Publications by authors named "Robert Larson"

Objective: To use a novel approach of targeted thoracic point-of-care ultrasound (TT-POCUS) of the caudodorsal right lung to determine potential associations between TT-POCUS measurements and the presence of interstitial pneumonia (IP) in feedyard cattle.

Methods: Cross-sectional study evaluated feedyard animals (n = 62; 358.4 ± 10.

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Objective: To evaluate a predictive model's ability to determine cattle mortality following first and second treatment for bovine respiratory disease and to understand the differences in net returns comparing predictive models to the status quo.

Methods: 2 boosted decision tree models were constructed, 1 using data known at first treatment and 1 with data known at second treatment. Then, the economic impact of each outcome (true positive, true negative, false positive, and false negative) was estimated using various market values to determine the net return per head of using the predictive model to determine which animals should be culled at treatment.

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Objectives: To measure the effect of routine vaccination on serum amyloid A (SAA) concentration in apparently healthy horses. We hypothesized that routine vaccination would increase SAA in healthy horses.

Animals: 21 apparently healthy client-owned horses and 15 Kansas State University College of Veterinary Medicine-owned horses.

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Metaphylactic antibiotic use in feeder cattle is a common practice to control respiratory disease. Antimicrobial stewardship is important to ensure continued efficacy and to protect animal welfare. The objective of this study is to identify characteristics of cohorts of cattle that had not received metaphylaxis that would have benefited economically from the use of metaphylaxis.

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Background: Current management of axillosubclavian deep venous thrombosis (DVT) often uses thrombolysis for the DVT, prompt first rib removal, and occasional venoplasty or stenting. Our institution has increasingly used anticoagulation alone followed by interval first rib resection. We sought to analyze the effectiveness of this simplified technique.

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Article Synopsis
  • Bovine respiratory disease (BRD) is a significant issue in feedyards, impacting animal health and the use of antibiotics.
  • The study aimed to examine the connection between nasopharyngeal microbiota and the patterns of antimicrobial resistance in cattle with BRD, comparing those that lived or died to healthy animals.
  • Results showed that while there were slight differences in bacterial diversity among the groups, the nasopharyngeal microbiota of animals that lived or died from BRD were relatively similar to those of non-BRD animals.
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Background: Together with clinical examination, surveillance duplex examination represents the Society of Vascular Surgery recommendations for follow-up after endovascular intervention on the superficial femoral artery (SFA) and popliteal arterial segments. Compliance with postprocedural follow-up remains challenging. To establish a postangioplasty physiologic baseline, our institution began obtaining immediate postprocedural surveillance studies following lower extremity arterial interventions.

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Respiratory disease continues to be the major cause of mortality in feedyard cattle, with bronchopneumonia (BP) and acute interstitial pneumonia (AIP) as the two most common syndromes. Recent studies described a combination of these pathological lesions with the presence of AIP in the caudodorsal lungs and BP in the cranioventral lungs of necropsied cattle. This pulmonary pathology has been described as bronchopneumonia with an interstitial pneumonia (BIP).

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Objective: To evaluate predictive model ability to determine whether an animal finished the feeding period using data known at first treatment for bovine respiratory disease (BRD). Additional comparisons evaluated the potential benefits of predictions by adding weather data, utilizing balancing techniques, and creating models for individual feedyards.

Animals: This retrospective study included animal, pen, and feedyard data from 12 US feedyards from 2016 to 2021.

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Background: Prevention of spread of Streptococcus equi subspecies equi (S. equi) after an outbreak is best accomplished by endoscopic lavage of the guttural pouch, with samples tested by culture and real time, quantitative polymerase chain reaction (qPCR). Disinfection of endoscopes must eliminate bacteria and DNA to avoid false diagnosis of carrier horses of S.

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Background: Thoracic endovascular aortic repair (TEVAR) involving the aortic arch may increase the opportunity for stroke owing to disruption of cerebral circulation and embolization. In this study, a systematic meta-analysis was performed to examine the impact of proximal landing zone location on stroke and 30-day mortality after TEVAR.

Methods: MEDLINE and Cochrane Library were searched for all original studies of TEVAR reporting outcomes of stroke or 30-day mortality for at least two adjacent proximal landing zones, based on the Ishimaru classification scheme.

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Objective: To evaluate the risk and timing of right heart failure (RHF) in feedlot cattle.

Animals: Study population consisted of 1,717,356 cattle (5,527 cohorts) in 13 US and Canadian feedlots. There were 1,336 RHF diagnosed at necropsy.

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Pulmonary disease is often associated with feedlot cattle mortality, and the most common syndromes include bronchopneumonia, acute interstitial pneumonia, and bronchopneumonia with an interstitial pneumonia. The study objective was to utilize gross necropsy and histopathology to determine the frequency of pulmonary lesions from three major syndromes and agreement between gross and histopathological diagnosis. A cross sectional, observational study was performed at six U.

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Bovine respiratory disease (BRD) is a frequent beef cattle syndrome. Improved understanding of the timing of BRD events, including subsequent deleterious outcomes, promotes efficient resource allocation. This study's objective was to determine differences in timing distributions of initial BRD treatments (Tx1), days to death after initial treatment (DTD), and days after arrival to fatal disease onset (FDO).

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Objective: Determine the association between bovine leukemia virus (BLV) status and fertility in beef cows. BLV-status was defined using 3 different testing strategies (ELISA-, quantitative polymerase chain reaction- [qPCR], and high proviral load [PVL]-status). Fertility was defined as the overall probability of pregnancy as well as the probability of becoming pregnant in the first 21 days of the breeding season.

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Bovine respiratory disease (BRD) and acute interstitial pneumonia (AIP) are the main reported respiratory syndromes (RSs) causing significant morbidity and mortality in feedlot cattle. Recently, bronchopneumonia with an interstitial pattern (BIP) was described as a concerning emerging feedlot lung disease. Necropsies are imperative to assist lung disease diagnosis and pinpoint feedlot management sectors that require improvement.

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Timing and magnitude of bovine respiratory disease (BRD) can impact intervention and overall economics of cattle on feed. Furthermore, there is a need to better describe when cattle are being treated for BRD. The first objective was to perform a cluster analysis on the temporal distributions of cumulative first treatment BRD from HIGH (≥15% of cattle received treated for BRD) and LOW cohorts (>0 and <15% of cattle received treated for BRD) to assess cohort-level timing (days on feed) of BRD first treatments.

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A stochastic, individual animal systems simulation model describing U.S. beef cow-calf production was developed and parameterized to match typical U.

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Background: Repositioning patients is a frequent task for healthcare workers causing substantial stress to the low back. Patient handling methodologies that reduce low back load should be used. Some studies have observed the effect of bed height on back forces using a limited range of heights.

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The Bezold-Jarisch reflex is a powerful inhibitory reflex initiated by activation of cardiopulmonary vagal nerves during myocardial ischemia, hemorrhage, and orthostatic stress leading to bradycardia, vasodilation, hypotension, and vasovagal syncope. This clinically relevant reflex has been studied by measuring heart rate (HR) and mean arterial pressure (MAP) responses to injections of a variety of chemical compounds. We hypothesized that reflex responses to different compounds vary due to differential activation of vagal afferent subtypes and/or variable coactivation of excitatory afferents.

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Background: Post endovascular aneurysm repair (EVAR), surveillance with computed tomography-aortography (CTA) remains the most common practice, per Society for Vascular Surgery (SVS) guidelines. Chronic exposure to both radiation and intravenous (IV) contrast has raised concerns about long-term CTA follow-up (FU). As we have selectively used ultrasound (US) as a sole modality for post-EVAR surveillance, we sought to review our outcomes in this subset of patients.

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Objective: Determine bovine leukemia virus (BLV) seroprevalence of adult female cattle in Eastern Kansas beef herds and the proviral load (PVL) of those cattle found to be ELISA positive.

Animals: Convenience sample of 2,845 cows from 44 beef herds.

Procedures: BLV serostatus was determined using an ELISA antibody test (gp-51; IDEXX).

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Bovine respiratory disease (BRD) is a frequent disease in feedlot cattle, but little is known on the role of pen housing conditions. The objective of this research is to use a retrospective analysis with data from 10 U.S.

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Purpose Of Review: Spinal cord injury (SCI) is one of the biggest complications in open and endovascular aortic repairs. Historically, cerebrospinal fluid drains (CSFD) have been one of the most effective modalities in reducing SCI and one of the most studied. CSFD placement also carries its' own set of procedural risks.

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Background: The Risk Analysis Index (RAI) frailty scoring system has recently undergone revision and external validation using the National Surgical Quality Improvement Program (NSQIP) database. We set forth to evaluate the association of RAI-rev ranges with outcomes following lower extremity surgical revascularization and verify equivalent applicability across genders.

Methods: All elective NSQIP Targeted Lower Extremity Open cases from 2015-2019 were divided by EMR-recorded gender.

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