Concepts in Understanding Infectious Disease Dynamics in Populations.

Veterinarians are better prepared to assist producers in disease prevention, control, and eradication when they understand the relationships among the agent, the host, and the environment. Although vaccination may reduce disease prevalence in a herd, test and selective removal remain the most common method of disease control.

Biosecurity Practices for Mycobacterium aviun subspecies paratuberculosis Infection, Salmonellosis, and Bovine Leukemia Virus on Cattle Operations.

Mycobacterium avium subspecies paratuberculosis infection, salmonellosis, and bovine leukosis virus are important dairy and beef cattle diseases from a health perspective. For herds without infection, keeping the disease out through testing of source herds should be prioritized. For herds with infection, control programs should be instituted and followed to reduce the prevalence and ultimately eliminate the disease.

Assessing the contribution of nonmarket factors to the market value generated by cow-calf operations in rangelands of the western USA: A true cost accounting approach.

Food system transformation requires a better understanding of the negative and positive externalities involved in food production and consumption. Although negative externalities have received substantial attention, positive externalities have been largely overlooked. True Cost Accounting (TCA) is an economic assessment aimed at accounting for externalities in food systems.

African Swine Fever: A Review of Current Disease Management Strategies and Risks Associated with Exhibition Swine in the United States.

African swine fever is a high-consequence foreign animal disease endemic to sub-Saharan Africa and the island of Sardinia. The U.S.

Evaluation of Immune Nanoparticles for Rapid and Non-Specific Activation of Antiviral and Antibacterial Immune Responses in Cattle, Swine, and Poultry.

Given the rapid potential spread of agricultural pathogens, and the lack of vaccines for many, there is an important unmet need for strategies to induce rapid and non-specific immunity against these viral and bacterial threats. One approach to the problem is to generate non-specific immune responses at mucosal surfaces to rapidly protect from entry and replication of both viral and bacterial pathogens. Using complexes of charged nanoparticle liposomes with both antiviral and antibacterial toll-like receptor (TLR) nucleic acid ligands (termed liposome-TLR complexes or ), we have previously demonstrated considerable induction of innate immune responses in nasal and oropharyngeal tissues and protection from viral and bacterial pathogens in mixed challenge studies in rodents, cattle, and companion animals.

Functional and molecular determinants of right ventricular response to severe pulmonary hypertension in a large animal model.

Right ventricular (RV) failure is the major determinant of outcome in pulmonary hypertension (PH). Calves exposed to 2-wk hypoxia develop severe PH and unlike rodents, hypoxia-induced PH in this species can lead to right heart failure. We, therefore, sought to examine the molecular and structural changes in the RV in calves with hypoxia-induced PH, hypothesizing that we could identify mechanisms underlying compensated physiological function in the face of developing severe PH.

Brief Report: Case Comparison of Therapy With the Histone Deacetylase Inhibitor Vorinostat in a Neonatal Calf Model of Pulmonary Hypertension.

Pulmonary hypertension (PH) is an incurable condition in humans; driven by pulmonary vascular remodeling partially mediated by epigenetic mechanisms; and leading to right ventricular hypertrophy, failure, and death. We hypothesized that targeting chromatin-modifying histone deacetylases may provide benefit. In this Brief Report we describe case comparison studies using the histone deacetylase inhibitor vorinostat (suberanilohydroxamic acid, 5 mg/kg/day for the first 5 study days) in an established model of severe neonatal bovine PH induced by 14 days of environmental hypoxia.

Cardiopulmonary remodeling in fattened beef cattle: a naturally occurring large animal model of obesity-associated pulmonary hypertension with left heart disease.

The obesity epidemic in developed societies has led to increased cardiovascular diseases including pulmonary hypertension associated with left heart disease (PH-LHD), the largest and fastest-growing class of PH. Similar to obese humans, PH and heart failure (HF) are increasingly recognized in North American fattened beef cattle. We hypothesized that PH and HF in fattened beef cattle are novel, phenotypically distinct manifestations of bovine PH arising from left ventricular (LV) dysfunction similar to obesity-related PH-LHD in humans.

A comparison of a novel time-based summary measure of dairy cow health against cumulative disease frequency.

Background: There is an increasing push for dairy production to be scientifically grounded and ethically responsible in the oversight of animal health and well-being. Addressing underlying challenges affecting the quality and length of productive life necessitates novel assessment and accountability metrics. Human medical epidemiologists developed the Disability-Adjusted Life Year metric as a summary measure of health addressing the complementary nature of disease and death.

Dairy cow disability weights.

Over the past 175 years, data related to human disease and death have progressed to a summary measure of population health, the Disability-Adjusted Life Year (DALY). As dairies have intensified there has been no equivalent measure of the impact of disease on the productive life and well-being of animals. The development of a disease-adjusted metric requires a consistent set of disability weights that reflect the relative severity of important diseases.

Teaching Tip: Teaching Animal Welfare through Competitive Judging Contests.

Animal welfare is an important aspect of veterinary responsibility, yet the current curriculum at many US veterinary schools provides little training in this field. The Animal Welfare Judging and Assessment Contest provides an opportunity for students to learn about general principles of animal welfare, challenging them to apply critical reasoning skills in a competitive environment. Here we provide an overview of the contest and an example of how Colorado State University educates and prepares its students.

Survey of animal welfare, animal behavior, and animal ethics courses in the curricula of AVMA Council on Education-accredited veterinary colleges and schools.

OBJECTIVE To explore the extent to which veterinary colleges and schools accredited by the AVMA Council on Education (COE) have incorporated specific courses related to animal welfare, behavior, and ethics. DESIGN Survey and curriculum review. SAMPLE All 49 AVMA COE-accredited veterinary colleges and schools (institutions).

Myosin heavy chain 15 is associated with bovine pulmonary arterial pressure.

Bovine pulmonary hypertension, brisket disease, causes significant morbidity and mortality at elevations above 2,000 m. Mean pulmonary arterial pressure (mPAP) is moderately heritable, with inheritance estimated to lie within a few major genes. Invasive mPAP measurement is currently the only tool available to identify cattle at risk of hypoxia-induced pulmonary hypertension.

Impaired alveolar-arterial oxygen transfer is associated with reduced milk yield in primiparous post-partum dairy heifers at moderate altitude.

Domestic cattle have limited cardiopulmonary reserve for their body size and oxygen requirements. Therefore, it is plausible that impaired alveolar-arterial gas exchange may be detrimental to energetically expensive traits such as milk production which, like all aerobic processes, requires oxygen. The degree of alveolar-arterial oxygen transfer impairment can be determined by estimating the alveolar-arterial oxygen (A-a O2) pressure gradient from arterial blood-gas tensions.

Association between caudal fold tuberculin test responses and results of an ELISA for Mycobacterium avium subsp paratuberculosis and mycobacterial culture of feces in tuberculosis-free dairy herds.

OBJECTIVE--To evaluate associations between Mycobacterium avium subsp paratuberculosis (MAP) and caudal fold tuberculin (CFT) test results in cattle. DESIGN--Longitudinal and cross-sectional evaluations. ANIMALS--1 California (approx 3,600 cows) and 3 Colorado (approx 640, 1,190, and 1,480 cows) dairy herds considered free of Mycobacterium bovis infection.

An investigation into beef calf mortality on five high-altitude ranches that selected sires with low pulmonary arterial pressures for over 20 years.

Producer reports from ranches over 2,438 meters in southwest Colorado suggest that the mortality of preweaned beef calves may be substantially higher than the national average despite the selection of low pulmonary pressure herd sires for over 20 years. Diagnostic investigations of this death loss problem have been limited due to the extensive mountainous terrain over which these calves are grazed with their dams. The objective of the current study was to determine the causes of calf mortality on 5 high-altitude ranches in Colorado that have been selectively breeding sires with low pulmonary pressure (<45 mmHg) for over 20 years.

Control of paratuberculosis in dairy herds.

Control of Johne’s disease in dairy herds involves 3 basic steps: prevent exposure of calves to Mycobacterium avium subsp. paratuberculosis (MAP), identify and eliminate MAP-infected cows from the herd, and prevent entry of MAP-infected animals into the herd. Tailoring JD control programs to each specific dairy requires education of the producer and a full understanding of his/her goals, objectives, and resources.

Characterization of Mycobacterium avium subspecies paratuberculosis disseminated infection in dairy cattle and its association with antemortem test results.

Mycobacterium avium subspecies paratuberculosis (MAP) disseminated infection in dairy cattle affects animal health and productivity and is also a potential public health concern. The study objectives were to characterize MAP disseminated infection in dairy cattle and to determine the role of antemortem tests in detecting cattle with disseminated infection. Forty culled dairy cows representing a variety of serum enzyme-linked immunosorbent assay (ELISA) results and body conditions were selected for the study.

Consensus recommendations on diagnostic testing for the detection of paratuberculosis in cattle in the United States.

The report provided here contains a simplified set of diagnostic testing recommendations. These recommendations were developed on the basis of research funded by the USDA-Animal and Plant Health Inspection Service-Veterinary Services through a cooperative agreement. The report is intended to provide simple, practical, cost-effective consensus testing recommendations for cattle herds that are not enrolled in the US Test-Negative Program.

Training methods and association with worker injury on Colorado dairies: a survey.

The goals of this study were to define the current methods for training entry-level workers on Colorado dairies, to measure the relationship of training methods to the incidence of work-related injuries on those operations, and to characterize the nature and cause of injuries reported by participating workers. Seventy-two workers from 15 dairies from Weld, Morgan, Larimer and Yuma counties volunteered to be interviewed privately in the language of their choice. Training methods were classified by content (task training versus safety training), method of delivery (on-the-job verbal instruction, on-the-job demonstration, on-the-job supervision, classroom- based, and / or reading materials); and instructor (supervisor and/or co-worker).

Comparison of disease severity scoring systems for dairy cattle with acute coliform mastitis.

Objective: To compare use of 4 disease severity scoring systems to predict bacteremia (yes vs no) and outcome (survived vs died or culled) in dairy cows with acute coliform mastitis (ACM).

Design: Retrospective cohort study.

Animals: 99 dairy cows with ACM.

Risk of removal and effects on milk production associated with paratuberculosis status in dairy cows.

Objective: To determine effects on production and risk of removal related to Mycobacterium avium subsp paratuberculosis (MAP) infection at the individual animal level in dairy cattle.

Design: Longitudinal study.

Animals: 7,879 dairy cows from 38 herds in 16 states.

Artifactual hypoglycemia associated with hemotrophic mycoplasma infection in a lamb.

Background: A 35-day-old male lamb with Mycoplasma ovis infection (previously Eperythrozoon ovis) was evaluated because of severe hypoglycemia (serum glucose 4 mg/dL, Hitachi 704 automated chemistry analyzer) inconsistent with the animal's condition. Whole blood glucose concentration measured with a glucometer was 74 mg/dL.

Objective: The purpose of this study was to investigate this discrepancy through in vitro evaluation of the patient's blood.