improve clinical outcomes if the underlying cause(s) of BRD treatment failures can be identified and addressed. As the etiology of BRD in an individual animal is frequently multi-factorial in nature; it is likely that BRD treatment failures also result from complex interactions between the drug, drug administrator, animal host, pathogens, and the environment. This review will focus specifically on the pharmacological aspects, specifically the interactions between the host and the drug and the drug and the drug administrator, of BRD treatment failures and the actions that veterinary practitioners can take to investigate and mitigate therapeutic failures in future cases.

Genomic variation exists in cattle that affects their susceptibility to the complex of pathogens responsible for bovine respiratory disease (BRD). Heritability estimates and genome-wide association analyses (GWAA) support the role of host genomic variation in BRD susceptibility. Heritability estimates for BRD susceptibility range from 0.02 to 0.29 depending on the population, the definition of the disease, and the accuracy of diagnosis. GWAA have identified genomic regions (loci) associated with BRD in beef and dairy cattle based on a variety of BRD diagnostic criteria. National standards need to be developed for BRD diagnostics and reporting to facilitate selection. Commercial genotyping is available to predict BRD susceptibility in dairy cattle and for the selection of replacement animals. Disease pathogen profiles vary by region and can result in genetic heterogeneity where different loci are important for susceptibility to different BRD pathogens. Although the identification of the BRD pathogens may not be critical for treatment, it is of paramount importance in identifying loci that render cattle susceptible to the disease. Identification of loci associated with host susceptibility to BRD provides a foundation for genomic selection to reduce disease and opens the possibilities to a better understanding of how the host defends itself.

Bovine respiratory disease (BRD) is of considerable economic importance to the dairy industry, specifically among young animals. Several studies have demonstrated that BRD has a significant genetic component, with heritabilities ranging from 0.04 up to 0.22, which could be utilized to select more resistant animals. Taking advantage of available genomic data will allow more accurate genetic predictions to be made earlier in an animal's life. The availability of genomic data does not negate the necessity of quality phenotypes, in this case, records of BRD incidence. Evidence has shown that genetic selection is possible through the use of producer-recorded health information. The national dairy cooperator database currently has minimal records on respiratory problems. There is an existing pipeline for these data to flow from events recorded by producers on the farm to the national database used for genetic evaluation. Additional data could also be collected through the expansion of currently utilized termination codes and used in conjunction with the records of direct health events. Selection for animals with improved BRD resistance is possible at the national level; however, collection of additional phenotypes remains a significant hurdle.

Bovine respiratory disease (BRD) is an important disease in dairy calves due to its long-lasting effects. Early identification results in better outcomes for the animal, but producers struggle to identify all calves with BRD. Sickness behavior, or the behavioral changes that accompany illness, has been investigated for its usefulness as a disease detection tool. Behavioral changes associated with BRD include decreased milk intake and drinking speed, depressed attitude, and less likelihood of approaching a novel object or stationary human. Behavioral measurements are useful, as they can be collected automatically or with little financial input. However, one limitation of many BRD behavioral studies includes the use of either lung auscultation or clinical signs as reference methods, which are imperfect. Additionally, external factors may influence the expression of sickness behavior, which can affect if and when behavior can be used to identify calves with BRD. Behavioral measures available to detect BRD lack adequate sensitivity and specificity to be the sole means of disease detection, especially when detection tools, such as calf lung ultrasound, have better test characteristics. However, using behavioral assessments in addition to other detection methods can allow for a robust BRD detection program that can ameliorate the consequences of BRD.

Assessment of behavior is a longstanding strategy to assist the diagnosis of clinical bovine respiratory disease (BRD) in beef cattle. Cattle with systemic inflammation caused by infectious pathogen(s) display predictable behavioral adaptations compared to healthy cohorts. Behavioral alterations in BRD-affected cattle include lethargy, social isolation, and anorexia. However, behavior assessment to support BRD case definition in the production setting is challenging because: (1) other bovine diseases cause behavior alterations similar to BRD; (2) cattle have inherent prey instinct to disguise sickness behavior during human evaluation; (3) labor constraints dictate very brief observation of animal behavior; and (4) traditional behavior assessment is subjective and agreement is often poor. Some of these challenges may be overcome with the use of advanced technologies that allow continuous, remote, and objective behavior assessment of individual cattle. Automated methodologies for behavior assessment include three-axis accelerometers that quantify physical behaviors, systems that document feeding/watering behavior, and triangulation systems that document spatial behavior. Each of these behavior-monitoring approaches generates unique information and may facilitate early detection of BRD compared to traditional methods. Nevertheless, adoption of behavior assessment technologies for BRD diagnosis in beef operations hinges upon improved detection, positive return on investment, and successful integration within existing BRD management practices.