The role of major and minor determinants in penicillin allergy testing: Time to revisit an old friend?

Background

Skin testing is an important step in evaluation of penicillin allergic reactions. It includes testing to the following: amoxicillin, benzyl penicillin, and products generated in vivo after penicillin administration, the major determinant hapten penicilloyl-polylysine (PPL) and the minor determinant mixture (MDM). Although PPL and MDM are available as a commercial kit, their supply and cost remain problematic.

Objective

We aimed to evaluate the performance and utility of PPL and MDM in penicillin allergy testing.

Methods

A retrospective audit over a 5-year period was undertaken for those with penicillin testing in a tertiary immunology unit.

Results

In all, 214 patients were identified. Of those patients, 151 (70.6%) were female and the average age was 58 years. Unspecified penicillin was the most common index drug (n = 127 [59.3%]), followed by amoxicillin (n =3 [24.8%]) and amoxicillin-clavulanic acid (n = 21 [9.7%]). The result of skin testing was positive in 23 patients (10.7%); skin prick testing was positive in 10 patients (4.7%), and intradermal testing (IDT) was positive in 13 patients (6.1%), the majority of whom had identified amoxicillin or amoxicillin-clavulanic acid as the index drug (n = 22 [95.7%]). The result of testing to PPL and/or MDM was positive with IDT only (n=5 [23.8%]). PPL and MDM positivity coexisted with a positive reaction to amoxicillin IDT in 2 patients, 1 of whom passed an amoxicillin challenge. Additionally, 2 positive tests to PPL were present with a negative result for MDM; of these 2 positive results, 1 was positive to amoxicillin IDT. In only 1 case were the results of testing for MDM and PPL both positive, with negative results to all native β-lactams tested; the patient tolerated an amoxicillin challenge. Overall, the negative predictive value for both skin prick testing and IDT was 89.5%.

Conclusion

Benzyl penicillin and amoxicillin alone may be sufficient for in vivo testing in suspected individuals with penicillin allergy.

A multicenter chart review of patient characteristics, treatment, and outcomes in hereditary angioedema: unmet need for more effective long-term prophylaxis

BACKGROUND

Hereditary angioedema (HAE) is a rare disease characterized by unpredictable, recurring subcutaneous or submucosal swelling. Without effective therapy, HAE can negatively impact patients' quality of life. Management of HAE includes on-demand treatment of attacks and short- and long-term prophylaxis (LTP) to prevent attacks. Newer therapies may be more tolerable and effective in managing HAE; however, therapies such as androgens are still widely used in some countries owing to their relative ease of access and adequate disease control for some patients. This study evaluated the characteristics, treatment patterns, clinical outcomes, and healthcare resource utilization of a multinational cohort of patients with HAE, with a focus on understanding reasons for recommending or discontinuing available therapies.

METHODS

A retrospective chart review was conducted at 12 centers in six countries and included data from patients with HAE type 1 or 2 who were ≥ 12 years of age at their first clinical visit. The relationship between LTP use and attack rates was evaluated using a multivariable Poisson regression model. Data were collected between March 2018 and July 2019.

RESULTS

Data from 225 patients were collected (62.7% female, 86.2% White, 90.2% type 1); 64.4% of patients had their first HAE-related visit to the center prior to or during 2014. Treatment patterns varied between countries. Overall, 85.8% of patients were prescribed on-demand treatment and 53.8% were prescribed LTP, most commonly the androgen danazol (53.7% of patients who used LTP). Plasma-derived C1 inhibitor (Cinryze^®) was used by 29.8% of patients for LTP. Patients who received LTP had a significantly lower rate of HAE attacks than patients who did not receive any LTP (incidence rate ratio (95% confidence interval) 0.90 (0.84-0.96)). Androgens were the most commonly discontinued therapy (51.3%), with low tolerability cited as the most frequent reason for discontinuation (50.0%).

CONCLUSIONS

Overall, findings from this study support the use of LTP in the prevention of HAE attacks; a lower rate of attacks was observed with LTP compared with no LTP. However, the type of LTP used varied between countries, with tolerability and accessibility to specific treatments playing important roles in management decision-making.

Effects in air-exposed corn silage of medium chain fatty acids on select spoilage microbes, zoonotic pathogens, and in vitro rumen fermentation

Medium chain fatty acid (MCFA) treatment (0.75% C6, hexanoic; C8, octanoic; C10, decanoic; or equal proportion mixtures of C6:C8:C10:C12 or C8:C10/g; C12 = dodecanoic acid) of aerobically-exposed corn silage on spoilage and pathogenic microbes and rumen fermentation were evaluated in vitro. After 24 h aerobic incubation (37 °C), microbial enumeration revealed 3 log₁₀ colony-forming units (CFU)/g fewer (P = 0.03) wild-type yeast and molds in C8:C10-treated silage than controls. Compared with controls, wild-type enterococci decreased (P < 0.01) in all treatments except the C6:C8:C10:C12 mixture; lactic acid bacteria were decreased (P < 0.01) in all treatments except C6 and the C6:C8:C10:C12 mixture. Total aerobes and inoculated Staphylococcus aureus or Listeria monocytogenes were unaffected by treatment (P > 0.05). Anaerobic incubation (24 h at 39 °C) of ruminal fluid (10 mL) with 0.02 g overnight air-exposed MCFA-treated corn silage revealed higher hydrogen accumulations (P = 0.03) with the C8:C10 mixture than controls. Methane, acetate, propionate, butyrate, or estimates of fermented hexose were unaffected. Acetate:propionate ratios were higher (P < 0.01) and fermentation efficiencies were marginally lower (P < 0.01) with C8- or C8:C10-treated silage than controls. Further research is warranted to optimize treatments to target unwanted microbes without adversely affecting beneficial microbes.

Forages and pastures symposium: an update on in vitro and in situ experimental techniques for approximation of ruminal fiber degradation

Static quantification measures of chemical components are commonly used to make certain assumptions about forage or feed nutritive value and quality. In order for modern nutrient requirement models to estimate intake and digestibility more accurately, kinetic measures of ruminal fiber degradation are necessary. Compared to in vivo experiments, in vitro (IV) and in situ (IS) experimental techniques are relatively simple and inexpensive methods to determine the extent and rate of ruminal fiber degradation. This paper summarizes limitations of these techniques and statistical analyses of the resulting data, highlights key updates to these techniques in the last 30 yr, and presents opportunities for further improvements to these techniques regarding ruminal fiber degradation. The principle biological component of these techniques, ruminal fluid, is still highly variable because it is influenced by ruminally fistulated animal diet type and timing of feeding, and in the case of the IV technique by collection and transport procedures. Commercialization has contributed to the standardization, mechanization, and automation of the IV true digestibility technique, for example, the well-known DaisyII Incubator. There has been limited commercialization of supplies for the IS technique and several review papers focused on standardization in the last 30 yr; however, the IS experimental technique is not standardized and there remains variation within and among laboratories. Regardless of improved precision resulting from enhancements of these techniques, the accuracy and precision of determining the indigestible fraction are fundamental to modeling digestion kinetics and the use of these estimates in more complex dynamic nutritional modeling. Opportunities for focused research and development are additional commercialization and standardization, methods to improve the precision and accuracy of indigestible fiber fraction, data science applications, and statistical analyses of results, especially for IS data. In situ data is typically fitted to one of a few first-order kinetic models, and parameters are estimated without determining if the selected model has the best fit. Animal experimentation will be fundamental to the future of ruminant nutrition and IV and IS techniques will remain vital to bring together nutritive value with forage quality. It is feasible and important to focus efforts on improving the precision and accuracy of IV and IS results.

Forages and pastures symposium: forage biodegradation: advances in ruminal microbial ecology

The rumen microbial ecosystem provides ruminants a selective advantage, the ability to utilize forages, allowing them to flourish worldwide in various environments. For many years, our understanding of the ruminal microbial ecosystem was limited to understanding the microbes (usually only laboratory-amenable bacteria) grown in pure culture, meaning that much of our understanding of ruminal function remained a "black box." However, the ruminal degradation of plant cell walls is performed by a consortium of bacteria, archaea, protozoa, and fungi that produces a wide variety of carbohydrate-active enzymes (CAZymes) that are responsible for the catabolism of cellulose, hemicellulose, and pectin. The past 15 years have seen the development and implementation of numerous next-generation sequencing (NGS) approaches (e.g., pyrosequencing, Illumina, and shotgun sequencing), which have contributed significantly to a greater level of insight regarding the microbial ecology of ruminants fed a variety of forages. There has also been an increase in the utilization of liquid chromatography and mass spectrometry that revolutionized transcriptomic approaches, and further improvements in the measurement of fermentation intermediates and end products have advanced with metabolomics. These advanced NGS techniques along with other analytic approaches, such as metaproteomics, have been utilized to elucidate the specific role of microbial CAZymes in forage degradation. Other methods have provided new insights into dynamic changes in the ruminal microbial population fed different diets and how these changes impact the assortment of products presented to the host animal. As more omics-based data has accumulated on forage-fed ruminants, the sequence of events that occur during fiber colonization by the microbial consortium has become more apparent, with fungal populations and fibrolytic bacterial populations working in conjunction, as well as expanding understanding of the individual microbial contributions to degradation of plant cell walls and polysaccharide components. In the future, the ability to predict microbial population and enzymatic activity and end products will be able to support the development of dynamic predictive models of rumen forage degradation and fermentation. Consequently, it is imperative to understand the rumen's microbial population better to improve fiber degradation in ruminants and, thus, stimulate more sustainable production systems.

A Systematic Review of Physical Examination Components Adapted for Telemedicine

Introduction: The COVID-19 pandemic ushered in a rapid, transformative adoption of telemedicine to maintain patient access to care. As clinicians made the shift from in-person to virtual practice, they faced a paucity of established and reliable clinical examination standards for virtual care settings. In this systematic review, we summarize the accuracy and reliability of virtual assessments compared with traditional in-person examination tools. Methods: We searched PubMed, Embase, Web of Science, and CINAHL from inception through September 2019 and included additional studies from handsearching of reference lists. We included studies that compared synchronous video (except allowing for audio-only modality for cardiopulmonary exams) with in-person clinical assessments of patients in various settings. We excluded behavioral health and dermatological assessments. Two investigators abstracted data using a predefined protocol. Results: A total of 64 studies were included and categorized into 5 clinical domains: neurological (N = 41), HEENT (head, eyes, ears, nose, and throat; N = 5), cardiopulmonary (N = 5), musculoskeletal (N = 8), and assessment of critically ill patients (N = 5). The cognitive assessment within the neurological exam was by far the most studied (N = 19) with the Mini-Mental Status Exam found to be highly reliable in multiple settings. Most studies showed relatively good reliability of the virtual assessment, although sample sizes were often small (<50 participants). Conclusions: Overall, virtual assessments performed similarly to in-person exam components for diagnostic accuracy but had a wide range of interrater reliability. The high heterogeneity in population, setting, and outcomes reported across studies render it difficult to draw broad conclusions on the most effective exam components to adopt into clinical practice. Further work is needed to identify virtual exam components that improve diagnostic accuracy.

Study protocol: Australasian Registry of Severe Cutaneous Adverse Reactions (AUS-SCAR)

INTRODUCTION

Severe cutaneous adverse reactions (SCAR) are a group of T cell-mediated hypersensitivities associated with significant morbidity, mortality and hospital costs. Clinical phenotypes include Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalised exanthematous pustulosis (AGEP). In this Australasian, multicentre, prospective registry, we plan to examine the clinical presentation, drug causality, genomic predictors, potential diagnostic approaches, treatments and long-term outcomes of SCAR in Australia and New Zealand.

METHODS AND ANALYSIS

Adult and adolescent patients with SCAR including SJS, TEN, DRESS, AGEP and another T cell-mediated hypersensitivity, generalised bullous fixed drug eruption, will be prospectively recruited. A waiver of consent has been granted for some sites to retrospectively include cases which result in early mortality. DNA will be collected for all prospective cases. Blood, blister fluid and skin biopsy sampling is optional and subject to patient consent and site capacity. To develop culprit drug identification and prevention, genomic testing will be performed to confirm human leukocyte antigen (HLA) type and ex vivo testing will be performed via interferon-γ release enzyme linked immunospot assay using collected peripheral blood mononuclear cells. The long-term outcomes of SCAR will be investigated with a 12-month quality of life survey and examination of prescribing and mortality data.

ETHICS AND DISSEMINATION

This study was reviewed and approved by the Austin Health Human Research Ethics Committee (HREC/50791/Austin-19). Results will be published in peer-reviewed journals and presented at relevant conferences.

TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry (ACTRN12619000241134).

Licogliflozin for nonalcoholic steatohepatitis: a randomized, double-blind, placebo-controlled, phase 2a study

Nonalcoholic steatohepatitis (NASH) is a common chronic liver disease that may advance to fibrosis and lead to mortality; however, no pharmacotherapy is currently available. We tested the hypothesis that inhibition of both the sodium-glucose cotransporters 1 and 2 with licogliflozin would lead to improvement in NASH. A total of 107 patients with phenotypic or histologic NASH were randomized (1:2:2) to receive oral administration of either placebo (n = 21), licogliflozin 30 mg (n = 43) or 150 mg (n = 43) once daily for 12 weeks. Licogliflozin 150 mg showed a significant 32% (80% confidence interval (CI): 21-43%; P = 0.002) placebo-adjusted reduction in serum alanine aminotransferase after 12 weeks of treatment, the primary endpoint of the study. However, the 30 mg dose of licogliflozin did not meet the primary endpoint (placebo-adjusted reduction 21% (80% CI: 7-32%; P = 0.061)). Diarrhea occurred in 77% (33 of 43), 49% (21 of 43) and 43% (9 of 21) of patients treated with licogliflozin 150 mg, 30 mg and placebo, respectively, which was mostly mild in severity. No other major safety concerns were identified. Treatment with 150 mg licogliflozin led to reductions in serum alanine aminotransferase in patients with NASH. Studies of longer duration and in combination with drugs that have different mechanisms of action are needed to validate these findings and to define a role of licogliflozin as a therapeutic option for NASH. ClinicalTrials.gov identifier: NCT03205150.

The international WAO/EAACI guideline for the management of hereditary angioedema – The 2021 revision and update

Hereditary Angioedema (HAE) is a rare and disabling disease for which early diagnosis and effective therapy are critical. This revision and update of the global WAO/EAACI guideline on the diagnosis and management of HAE provides up-to-date guidance for the management of HAE. For this update and revision of the guideline, an international panel of experts reviewed the existing evidence, developed 28 recommendations, and established consensus by an online DELPHI process. The goal of these recommendations and guideline is to help physicians and their patients in making rational decisions in the management of HAE with deficient C1-inhibitor (type 1) and HAE with dysfunctional C1-inhibitor (type 2), by providing guidance on common and important clinical issues, such as: 1) How should HAE be diagnosed? 2) When should HAE patients receive prophylactic on top of on-demand treatment and what treatments should be used? 3) What are the goals of treatment? 4) Should HAE management be different for special HAE patient groups such as children or pregnant/breast feeding women? 5) How should HAE patients monitor their disease activity, impact, and control? It is also the intention of this guideline to help establish global standards for the management of HAE and to encourage and facilitate the use of recommended diagnostics and therapies for all patients.

Effects on weight loss and glycemic control with SAR441255, a potent unimolecular peptide GLP-1/GIP/GCG receptor triagonist

Unimolecular triple incretins, combining the activity of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon (GCG), have demonstrated reduction in body weight and improved glucose control in rodent models. We developed SAR441255, a synthetic peptide agonist of the GLP-1, GCG, and GIP receptors, structurally based on the exendin-4 sequence. SAR441255 displays high potency with balanced activation of all three target receptors. In animal models, metabolic outcomes were superior to results with a dual GLP-1/GCG receptor agonist. Preclinical in vivo positron emission tomography imaging demonstrated SAR441255 binding to GLP-1 and GCG receptors. In healthy subjects, SAR441255 improved glycemic control during a mixed-meal tolerance test and impacted biomarkers for GCG and GIP receptor activation. Single doses of SAR441255 were well tolerated. The results demonstrate that integrating GIP activity into dual GLP-1 and GCG receptor agonism provides improved effects on weight loss and glycemic control while buffering the diabetogenic risk of chronic GCG receptor agonism.

Preservation Method of Rumen Fluid Collected From Harvested Cattle Alters in vitro Digestibility of Reference Feedstuffs

The objective of our experiment was to evaluate preservation and revitalization strategies for rumen inoculum anticipating research and veterinary applications. Rumen fluid samples were collected from 12 harvested cattle. Liquid samples were divided into five 500-mL aliquots which were randomly allocated to one of five treatments in a 2 × 2 + 1 augmented factorial design. Factors included preservation method [freezing (FZN) or lyophilization (LYO)] and preservative (glycerol; + or –). A fresh control (CON) was maintained from each sample. Feedstuffs used in this experiment were alfalfa hay, Coastal bermudagrass hay, cracked maize, rice bran, and soybean meal. Reference feedstuffs were subjected to batch culture in vitro true digestibility (IVTD) and in vitro NDF digestibility (IVNDFD) assays using inoculum from each of the five treatments. There was an effect (P &lt; 0.05) of preservation method, preservative, and their interaction for both IVTD and IVNDFD of each of the five references feedstuffs. Freezing or lyophilization of rumen inoculum reduced (P &lt; 0.05) IVTD and IVNDFD of reference feeds relative to the CON. Despite lower degradation of feeds when frozen or lyophilized rumen fluid was used rather than fresh, differences between them in IVTD and IVNDFD suggest that, in the absence of fresh inoculum, preserved rumen fluid may be a viable option for veterinary applications, such as transfaunation, but likely will not be viable for research applications.

9 The Effects of Feeding Cannabidiol Oil on Behavior of Stalled Horses

Using cannabidiol (CBD) in animals has increased since the 2018 Agricultural Improvement Act was passed. Previous work in laboratory animals suggests supplementation with CBD reduced anxiety, compulsive behaviors, and brain activity of limbic and paralimbic areas. Horses exhibit anxiety due to training or housing situations, which is sometimes expressed via stereotypic behaviors including cribbing, aggression, etc. These behaviors can indicate underlying stressors and sometimes causes impairment; therefore, supplementing CBD may reduce undesirable behaviors in horses, consequently improving the health and overall welfare. The study objective was to determine if a single oral dose of CBD would result in adverse effects in horses. Four mature mares and four mature geldings were used in a randomized-control treatment design. Horses typically housed in paddocks, but not novel to stalling were housed in 11’ X 14’ stalls with cameras to record behavior, feed, and water intake. Horses were acclimated to feeding methods and stall environment for one week. Behavior was recorded for 24hr after a dosage of olive oil was administered as a control (CON). Horses were returned to their paddock for one week, then randomly assigned to either a LOW (0.3mg/kg BW; n = 4) or HIGH (0.6 mg/kg BW; n = 4) treatment of CBD oil. After oral dosing, horses were stalled for observation. Stereotypic behaviors such as pawing, cribbing, and aggression were quantified using the Observer XTTM program. Observations were analyzed in R Studio© for analysis of variance (ANOVA). The occurrence of stereotypic behaviors was lower (P = 0.03) in horses given oral CBD. Actions occurred more frequently during feeding sessions, behaviors including aggression and pawing occurred less when horses were given the High dose compared to Control (113 to 26 and 69 to 27) respectively. Based on results, oral administration of the particular cannabidiol product used in this study may mediate negative behaviors in stalled horses.

PSXIV-3 Mesquite wood as a grass replacement in silage production

Mesquite (Prosopis glandulosa Torr.) is considered an invasive browse species in most of the American Southwest. Over the past several decades, mesquite has spread rapidly in Texas, leading to destruction of native grasslands. In addition to trying to manage its encroachment on grazinglands, producers have been known to use mesquite wood in times of drought as a feed source for livestock, specifically in cow/calf production. This also represents a potential sustainable solution to dealing with debris from brush control measures. Thus, our objective was to evaluate the inclusion of chipped mesquite wood as a partial grass replacement in silage production. This experiment used a factorial treatment structure of silage inoculant (yes, no), grass replacement (0, 25, 50, 75, 100%), and length of incubation (28, 56, 82 d). Bermudagrass [Cynodon dactylon (L.) Pers. cv. Coastal] was used as the grass base in the silage mixtures. Samples were incubated in a convection incubator at 29.4°C for their respective incubation lengths. Following incubation, each sample was assayed for NDF, ADF, ADL, CP, and IVTD, as well as a silage acid profile. There was no effect of inoculation, grass replacement, or incubation time (P ≥ 0.13) on CP (μ = 10%), nor was there an effect of inoculation or grass replacement (P ≥ 0.67) on NDF (μ = 70%). Both ADF and ADL increased (P &lt; 0.05) with increasing inclusion of mesquite wood. In vitro true digestibility decreased (P &lt; 0.05) with increasing inclusion of mesquite wood (50% from grass silage; 40% from mesquite silage). Results are interpreted to mean that mesquite wood may be used as a grass replacement in silage production at low inclusion levels.

184 Statistical Analysis of Grazing Research

Research in the area of pastures, forages, and grazing livestock has a storied history within the realm of statistical analysis. Unlike traditional experiments in ruminant nutrition, in which an animal is fed individually and data are collected to assess the applied treatment, research on the grazing animal presents its own unique set of challenges. The collection of data on multiple scales (e.g., animal, pasture, landscape, time) brings into question the appropriate assignment of the experimental unit, and variance and covariance estimates must account for both the spatial and temporal effects of the environment. Oftentimes, the designs, assumptions, and rules-of-thumb taught to us in graduate school do not meet muster to adequately address the intricacies of this situation. This presentation will seek to address these complications and present statistically-sound solutions to obtain the maximum information from experimental data. First, a historical examination will be offered of how grazing experiments were originally handled. Next, conjecture will be offered as to why these methods may not remain valid and how advances in computing power and statistical theory allow us to obtain more information from the experiment. Finally, solutions to common scenarios will be offered whereby a more adequate or complete description of the experiment may be obtained.

PSXIV-12 Sources of variation in the nutritive value of hemp seed meal

The 2018 Farm Bill, with its groundbreaking hemp legislation, offered an alternative protein source to livestock producers. Hemp is the agricultural product of Cannabis sativa L. which must contain less than 0.3% tetrahydrocannabinol, the psychoactive component common to marijuana. Hemp oil, cold-pressed from C. sativa seed, has been gaining popularity over recent years for its use in cosmetics, pharmaceuticals, and human food products. Like most oilseeds, this leaves an oilseed meal with a potential for inclusion in livestock feeds. Thus, our objective was to quantify the sources of variation in the nutritive value of hempseed meal. Hempseed meal samples were obtained from commercial oil processing facilities (n = 4). Across these facilities, samples represented 15 independent hempseed meal batches. Our experimental design was a completely randomized design including the random effects of source, batch within source, and replicate within batch by source (laboratory replication). Samples were assayed for NDF, ADF, ADL, CP, and IVTD. Source had no contribution to variance for NDF, ADF, ADL, or CP (P ≥ 0.20). However, batch within source had a significant contribution to variation for NDF (μ = 50.1%; P = 0.01), ADF (μ = 36.8%; P = 0.01), ADL (μ = 12.9%; P &lt; 0.01), and CP (μ = 30.9%; P &lt; 0.01). Irrespective of the differences in nutritive value, there was no contribution to variation (P ≥ 0.23) of any measured effect on IVTD (μ = 53.0%). Results are interpreted to mean that, while variation exists among hempseed meal samples with respect to nutritive value, the viability of hempseed meal as a livestock feed source is strong.

PSII-14 Inclusion of popcorn and crawfish shells as components in non-feedstock silage production

As the future of agricultural sciences, it is imperative that student scientists seek to investigate alternatives to help improve production by lowering costs while meeting dietary requirements, increasing output, and maintaining sustainability. Anthropogenic waste as potential feedstock, we are engaging in an innovative wave of agricultural research. While previous research in our laboratory has evaluated newspaper, waste popcorn, and crawfish shells as feedstock, their potential for ensiling represents an alternative avenue for upcycling and long-term storage. The objective of this experiment was to determine the optimum concentrations of newspaper, waste popcorn, and crawfish shells for ideal silage fermentation. This experiment was conducted as a Box-Wilson composite design with four replications. Prescribed amounts of shredded newspaper, ground crawfish shells and heads, and waster popcorn were thoroughly mixed, and water and inoculant were added to achieve 25% dry matter. Central points for popcorn were 35.5, 1.3, 35.5, and 1.3% dry matter, respectively, for grain silage, grass silage, high combination, and low combination. Central points for crawfish were 4.0, 6.4, 4.0, and 6.4% dry matter, respectively, for grain silage, grass silage, high combination, and low combination. Samples were sealed using a food-grade sealer and allowed to ferment for 35 d. A subsample was frozen for assay of pH and silage acids. The remaining sample was dried at 55°C, ground, and assayed for NDF, ADF, CP, and IVTD. Across block, there was no effect of crawfish or popcorn inclusion on NDF (P ≥ 0.09; μ = 74%), ADF (P ≥ 0.24; μ = 60%), or IVTD (P ≥ 0.12; μ = 35%). Results are interpreted to mean that these feed ingredients may be used in non-feedstock silage production, but its usefulness to livestock production is questionable.

PSX-A-7 Late-Breaking: Correlation of mitochondrial membrane potential and rough motility scores in cryopreserved bovine spermatozoa

Spermatozoon motility is an important factor in successful artificial reproductive technologies. Successful reproduction requires properly developed spermatozoa with adequate forward, progressive motility that allows for transport through the female reproductive tract. Motility is driven by production of ATP; however, cryopreservation is known to have damaging effects on spermatozoa. Mitochondria utilize oxidative phosphorylation to synthesize ATP through an electrochemical proton motive force that is composed primarily of mitochondrial membrane potential (Δψm). The mitochondrial membrane potential can be measured using a fluorescent, carbocyanine JC-1 dye (5,5’,6,6’-tetrachloro-1,1’,3,3’-tetraethylbenzimi-dazolylcarbocyanine iodide). The objective of this study was to examine correlations between the mitochondrial membrane potential and motility score. Cryopreserved semen samples from three bulls were donated to Tarleton State University for research purposes. Samples were thawed, placed under a phase contrast microscope, and analyzed by three individuals with varying levels of training for rough motility. These samples were then prepared with JC-1 dye according to manufacturer’s instructions. Two microliters of dye were added to a stock preparation of each sample. Samples were examined on a FACS Calibur flow cytometer at University of Texas Southwestern Core in Dallas, TX. Flow cytometry analysis was performed using FlowJo V10.7. Statistical analysis was performed using SAS v9.4. The Pearson correlation coefficient showed a strong, positive correlation (r = 0.90) between the mitochondrial membrane potential and motility (P = 0.28), thus indicating as the mitochondrial membrane potential increases, so does the rough motility score. These data represent a subset of a population that demonstrates the need of further research on the ability for spermatozoa to produce ATP and the correlation in forward, progressive motility. This research can provide a foundation in which future researchers may develop an assay that allows for testing of mitochondrial membrane potential by producers to select bulls with greater breeding potential.

Impact of Longitudinal Virtual Primary Care on Diabetes Quality of Care

BACKGROUND

Lack of healthcare access to due to physician shortages is a significant driver of telemedicine expansion in rural areas. Telemedicine is effective for management of chronic conditions such as diabetes but its effectiveness in primary care settings is unknown.

OBJECTIVE

To evaluate differences in diabetes care before and after implementation of a longitudinal virtual primary care program.

DESIGN

Propensity score-matched cohort study utilizing difference-in-differences analysis.

PARTICIPANTS

Patients with diabetes who received care at VA primary care clinics between January 2018 and December 2019 where the Virtual Integrated Multisite Patient Aligned Care Teams (V-IMPACT) program was implemented.

EXPOSURE

Patient participation in at least one V-IMPACT visit while usual care patients did not participate in V-IMPACT.

MAIN MEASURES

The primary outcome was change in hemoglobin A1C (HbA1C) and secondary outcomes included change in the proportion of patients meeting diabetes quality indicators: blood pressure control, statin use, angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (ACEi/ARB) use, and annual microalbuminuria testing.

KEY RESULTS

Our propensity-matched cohort included 9010 patients split evenly between those who participated in V-IMPACT and those who remained in usual in-person care. Among individuals with diabetes who participated in V-IMPACT, the change in mean HbA1C was - 0.055% (95% CI - 0.088 to - 0.022%) while those in usual care had a - 0.047% (95% CI - 0.080 to - 0.014%) change before and after program implementation. We observed a 5.1% (95% CI 2.4 to 7.7%) absolute increase in the proportion prescribed statins in the V-IMPACT group, a 5.3% (95% CI 2.5 to 8.2%) increase prescribed ACE/ARBs, and a 4.6% (95% 1.7 to 7.5%) increase in completed yearly microalbuminuria testing. V-IMPACT was not associated with a significant difference in the proportion with controlled blood pressure at < 140/90 or < 130/90 mmHg thresholds.

CONCLUSIONS

Quality of diabetes care delivered by a longitudinal virtual primary care model was similar if not better than traditional in-person care.

Antibody semorinemab reduces tau pathology in a transgenic mouse model and engages tau in patients with Alzheimer's disease

Tau has become an attractive alternative target for passive immunotherapy efforts for Alzheimer's disease (AD). The anatomical distribution and extent of tau pathology correlate with disease course and severity better than other disease markers to date. We describe here the generation, preclinical characterization, and phase 1 clinical characterization of semorinemab, a humanized anti-tau monoclonal antibody with an immunoglobulin G4 (igG4) isotype backbone. Semorinemab binds all six human tau isoforms and protects neurons against tau oligomer neurotoxicity in cocultures of neurons and microglia. In addition, when administered intraperitoneally once weekly for 13 weeks, murine versions of semorinemab reduced the accumulation of tau pathology in a transgenic mouse model of tauopathy, independent of antibody effector function status. Semorinemab also showed clear evidence of target engagement in vivo, with increases in systemic tau concentrations observed in tau transgenic mice, nonhuman primates, and humans. Higher concentrations of systemic tau were observed after dosing in AD participants compared to healthy control participants. No concerning safety signals were observed in the phase 1 clinical trial at single doses up to 16,800 mg and multiple doses totaling 33,600 mg in a month.

Understanding intake on pastures: how, why, and a way forward

An assessment of dietary intake is a critical component of animal nutrition. Consumption of feed resources is the basis upon which feeding strategies and grazing management are based. Yet, as far back as 1948, researchers have lauded the trials and tribulations of estimation of the phenomenon, especially when focused on grazing animals and pasture resources. The grazing environment presents a unique situation in which the feed resource is not provided to the animal but, rather, the animal operates as the mechanism of harvest. Therefore, tools for estimation must be developed, validated, and applied to the scenario. There are a plethora of methods currently in use for the estimation of intake, ranging from manual measurement of herbage disappearance to digital technologies and sensors, each of which come with its share of advantages and disadvantages. In order to more firmly grasp these concepts and provide a discussion on the future of this estimation, the Forages and Pastures Symposium at the 2020 ASAS-CSAS-WSASAS Annual Meeting was dedicated to this topic. This review summarizes the presentations in that symposium and offers further insight into where we have come from and where we are going in the estimation of intake for grazing livestock.

PSI-30 Evaluation of urine estrone sulfate (P-Test) in beef cattle as an alternative pregnancy detection method

Pregnancy detection in cattle can be expensive and labor intensive to producers. A simple, cost-efficient method of determining early pregnancy, chute side, is lacking within the industry. This study tested various proven pregnancy detection methods against an alternative method. Pregnancy was assessed by ultrasonography, blood serum pregnancy-specific protein B (PSPB), and urine estrone sulfate (“P-Test”). A fixed timed AI (FTAI) protocol was conducted on 14 predominantly British cattle housed at Tarleton State University in Stephenville, TX. Cows were synchronized using the co-synch plus 7 day CIDR protocol, with PGF injection of d 7. Heifers were synchronized similarly with the exception of GnRH injection on d 1. Estrotech patch scores (1 – 4, 1 showing little signs of estrus to 4 presenting signs of estrus) were utilized to indicate estrus activity prior to FTAI (21.4% vs. 78.6% females scored 1 vs. 4, respectively). FTAI was performed on protocol d 10 along with a 2mL injection of GnRH. Serum for PSPB analysis was collected at d 30 and 60 post insemination, while urine was sampled on d 60. Overall 53.8% (ultrasonography) and 71.4% (PSPB) of cattle were determined to be pregnant at d 30 post FTAI. Chi squared analysis proved that PSPB and ultrasound were similar at detecting pregnancy (P = 0.04). At d 60 “P-Test” color varied indicating differing levels of estrone sulfate. A t-test revealed increased PSPB from d 30–60 post FTAI (P &lt; 0.0001); however, “P-Test” could not predict similar results (P = 0.655). Data suggest the “P-Test” is not a consistent method to diagnose early pregnancy. Future studies may be warranted to investigate a more desirable time point for utilizing the chute side “P-Test” as a reliable method to determine pregnancy.

PSVI-14 Effects of saturated fatty acids of 6 to 12 carbons in length on spoilage microbes, zoonotic pathogens and antimicrobial resistant bacteria in air exposed corn silage

Aerobic exposure of silage during the feed-out phase promotes growth of spoilage as well as pathogenic and multi-drug resistant (MDR) microbes which can risk infection of food-producing animals and the foods they produce. Livestock producers are interested in finding effective yet environmentally friendly interventions to preserve the nutritional value of these spoiled feedstuffs. We investigated the antimicrobial activity of 6 to 12 carbon-containing saturated fatty acids (C6, C8, C10 or C12) added (0.03 g) individually or as 1:1 mixtures of C6:C8:C10:C12 or C8:C10 to 4 g of overnight exposed silage suspended in 10 mL water. Net changes in colony counts, determined as the difference between counts measured after 0 and 24 h aerobic incubation (22oC) of untreated and treated silage suspensions (n = 3/treatment), were subjected to an analysis of variance. Populations of wild-type total aerobes and experimentally-inoculated MDR-Staphylococcus aureus were unaffected by treatment (P &gt; 0.05), decreasing on average (± SD) 0.64 ± 0.40 and 1.09 ± 0.39 log10 CFU/g silage, respectively. Treatment effects (P &lt; 0.05) were observed against experimentally-inoculated Listeria monocytogenes, with the C8:C10 mix decreasing this foodborne pathogen by 0.64 log10 CFU/g compared to a 0.95 log10/g increase in controls. Indigenous yeast and mold, considered responsible for spoilage, were decreased 2.12 and 3.07 log10 CFU/g by the C8 and C8:C10 treatments compared to 0.40 log10 CFU/g increase in controls. Indigenous lactic acid bacteria, considered beneficial, were decreased most potently by the C8 and C8:C10 treatments compared to controls (1.28, 0.66 and 0.37 log10 CFU/g, respectively). Indigenous enterococci decreased in all incubations, including controls (3.03 log10 CFU/g), compared to 4.69 to 5.03 log10 CFU/g decreases in C6, C8, C10, C12 and C8:C10 treatments. Results reveal that some fatty acid treatments inhibited pathogenic and spoilage microbes, yet treatment optimization is needed to avoid adverse effects against beneficial microbes.

PSII-20 Effects of aerobically exposed corn silage treated with medium chain fatty acids on rumen fermentation in vitro

Medium chain fatty acid (MCFA) treatment of aerobically exposed silage during feed-out is a potential strategy to prevent growth of spoilage and pathogenic microbes. To evaluate the effects of feeding MCFA-treated silage on the rumen fermentability, we incubated 0.02 g of overnight air-exposed corn silage that had been treated individually without or with (0.75% wt/wt) C6, C8, C10 or C12 or with equal proportion mixtures of C6:C8:C10:C12 or C8:C10 with 10 mL freshly collected ruminal fluid. Additions were made while flushing with CO2 and tubes (3 tubes/treatment) were then capped and sealed. After 24 h incubation at 39oC, headspace gases and fluid volatile fatty acids were measure using gas chromatography techniques. Results from a completely randomized analysis of variance revealed higher hydrogen accumulations (P &lt; 0.05) only in incubations containing silage treated with the C8:C10 MCFA mixture when compared to controls, with mean ± SD concentrations (µmol/mL incubation fluid) being 2.19 ± 1.6 versus 0.08 ± 0.04, respectively. Treatment effects were not observed (P &gt; 0.05) on accumulations (µmol/mL) of methane (13.25 ± 2.5), acetate (19.66 ± 5.6), propionate (7.27 ± 2.0), butyrate (12.36 ± 2.7) or stochiometric estimates of amounts of hexose fermented (41.39 ± 9.7), although the acetate:propionate ratios of incubations of silage treated with C8 or the C8:C10 mixture were higher (P &lt; 0.05) than those of untreated controls (3.46 ± 0.7, 3.46 ± 0.5 and 2.35 ± 0.1, respectively). Consequently, correspondingly estimates of fermentation efficiency, calculated based caloric energy values of amounts of acetate, propionate and butyrate relative to glucose, were slightly lower (P &lt; 0.05) for the incubations of silage treated with C8 and the C8:C10 mix compared to controls (74.36 ± 1.1, 74.82 ± 0.2 and 76.55 ± 0.3 %, respectively). Results reveal little negative effect of MCFA treatment on ruminal fermentability of silage.

254 Effect of presentation method on understanding of organic chemistry in an undergraduate animal nutrition course

An educator’s goal is to always explain classroom material to his or her students in the most efficient way possible. Chemistry is a fundamental foundation to the study of animal nutrition, but the concepts of organic chemistry are very difficult to relay to students of animal science, possibly due to the different types of student learners. It could be that mode of presentation may aid in relaying this information to the students. The sample for this experiment included students enrolled in an animal nutrition course at Tarleton State University. Students were presented with five methods of presentation of carbohydrate molecular structure in a laboratory session, each with an increasingly tactile approach: written description, printed 2-dimensional model, printed 3-dimensional model, ball-and-stick model, and self-constructing molecular model kit. Students were then asked to complete a survey to address effectiveness of presentation method. Data were analyzed using SAS v. 9.4. When addressing effectiveness of presentation method, the written description and the printed 2-dimensional model were rated as slightly-to-moderately effective (48.4 and 67.8%, respectively), the printed 3-dimensional model was rated as moderately effective (58.1%), the ball-and-stick model was rated as very effective (48.4%), and the self-constructing model was rated as very-to-extremely effective (80.6%). Cluster analysis revealed that students chose any of the presentation methods over the written description with preference for the self-constructing model. Results are interpreted to mean that presentation of organic chemistry concepts in animal nutrition are more effective when kinesthetic presentation methods are employed.

Pharmacokinetics and tolerability of fedratinib, an oral, selective Janus kinase 2 inhibitor, in subjects with renal or hepatic impairment

PURPOSE

Fedratinib is an oral, selective Janus kinase 2 inhibitor that is approved in the United States for the treatment of patients with intermediate-2 or high-risk myelofibrosis. Pharmacokinetics and tolerability of fedratinib in subjects with renal impairment (RI) and hepatic impairment (HI) were evaluated in two separate studies.

METHODS

In the renal study, male and female subjects with stable, chronic mild, moderate, and severe RI, as well as those with end-stage renal disease, were included. The hepatic study included subjects with stable, chronic mild HI. Both were phase 1, multicenter, open-label, single-dose studies, and included matched healthy subjects. Subjects received a single oral dose of fedratinib 300 mg on day 1, were discharged on day 4, returned for clinical visits on days 5-12, and had their end-of-study visit between days 14 and 16.

RESULTS

Thirty-six and 17 subjects were included in the renal and hepatic studies, respectively. In the renal study, fedratinib area under the plasma concentration-time curve from time 0 to infinity (AUC_inf) was 1.9- and 1.5-fold higher in subjects with severe and moderate RI, respectively, than in matched healthy subjects. In the hepatic study, fedratinib AUC_inf did not appreciably differ between subjects with mild HI and matched healthy subjects. Overall, most treatment-emergent adverse events were gastrointestinal and mild.

CONCLUSION

Mild RI and HI do not necessitate fedratinib dosage adjustments. Subjects with moderate RI should be monitored (with dosage adjustments made as necessary), whereas those with severe RI should receive a daily dose of 200 mg, reduced from the indicated dose of 400 mg.

Categorization of adverse drug reactions in electronic health records

The purpose of this study was to evaluate the quality of adverse drug reaction (ADR) documentation in a state-wide electronic health record (EHR), and to assess the impact of the interface design on documentation accuracy and ability to provide decision support. Data were extracted from 43 011 unique records in a state-wide electronic health record in South Australia, Australia. Information obtained included ADR coding as allergy or intolerance, allergen name, reaction, and occupation of those entering data. Categorization into drug allergy or intolerance was assessed for accuracy. Reactions were entered predominantly by nurses (60.1%), also by doctors (31.0%) and pharmacists (6.1%). Of 27 314 reactions, 86.5% were coded as allergy and 13.5% as intolerance. The majority (78.2%) described reactions to drugs (as opposed to food, environmental or contact allergens), predominantly chosen from the drug database (96.4%). Many entries used free text for the reaction description (27.4%). Terms found in the predefined list under the allergy heading were more likely to be categorized as allergy, even when the mechanism was pharmacological intolerance. Only 45.1% (n = 1671/3705) of reactions consistent with intolerance (eg, "nausea," "diarrhea") were correctly categorized as such, although categorization by pharmacists was more accurate (P < .0001). These data suggest that ADR categorization as allergy or intolerance is influenced by the EHR design. The obligatory classification of ADRs into allergy or intolerance was not well understood and does not appear to have practical benefit.

Biogeographical variation in specific IgE recognition of temperate and subtropical grass pollen allergens in allergic rhinitis patients

Objective

Globally, grass pollens (GP) are major aeroallergen triggers of allergic rhinitis (AR) and asthma. However, patterns of allergic sensitisation to pollen of temperate (Pooideae: Lolium perenne) and subtropical (Chloridoideae: Cynodon dactylon and Panicoideae: Paspalum notatum) subfamilies in diverse climates remain unclear. This study aims to evaluate the level of allergic sensitisation and IgE specificity for major GP allergens representing the three subfamilies in biogeographically distinct regions.

Methods

Participants (GP‐allergic with AR, 330; non‐atopic, 29; other allergies, 54) were recruited in subtropical: Queensland, and temperate: New South Wales, Western and South Australia, regions. Clinical history, skin prick test (SPT), total and specific IgE to GP and purified allergens (ImmunoCAP) were evaluated. Cross‐inhibition of sIgE with Pas n 1, Cyn d 1 and Lol p 1 by GP extracts was investigated.

Results

Queensland participants showed higher sensitisation to P. notatum and C. dactylon than L. perenne GP. sIgE was higher to Pas n 1 and Cyn d 1, and sIgE to Pas n 1 and Cyn d 1 was inhibited more by Panicoideae and Chloridoideae, respectively, than Pooideae GP. Conversely, participants from temperate regions showed highest sensitisation levels to L. perenne GP and Lol p 1, and sIgE to Lol p 1 was inhibited more by Pooideae than other GP.

Conclusion

Levels and patterns of sensitisation to subtropical and temperate GP in AR patients depended on biogeography. Knowledge of the specificity of sensitisation to local allergens is important for optimal diagnosis and choice of allergen‐specific immunotherapy to maximise benefit.

388 Bayou Beef: A random effects model of crustacean waste as a feedstock

It is important for researchers, as progressive producers, to consider human enterprise wastes as one of the next steps in feedstuff investigation. In an effort to reuse a seemingly useless and disposable component of one of America’s most enjoyed aquatic delicacies, our objective was to determine the nutritive value of crawfish and shrimp shells in relation to ruminant nutrition. These discarded items were collected from local events and sorted into four different groups: crawfish heads, crawfish tails, shrimp shells, and shrimp tails. Crawfish and shrimp wastes were tested independent of each other. These groups were dried at 55°C for 72 h and ground to pass through a 2-mm screen. Samples were subjected to a batch-culture in vitro true digestibility (IVTD) assay. A separate set of samples (1 mm) were assayed for dry matter, neutral detergent fiber (NDF), and acid detergent fiber (ADF), and acid detergent lignin (ADL; inclusive of residual ash). Data were analyzed as a completely randomized design using the MIXED procedure of SAS. Crawfish heads were assayed to contain 26.2% NDF, 13.4% ADF, and 1.0% ADL, while crawfish tails contained 23.7% NDF, 16.3% ADF, and 1.1% ADL. Crawfish heads and tails did not differ in IVTD (P = 0.48) or in vitro NDF digestibility (IVNDFD; P = 0.13; 76.7 vs. 77.2% and 86.8 vs. 91.0%, respectively). Shrimp shells contained 36.1% NDF, 26.9% ADF, and 4.1% ADL, whereas shrimp tails contained 29.1% NDF, 17.9% ADF, and 0.7% ADL. Shrimp tails had greater (P &lt; 0.01) IVTD (74.2 vs. 66.4%) but lesser (P = 0.01) IVNDFD than shrimp shells (80.6 vs. 85.0%). Results are interpreted to mean that crustacean waste may represent a suitable prospective feedstuff for further evaluation.

420 Case study: Educational outreach as a component of graduate education

Graduate students are developing skills in scientific communication, research, and various other specified trainings. However, adequate resources for these students are not always available at their home institution. Educational outreach programs are often discussed in relation to secondary education. The potential to expand these types of programs to the post-secondary and graduate levels of education would represent a potential benefit to the students, scientists, and universities involved in the exchange. In such programs, graduate students would participate in an exchange with other universities to address deficits introduced by a lack of resources. This educational experience in a new setting would allow exposure to techniques and ideals otherwise inaccessible to the student. The objective of this observational case study was to evaluate the relevance and value of graduate exchange as an educational outreach model in graduate education. In this case study, a graduate student from Tarleton State University’s Department of Animal Science and Veterinary Technology was supported to study for a period of three weeks in the University of Georgia’s Parasitology Laboratory. This exchange was established to teach in vitro techniques related to the student’s graduate research. The student was able to gain valuable experience in laboratory techniques that aided in personal and professional growth while also expanding the capabilities of the home institution through training exercises conducted on return to campus. In addition to expansion of research capacity, the student was able to serve as an ambassador for the home institution, thereby enabling a more fluid exchange of ideas through student recruitment. Qualitative results from this case study would indicate that similar educational outreach opportunities are valuable components of graduate education and serve as an example for development in future graduate programs.

PSXIV-29 Influence of prerequisite courses on performance of students in an animal nutrition course: A one-year summary

Anecdotes abound in departmental curriculum committees surrounding the purpose and necessity of prerequisite courses for major subjects. Some believe that a student should have as much exposure as possible to subject matter prior to attempting to gain a full understanding of the material. Others believe that prerequisite courses put an undue burden on students to take excessive coursework and that most of the students’ needs can be provided in a single course. The objective of this study was to ascertain the influence of prerequisite courses in animal science, biology, and chemistry on performance of students in an undergraduate animal science course. In the spring semester of 2019, students taking the animal nutrition course at Tarleton State University were enrolled in the experiment. On the second day of class, students were given a comprehensive exam resembling a final examination to assess knowledge on entry to the course. Subsequently, students completed an online survey to record demographics and educational background in relevant courses. Data were analyzed using PROC MIXED and PROC CORR of SAS v. 9.4. Females had an average score of 39 and males had an average score of 35 on the pre-test, but these numbers were statistically similar (P = 0.16). Student scores on the pre-tests were positively correlated the number of biology (r = 0.52; P &lt; 0.01) and chemistry (r = 0.46; P &lt; 0.01) courses taken, but showed no association (r = 0.14; P = 0.37) with the number of previous animal science courses. Similarly, the number of previously taken biology and chemistry courses were positively correlated (r = 0.70; P &lt; 0.01). Results are interpreted to mean that prior experience in biology and chemistry, but not animal science, are major factors for student performance in animal nutrition and should be considered for prerequisite courses.

PSIX-27 Moo-vie Snacks: Storage stability and nutritive value of waste popcorn as a feedstock

The use of by- or co-products in livestock production is not a novel concept. However, as adoption of a novel feed ingredient increases, the cost efficiency of its use generally decreases. Therefore, discovery of novel feed ingredients is a worthwhile academic pursuit. Our objective was to determine the storage stability of popcorn (Zea mays L.) in terms of gain or loss in nutritive value. Popcorn was collected on consecutive weekdays in two wk from a local cinema. Samples (n = 10) were subdivided into 9 aliquots and subjected to storage, uncovered, for 0, 1, 2, 3, 7, 35, 70, 105, and 140 d. Following the assigned storage time, samples were dried at 55°C to determine weight loss. Samples were dried at 55°C, ground to pass through a 2-mm screen, and subjected to a batch-culture in vitro assay for digestibility estimates [in vitro true digestibility (IVTD) and in vitro NDF digestibility (IVNDFD)]. Subsamples were ground to 1 mm assayed for neutral detergent fiber and acid detergent fiber. There was a linear increase (P &lt; 0.01) in weight following open storage which was attributed to absorption of ambient moisture. There was a linear decrease (P = 0.03) in NDF, with values decreasing from 20.2% at d 0 to 16.6% at d 140. However, there was no effect of storage on ADF (P = 0.29), IVTD (P = 0.38), or IVNDFD (P = 0.37). Results are interpreted to mean that waste popcorn is relatively shelf stable and may be a viable candidate as a feedstock for diet formulation.

406 Reduce Reuse Rerumen: Reduction of Eschericia coli, coliform bacteria, Enterobacteriaceae, and yeast and mold colonies in dried paunch manure

The discovery of novel by-product feeds for animals, especially cattle, supports an economically viable agricultural community and enhanced stability in the United States food chain. By-products of livestock processing (in this case, paunch manure, or rumen content) could provide the tools necessary to achieve this goal. Paunch manure, the material from ruminant stomachs at the time of harvest, is a waste product of the meat industry and represents a final loss due to cost of disposal. Our objective in this study was to determine the microbial content of fresh versus dried paunch manure in an effort to assess viability as a potential feed source. Fresh paunch manure was collected from cattle at a local abattoir and immediately homogenized for microbial plating. One milliliter of decanted paunch manure was plated on specialized film for determination of colony counts from Enterobacteriaceae, coliform-forming bacteria, Eschericia coli, Salmonella, and yeast and mold. Plates were incubated at 36°C for 24 ± 2 hours. Data were analyzed as a random effects model using PROC MIXED of SAS v. 9.4. In the wet paunch, E. coli had a mean colony count of 3, coliform bacteria of 53, yeast and mold of 0, and Enterobacteriaceae were too numerous to count. In the dry paunch, E. coli had a mean colony count of less than 1, coliform bacteria of 52, yeast and mold of 0, and Enterobacteriaceae less than 1. Source of paunch contributed a majority to the total variance in all instances of the random effects models. Results are interpreted to mean that, given the drastic reduction in microbial loads, paunch manure may represent a viable feedstock for further testing and development.

419 Academic performance and views toward community service from students engaged in service learning through a beef production course

Experiential learning is a feature common to post-secondary agricultural education. Similar to experiential learning opportunities, incorporation of service learning into post-secondary coursework is being encouraged more often. Our objective was to determine how community engagement and introduction of real-world problems in a species-specific production course would affect student performance and outlooks on community service. This experiment was conducted as a completely randomized design within the beef cattle production class during the spring 2019 semester at Tarleton State University. Thirty-eight students were enrolled in the course across two laboratory sections. Students in the first laboratory section were used as a control group. In the control, students were asked to draw from a selection of possibilities a description of herd size, sire and dam breed type, and county. Groups were asked to develop a management plan for a commercial cow-calf operation. Students in the second laboratory section were asked to brainstorm the most prevalent barriers to implementation of best management practices in cow-calf production. Groups were randomly assigned to each topic and were tasked with developing a tri-fold brochure addressing the barrier. They were instructed that this was being done as a service to the greater beef community and would be evaluated by industry representatives. Students in CON had more (P &lt; 0.05) students that reported performing community service weekly or monthly prior to the study than TRT. Groups were similar (P ≥ 0.41) in their assessment of community needs and the role of college students in community service. Likewise, CON and TRT had similar (P ≥ 0.41) responses in having less time available for coursework and their service contributing to the betterment of the overall community. Results are interpreted to mean that incorporation of service learning opportunities does not influence student views on community service.

PSIII-28 Kibbles ‘n Conjecture: A corollary analysis of ingredient composition, price, and nutritive value of commercial dog food

Quality nutrition for canine species contributes to a large global economic and health care field. Choices abound in terms of the availability of food in any given retail outlet. Likewise, there is copious conjecture surrounding the supposed benefits of certain brands or types over others, especially in the choice of conventional versus grain-free food types. A comparison of nutritive value of feeds relative to ingredient formulation and consumer cost would provide useful insight to the consumer when making selections for canine companion animals. This study sought to ascertain the correlations among ingredient position, nutritive value, and cost of commercially-available dog food. Over the course of February and March of 2019, commercially-available dog food was evaluated at local retail outlets in Stephenville, TX. For each observation, records were made of brand name, formulation, ingredient list, guaranteed nutritive analysis, and cost. Pearson’s correlation coefficients were calculated using PROC CORR, and effect of conventional versus grain-free claims on cost and nutritive value were analyzed using PROC MIXED of SAS v. 9.4. Order in which meat, meat meal, or corn occurred in the ingredient list was not statistically correlated to cost per kg (P ≥ 0.33) or concentrations of crude protein (P ≥ 0.35), crude fat (P ≥ 0.13), or crude fiber (P ≥ 0.35). Grain-free formulations cost significantly more than conventional formulations ($2.70 vs. $4.60/kg; P &lt; 0.01). However, there was no effect of formulation on concentrations of crude protein (P = 0.07), crude fat (P = 0.37), or crude fiber (P = 0.44). Results are interpreted to mean that, despite claims to the contrary, order of ingredients in a formulation have no observable effect on the nutritive value, but large effects on cost, of commercially-available dog food.

2712. Safety and Immunogenicity of two Doses of ExPEC4V Vaccine Against Extraintestinal Pathogenic Escherichia coli Disease in Healthy Adult Participants

Background

The ExPEC4V vaccine contains 4 Escherichia coli O-antigens (O1A, O2, O6A, O25B) conjugated to exotoxin protein A and is being studied for prevention of Invasive Extraintestinal pathogenic E. coli (ExPEC) Disease (IED). This phase-2 double-blind study assessed safety and immunogenicity of ExPEC4V Clinical Trial Material (CTM), manufactured via a redesigned process (optimized O1A strain).

Methods

Participants (≥18 years) in stable health were randomized (3:1) to receive ExPEC4V dose 4:4:4:8 μg PS/serotype or placebo on Day 1 and second vaccination on Day 181 (6 months after first vaccination). Participants will be followed for safety until end of study at Day 360. Reactogenicity and immunogenicity (by ELISA, opsonophagocytic killing [OPA] assays) were evaluated pre-vaccination, and 15 days after first and second vaccinations (Day 195).

Results

Of 100 participants randomized (mean age 56, 48% males) and vaccinated (ExPEC4V, n = 75; placebo, n = 25), 97 completed Day 30. Solicited local AEs were higher for ExPEC4V (38.7%) than placebo (20%); most frequent was pain/tenderness (38.7% vs 20%). Solicited systemic AEs were higher in ExPEC4V (49.3%) than placebo (20%); most frequent was fatigue (32% vs. 12%). No serious or grade 3 solicited local AEs were reported. One participant in ExPEC4V experienced a grade 3 solicited systemic fatigue considered vaccine-related by investigator. ExPEC4V demonstrated immune responses against all serotypes at Day 15. Geometric mean titer effective concentration rank by serotypes was O2 > O1A > O6 > O25B (Figures 1 and 2). At Day 15, ≥ 82% of participants in ExPEC4V and none in placebo had ≥2-fold increase from baseline of ELISA titer for all serotypes. In ExPEC4V, ≥47% had ≥2-fold increase from baseline of OPA titer for all serotypes, while 8% in placebo had ≥2-fold increase only for O6A. Good correlation was observed between ELISA and OPA across serotypes (r ≥ 0.76).

Conclusion

ExPEC4V elicited robust and functional immune responses across all serotypes and was well tolerated with no vaccine safety findings. This study supports the development of future multivalent ExPEC vaccine to prevent IED.

Disclosures

All authors: No reported disclosures.

9 Reduce Reuse ReRumen: Variability in nutritive value of paunch manure

Ruminant animals develop a diverse and complex microbial ecosystem for digesting fibrous feedstuffs, but this material represents a cost to the industry when bound for rendering at harvest. Our objective was to determine the feed value of paunch manure recovered from an abattoir. Twelve paunch samples were collected from slaughtered cattle at the Tarleton State University Meat Laboratory, Stephenville, TX. Samples were dried under forced air at 55°C to a constant weight and ground to pass through 2-mm screen. A subsample was ground to 1-mm and assayed for DM, CP, and sequential NDF and ADF. Physically effective fiber (peNDF) was calculated with 2 L of unground, dried at 55 ˚C, paunch material using the manually-operated Penn State Particle Separator. Paunch peNDF was determined by multiplying the physical effectiveness factor by the total NDF content of the sample. Samples (2-mm) were subject to batch culture in vitro digestibility assays for determination of digestibility coefficients. Data were analysed as a random effects model using PROC GLIMMIX in SAS. Neutral detergent fiber, ADF, ADL, CP, and peNDF values were 68.1, 39.9, 10.9, 15.0, and 38.7%, respectively. Contribution to variance of the individual animal for NDF, ADF, ADL, CP, and peNDF was 97.2, 97.9, 95.4, 19.1, and 97.5%, respectively. In vitro true digestibility (IVTD) and in vitro neutral detergent fiber digestibility (IVNDFD) was recorded as 46.2% and 21.6%, respectively. Contribution to variance of the animal for IVTD and IVNDFD was 99.05 and 98.49%, respectively. Data collected suggest paunch manure could provide valuable nutrients for livestock production, specifically fiber and protein. For full viability of application in a sustainable system, a centralized receiving and compositing system may be useful for development of a consistent product.

80 Effectiveness of naturally sourced mixed tocopherols as an antioxidant when compared to Bha and Bht in fresh pork sausage

Fresh ground pork products are highly susceptible to deteriorative oxidation due to high fat content and increased surface area exposure of proteins. Recent trends and health concerns among consumers have sparked interest in finding alternatives for synthetic ingredients used for preservation of commercially manufactured processed meats. The objective of this study was to compare the effectiveness of naturally sourced mixed tocopherols to a mixture of butylated hydroxylanisole (BHA) and butylated hydroxytoluene (BHT) on prevention of lipid oxidation and color stability in fresh pork sausage patties. Duplicate batches of pork Boston butt trim and pork back fat were mixed 5:1, respectively, coarse ground, and combined with pork sausage seasoning. Pork mixture was then fine ground and 3175.5 g portions were assigned to one of three treatments: no antioxidants (CON), 0.01% of BHA and 0.01% BHT mixture (SYN), or 0.03% Decanox MTS30P (MTS). Patties (56.7 g) were hand pressed, placed on Styrofoam trays (S4), polyvinyl chloride film overwrapped and positioned in a retail display case. Patties (n = 45) were evaluated for instrumental color (L*, a*, and b*) and display discoloration (1 = very bright, to 8 = tan to brown) in 12-hr intervals for 252 hr. Fifteen patties from each treatment were collected for thiobarbituric acid reactive substance analysis. No differences between treatments (P > 0.05) were found for display discoloration or instrumental color. SYN patties had significantly lower malondialdehyde values (P = 0.047) than both CON and MTS patties at 252 hr. In conclusion, mixed tocopherols were not as effective as synthetic antioxidants in slowing lipid oxidation. However, it can be noted that mixed tocopherols can replace synthetic antioxidants in ground pork sausage and have the same effect on color stability.

166 Moo-vie Snacks: Evaluation of waste popcorn as a feedstuff in comparison with known livestock feeds

While the use of by- or co-products can help offset the costs of feeding cattle, these feeds often increase in price with increased adoption. Therefore, discovery and characterization of novel feedstuffs could benefit the producer. Our objective was to evaluate the viability of waste popcorn (Zea mays L.) as a feedstuff in ruminant diets. This objective was addressed through a series of two experiments. In Exp. 1, storage stability of popcorn was evaluated. Popcorn was collected on consecutive weekdays in 2 wk from a local cinema. Samples (n = 10) were subdivided into 9 aliquots and subjected to storage, uncovered, for 0, 1, 2, 3, 7, 35, 70, 105, and 140 d. Following the assigned storage time, samples were dried at 55°C to determine weight loss. Following open storage in a laboratory at approximately 24°C, popcorn gained (P < 0.05) between 2.6% (3 d) and 5.6% (105 d) of the original weight through moisture absorption. When dried, however, samples from any length of storage were within 1% of the original weight (P < 0.05). In Exp. 2, a composite sample of popcorn was used in comparison with cracked and steam-flaked corn (Zea mays L.), popped milo [Sorghum bicolor (L.) Moench ssp. bicolor], and rolled barley (Hordeum vulgare L.). Samples were dried at 55°C, ground to pass through a 2-mm screen, and subjected to a batch-culture in vitro assay for digestibility estimates. In vitro true digestibility of popcorn (77.8%) was less (P < 0.05) than estimates for cracked corn (94.8%), popped milo (93.6%), steam-flaked corn (92.6%), or rolled barley (90.3%). From these results, we may conclude that, while popcorn is not as digestible as other commercial energy sources, it may represent a viable option in the arsenal of feed formulation.

190 Reduce Reuse ReRumen: Preservation method of rumen fluid collected from slaughtered cattle affects in vitro digestibility

Microbes and chemical constituents in the rumen fluid play an important role when re-establishing the rumen microbial population. Identification of a viable preservation method could have lasting implication of veterinary and research applications. Our objective was to determine the efficacy of preservation methods on rumen liquor. Twelve paunch samples were collected from slaughtered cattle at the Tarleton State University Meat Laboratory, Stephenville, TX. Rumen content was collected from different locations within the rumen, strained through eight layers of cheesecloth, and divided into five 500-mL aliquots. Aliquots were randomly allocated to one of five preservation methods (freezing or lyophilisation) and preservative (glycerol; yes or no). A fresh control was maintained from each sample. Three reference feeds and two roughage sources were used in the batch culture procedure. Reference feeds were dried to a constant weight at 55°C and ground to pass through a 2-mm screen. Ground samples were subjected to batch culture in vitro true digestibility (IVTD) assays using each of the four ruminal fluids (plus the control) for digestibility estimates. Original samples and incubated residues were assayed for DM, CP, NDF, and ADF. Data were analyzed in a 2 × 2 + 1 augmented factorial design using GLIMMIX procedure of SAS. There were no differences (P > 0.05) in IVTD when using protein or energy feeds; however, there were differences in IVTD for all treatments for fiber concentrates and forage reference feeds. Despite lower degradation of feeds when frozen or lyophilized rumen fluid was used, preserved rumen fluid may be a viable option in the absence of fresh inoculum for veterinary and research applications

168 Calf-inated Cups: Disposable coffee cups as a fiber source in ruminant diets

Per unit energy, fiber is among the most expensive components of the ruminant diet. Wastes from human enterprises may represent the next step in feedstuff investigation. In an effort to minimize the anthropogenic waste contribution, and as a means to find a more cost-efficient resource to feed ruminant animals, our objective was to determine the nutritive value of disposable coffee cups and warmer sleeves in relation to ruminant nutrition. Discarded cups and warmer sleeves were collected from employees at Tarleton State University in fall of 2017. Cups were obtained from five sources, and warmer sleeves were obtained from two sources. Cups and sleeves were dried at 55°C for 72 h and ground to pass through a 2-mm screen. Ground samples were subjected to a batch-culture in vitro true digestibility (IVTD) assay. Original samples and incubated residues were then assayed for DM, NDF, ADF, and CP. Data were analyzed as a random effects model completely randomized design using the MIXED procedure of SAS. There was no effect (P > 0.05) of source (n = 5) or type (cup or sleeve) for contribution to variance of NDF, ADF, IVTD, and in vitro NDF digestibility (IVNDFD). Mean values for NDF, ADF, IVTD, and IVNDFD across samples were 89.5, 81.4, 24.5, and 18.7%, respectively. Results indicate a low digestibility coefficient for these waste products, thus meaning its use as a feedstuff could be questionable. However, such results provide insight into niches where this product and other anthropogenic wastes may fit in the larger picture of ruminant nutrition

167 Livestock Literacy: Ensiling newspaper as a renewable fiber source for ruminant animals

Per unit energy, fiber is among the most expensive components of the ruminant diet. While the use of by- or co-products can help offset the costs of feeding cattle, these feeds often increase in price with increased adoption. Wastes from human enterprises may represent the next step in feedstuff investigation. Our objective was to evaluate the suitability of newspaper as a component of silage for ruminant feeding. Newspapers were obtained from the Dick Smith Library and JTAC News at Tarleton State University (Stephenville, TX). Samples were cut into strips (approximately 4.0 × 30.2 mm) using an office shredder. Sorghum-sudangrass [Sorghum bicolor (L.) Moench ssp. drummondii (Nees ex Steud.) de Wet & Harlan] was harvested and cut by hand to lengths of approximately 10 cm. Samples were combined to achieved DM ratios of 100:0, 75:25, 50:50, 25:75, and 0:100% newspaper and sorghum-sudangrass. Distilled water was added to achieve 45% DM. Samples were packed in a double layer of plastic sheeting and sealed in 19 L buckets. Laboratory silos were arranged in a Latin square design in a laboratory and allowed to ferment for 35 d. Ensiled samples were assayed for DM, particle size, and silage acids. There was no effect of newspaper percentage (P = 0.47) on silage pH. Ammonia (0.04 to 1.2% DM), total VFA (0.01 to 4.8% DM), lactic acid (0 to 46.6% VFA), and acetic acid (0.01 to 2.4% DM) increased linearly (P < 0.01) with increased concentration of sorghum-sudangrass. Results indicated that newspaper alone was not an effective feedstuff to ensile. However, addition of newspaper to grass silages could represent a viable means to decrease cost and extend resources for ruminant animal producers.

175 Reduce Reuse ReRumen: Variability in nutritive value of paunch manure

Ruminant animals develop a diverse and complex microbial ecosystem for digesting fibrous feedstuffs, but this material represents a cost to the industry when bound for rendering at harvest. Our objective was to determine the feed value of paunch manure recovered from an abattoir. Twelve paunch samples were collected from slaughtered cattle at the Tarleton State University Meat Laboratory, Stephenville, TX. Samples were dried under forced air at 55°C to a constant weight and ground to pass through 2-mm screen. A subsample was ground to 1-mm and assayed for DM, CP, and sequential NDF and ADF. Physically effective fiber (peNDF) was calculated with 2 L of unground, dried at 55 ˚C, paunch material using the manually-operated Penn State Particle Separator. Paunch peNDF was determined by multiplying the physical effectiveness factor by the total NDF content of the sample. Samples (2-mm) were subject to batch culture in vitro digestibility assays for determination of digestibility coefficients. Data were analysed as a random effects model using PROC GLIMMIX in SAS. Neutral detergent fiber, ADF, ADL, CP, and peNDF values were 68.1, 39.9, 10.9, 15.0, and 38.7%, respectively. Contribution to variance of the individual animal for NDF, ADF, ADL, CP, and peNDF was 97.2, 97.9, 95.4, 19.1, and 97.5%, respectively. In vitro true digestibility (IVTD) and in vitro neutral detergent fiber digestibility (IVNDFD) was recorded as 46.2% and 21.6%, respectively. Contribution to variance of the animal for IVTD and IVNDFD was 99.05 and 98.49%, respectively. Data collected suggest paunch manure could provide valuable nutrients for livestock production, specifically fiber and protein. For full viability of application in a sustainable system, a centralized receiving and compositing system may be useful for development of a consistent product.

113 Influence of cattle stress response to restraint method on artificial insemination pregnancy rates

Activation of physiological stress responses have been associated with decreased pregnancy rates in beef cattle. Therefore, alternative cattle restraint methods have been developed to reduce this negative impact. However, little evidence exists comparing pregnancy outcomes of differing methods. Thus our objective was to determine if a difference was present in pregnancy rate to fixed-time artificial insemination in Bos taurus beef females when using a breeding box (b) versus a squeeze chute (c). Cows and heifers from two separate locations (Virginia Tech University, VT; and R.A. Brown Ranch, RAB) were exposed to FTAI protocols at location of origin while restrained in a squeeze chute (n = 169) or a breeding box (n = 162). Females were exposed to the 7 day Co-Sync + CIDR protocol pre-breeding. At day of breeding, females were randomly assigned to treatment. Immediately following breeding, blood was collected via coccygeal venipuncture for assessment of plasma cortisol concentration using an automated ELISA assay (Immulite 2000 XPi, Siemens). Chute and Exit Score (1–5) were assessed at the time of breeding by a trained technician at each location. Pregnancy was verified thirty days post-breeding via rectal ultrasonography. Pregnancy rate (PROC FREQ) and cortisol (PROC GLIMMIX) were analyzed using SAS version 9.4. Also, a Linear Regression Model (SAS version 9.4) was used to determine relationships between chute score, exit score, and cortisol. It was found that there was no difference in pregnancy rate between the breeding box and the squeeze chute (61.73% vs 64.71%, P = 0.31, respectively). Cortisol showed no difference between b and c (59.44±10.17 vs 58.61±10.16, P = 0.68, respectively). There was no linear relationship between cortisol, exit score, and chute score (P = 0.14). It can be concluded that stress responses are similar between the breeding box and squeeze chute. Therefore females will have similar pregnancy rates when exposed to FTAI in either restraint mechanism.

A randomized, placebo-controlled trial of canakinumab in patients with peripheral artery disease

Extensive atherosclerotic plaque burden in the lower extremities often leads to symptomatic peripheral artery disease (PAD) including impaired walking performance and claudication. Interleukin-1β (IL-1β) may play an important pro-inflammatory role in the pathogenesis of this disease. Interruption of IL-1β signaling was hypothesized to decrease plaque progression in the leg macrovasculature and improve the mobility of patients with PAD with intermittent claudication. Thirty-eight patients (mean age 65 years; 71% male) with symptomatic PAD (confirmed by ankle-brachial index) were randomized 1:1 to receive canakinumab (150 mg subcutaneously) or placebo monthly for up to 12 months. The mean vessel wall area (by 3.0 T black-blood magnetic resonance imaging (MRI)) of the superficial femoral artery (SFA) was used to measure plaque volume. Mobility was assessed using the 6-minute walk test. Canakinumab was safe and well tolerated. Markers of systemic inflammation (interleukin-6 and high-sensitivity C-reactive protein) fell as early as 1 month after treatment. MRI (32 patients at 3 months; 21 patients at 12 months) showed no evidence of plaque progression in the SFA in either placebo-treated or canakinumab-treated patients. Although an exploratory endpoint, placebo-adjusted maximum and pain-free walking distance (58 m) improved as early as 3 months after treatment with canakinumab when compared with placebo. Although canakinumab did not alter plaque progression in the SFA, there is an early signal that it may improve maximum and pain-free walking distance in patients with symptomatic PAD. Larger studies aimed at this endpoint will be required to definitively demonstrate this. ClinicalTrials.gov Identifier: NCT01731990.

Adverse drug reaction classification by health professionals: appropriate discrimination between allergy and intolerance?

Background

The correct classification of an adverse drug reaction (ADR) as allergy (immunological) or intolerance (non-immunological) has important clinical implications. The aim of this study was to examine the ability of health professionals to discriminate between allergy and intolerance, classify the severity of the ADR and degree of contraindication.

Methods

Health professionals were presented ten ‘real-life’ ADR scenarios using an online questionnaire and asked to: categorise the reaction as allergy or intolerance, rate the severity of the reaction and judge the level of contraindication of the causative drug. The number and proportion of responses were calculated for each of the cases presented and associations between classification of reaction type, severity and level of contraindication were examined.

Results

A total of 394 responses were received. Overall 59.0% (SD 28.9) correctly categorised the cases, 60.8% (SD 16.8) classified the severity correct, and less than half (44.7%, SD 28.6) correctly identified the level of contraindication. The proportion of health professionals correctly answering the type, severity and level of contraindication for the allergy case was significantly higher (p < 0.0001) by comparison to the intolerance cases (type: 56.6% ± 33.1; severity: 57.3 ± 11.9; level of contraindication: 38.5 ± 19.9).

Conclusions

Health professionals have suboptimal understanding of classification of ADRs. Strategies are required to strictly avoid re-exposure of patients to drugs which carry an increased risk of inducing a dangerous reaction, whilst minimising the avoidance of drugs which are of minimal risk or allowing the use of low-risk drugs where the benefits may be significant.