Live Swine Research Articles

An antimicrobial blue light prototype device controls infected wounds in a preclinical porcine model.

We developed a translational prototype antimicrobial blue light (ABL) device for treating skin wounds with ABL. Partial-thickness surgical wounds were created in live swine, an animal whose skin is considered the most like human skin, then heavily contaminated and left untreated for 24 hours with methicillin-resistant Staphylococcus aureus (MRSA). ABL treatment stabilized and reduced MRSA infection by greater than four orders of magnitude (>99.99%; p<0.0001) compared with untreated wounds in the same animal, after only two daily treatments. These data support further development of such devices for controlling infection in skin wounds. ABL, with or without concomitant administration of negative pressure, antimicrobials, or photosensitizers, could play an important role in modern wound care by reducing the amount, duration, and cost of antibiotics needed, helping reduce AMR. No such device for treating human cutaneous wounds currently exists. This deserves further development and study.

Relationship between renal pelvis pressure and post-ureteroscopy infection in a live swine model.

To evaluate the relationship between renal pelvis pressure and infection after ureteroscopy, using a live swine model. In anaesthetised pigs, a 1-h ureteroscopy was performed using a pressure-sensing guidewire, with renal pelvis pressure maintained at either 37 mmHg or 75 mmHg for the entire procedure and infusion with saline alone or with a standardised concentration of uropathogenic Escherichia coli strain CFT073 (1.5 × 107 colony-forming units [CFU]/mL). Venous blood sampling was performed during and after the procedure. Vital signs, inflammatory biomarkers, and renal tissue and blood cultures were assessed. In 21 pig kidneys, study groups were: 37 mmHg with saline irrigation (n = 3); 75 mmHg with saline irrigation (n = 4); 37 mmHg with saline irrigation with 1.5 × 107 CFU/mL E. coli (n = 7); and 75 mmHg with saline irrigation with 1.5 × 107 CFU/mL E. coli (n = 7). Statistically significant changes in inflammatory biomarkers were most pronounced in the group with 75 mmHg saline irrigation + E. coli and were significantly elevated compared with the control group and the group receiving E. coli irrigation at 37 mmHg. Positive blood cultures were noted in 5/7 animals treated with E. coli at 75 mmHg; no others developed bacteraemia. In this swine model of ureteroscopy, irrigation with saline + E. coli at a renal pelvis pressure of 75 mmHg resulted in bacteraemia and inflammatory biomarker elevations significantly greater than both E. coli irrigation with renal pelvis pressure maintained at 37 mmHg and the control.

Behind Amor Blunt Trauma Lung and Liver Strains from Indenter Loading via Finite Element Modeling

Abstract To determine behind armor blunt trauma injury criteria, experiments have been conducted to launch projectiles at live swine at velocities ranging up to 65 m/s using one type of indenter design. To ensure the generalizability of the developed injury criteria, tests are needed with other indenter designs. The objectives of this study were to evaluate the kinematics and injury parameters from two indenter designs using human body finite element modeling. The simulation matrix consisted of indenter designs of chord and cylindrical shape, and 150 and 230 grams (g) mass, with impacts to liver and lung regions at 30 and 60 m/s. Rib and lung strains from lung impacts, and rib strains and liver strain energy densities from liver impacts were used to evaluate the design variables of mass and shape. Both designs played a role in skeletal and organ injury parameters. Analysis revealed the increased susceptibility for skeletal and organ traumas with the high mass indenter at high velocity impacts. The cylindrical indenter may be protective for organ injuries due to the larger area of loading on the ribcage compared to the chord indenter. Results from the chord indenter may serve as a conservative estimate of injury criteria.

Attenuated African swine fever viruses and the live vaccine candidates: a comprehensive review.

The African swine fever virus (ASFV) is spreading worldwide and causing huge economic losses to the global pig industry. The ASFV genome is 170-193 kb in length, contains approximately 150 open reading frames, and encodes more than 200 proteins, most of which have unknown functions. Owing to the unique viral structure, replication strategy, large number of genes of unknown function, and complicated pathogenesis, vaccine development research is challenging. Several naturally attenuated ASFV isolates have been extensively investigated and many genetically manipulated, gene-deleted, and cell-adapted ASFVs have been reported. Currently, live attenuated viruses prepared from weakly virulent strains are an efficient method to provide effective protection in vaccinated pigs; however, these have seldom been widely approved for vaccine use, except in Vietnam. Herein, we summarize the attenuated isolates or vaccine candidates for live vaccines derived from different sources, including naturally mutated, attenuated, cell-adapted, and genetically modified recombinant ASFVs. This will help to understand the gene function and immunogenicity of attenuated live ASFV, as well as the shortcomings of these viruses as vaccine candidates, and provide clues to prepare live, efficient, and safe vaccines for African swine fever.IMPORTANCEOutbreaks of African swine fever (ASF) have caused devastating losses to the global pig industry. Pigs immunized with ASFV attenuated virus can resist the lethal challenge of a strongly virulent virus. Here, we summarize the virulence of naturally mutated, cell-adapted, and genetically recombinant ASFV for pigs, and the protective effect after facing an attack challenge. We also analyze the advantages and disadvantages of ASFV attenuated viruses as vaccine candidates to provide clues for the preparation of efficient and safe live African swine fever vaccines.

A Pressure Sensing Device to Assist in Colonoscopic Procedures to Prevent Perforation-A Case Study.

Colonoscopy has a limited field of view because it relies solely on a small camera attached to the end of the scope and a screen displayed on a monitor. Consequently, the quality and safety of diagnosis and treatment depend on the experience and skills of the gastroenterologist. When a novice attempts to insert the colonoscope during the procedure, excessive pressure can sometimes be applied to the colon wall. This pressure can cause a medical accident known as colonic perforation, which the physician should prevent. We propose an assisting device that senses the pressure applied to the colon wall, analyzes the risk of perforation, and warns the physician in real time. Flexible pressure sensors are attached to the surface of the colonoscope shaft. These sensors measure pressure signals during a colonoscopy procedure. A simple signal processor is used to collect and process the pressure signals. In the experiment, a colonoscope equipped with the proposed device was inserted into a simulated colon made from a colon extracted from a pig. The processed data were visually communicated to the gastroenterologist via displays and light-emitting diodes (LEDs). The device helps the physician continuously monitor and prevent excessive pressure on the colon wall. In this experiment, the device appropriately generated and delivered warnings to help the physicians prevent colonic perforation. In the future, the device is to be improved, and more experiments will be performed in live swine models or humans to confirm its efficacy and safety.

Behind Armor Blunt Trauma: Liver Injuries Using a Live Animal Model.

While the 44-mm clay penetration criterion was developed in the 1970s for soft body armor applications, and the researchers acknowledged the need to conduct additional tests, the same behind the armor blunt trauma displacement limit is used for both soft and hard body armor evaluations and design considerations. Because the human thoraco-abdominal contents are heterogeneous, have different skeletal coverage, and have different functional requirements, the same level of penetration limit does not imply the same level of protection. It is important to determine the regional responses of different thoraco-abdominal organs to better describe human tolerance and improve the current behind armor blunt trauma standard. The purpose of this study was to report on the methods, procedures, and data collected from swine. Live swine tests were conducted after obtaining approvals from the local institution and the Army Care and Use Review Office of the U.S. Department of Defense. Trachea tubes and an intravenous line were introduced before administering anesthesia. Pressure transducers were inserted into the lungs and aorta. An indenter simulating the backface deformation profiles produced by body armor from military-relevant ballistics to human cadavers was used to deliver impact loading to the liver region. A triaxial accelerometer was included in the indenter design. The animals were monitored for 6 hours, necropsies were performed, and injuries were identified. Biomechanical data of the energy, velocity, deflection, viscous criterion, force, and impulse variables were obtained for each test. Peak accelerations, velocities, deflections, forces, impulse, and energies ranged from 897 to 5,808 g, 21 to 59 m/s, 1.96 to 8.87 cm, 2.3 to 13.1 kN, 1.1 to 7.1 Ns, and 58 to 387 J, respectively. The peak viscous criterion ranged from 0.8 to 5.8 m/s. All animals survived the 6-hour survival period. Three animals responded with liver lacerations while the remaining 4 did not have any injuries. The experimental design based on parallel tests with whole body human cadavers and cadaver swine was found to be successful in delivering controlled impacts to the liver region of live swine and reproducing liver injuries. Previously used biomechanical measures as potential candidates for injury criteria development were obtained. Using this proven model, tests with additional samples are needed to develop injury risk curves for liver impacts and obtain regional (liver) injury criteria.

Analysis of Injury Metrics From Experimental Cardiac Injuries From Behind Armor Blunt Trauma Using Live Swine Tests: A Pilot Study.

Warfighters are issued hard body armor designed to defeat ballistic projectiles. The resulting backface deformation can injure different thoracoabdominal organs. Developed over decades ago, the behind armor blunt impact criterion of maximum 44 mm depth in clay continues to be used independent of armor type or impact location on the thoracoabdominal region covered by the armor. Because thoracoabdominal components have different energy absorption capabilities, their mode of failures and mechanical properties are different. These considerations underscore the lack of effectiveness of using the single standard to cover all thoracoabdominal components to represent the same level of injury risk. The objective of this pilot study is to conduct cardiac impact tests with a live animal model and analyze biomechanical injury candidate metrics for behind armor blunt trauma applications. Live swine tests were conducted after obtaining approvals from the U.S. DoD. Trachea tubes. An intravenous line were introduced into the swine before administering anesthesia. Pressure transducers were inserted into lungs and aorta. An indenter simulating backface deformation profiles produced by body armor from military-relevant ballistics to human cadavers delivered impact to the heart region. The approved test protocol included 6-hour monitoring and necropsies. Indenter accelerometer signals were processed to compute the velocity and deflection, and their peak magnitudes were obtained. The deflection-time signal was normalized with respect to chest depth along the impact axis. The peak magnitude of the viscous criterion, kinetic energy, force, momentum and stiffness were obtained. Out of the 8 specimens, 2 were sham controls. The mean total body mass and soft tissue thickness at the impact site were 81.1 ± 4.1 kg and 3.8 ± 1.1 cm. The peak velocities ranged from 30 to 59 m/s, normalized deflections ranged from 15 to 21%, and energies ranged from 105 to 407 J. The range in momentum and stiffness were 7.0 to 13.9 kg-m/s and 22.3 to 79.9 N/m. The maximum forces and impulse data ranged from 2.9 to 11.7 kN and 1.9 to 5.8 N-s. The peak viscous criterion ranged from 2.0 to 5.3 m/s. One animal did not sustain any injuries, 2 had cardiac injuries, and others had lung and skeletal injuries. The present study applied blunt impact loads to the live swine cardiac region and determined potential candidate injury metrics for characterization. The sample size of 6 swine produced injuries ranging from none to pure skeletal to pure organ trauma. The viscous criterion metric associated with the response of the animal demonstrated a differing pattern than other variables with increasing velocity. These findings demonstrate that our live animal experimental design can be effectively used with testing additional samples to develop behind armor blunt injury criteria for cardiac trauma in the form of risk curves. Injury criteria obtained for cardiac trauma can be used to enhance the effectiveness of the body armor, reduce morbidity and mortality, and improve warfighter readiness in combat operations.

Matched-pair hybrid test paradigm for behind armor blunt trauma using an experimental animal model

BackgroundThe current behind armor blunt trauma (BABT) injury criterion uses a single penetration limit of 44 mm in Roma Plastilina clay and is not specific to thoracoabdominal regions. However, different...

Development of a contrast-enhanced ultrasound guided high intensity focused ultrasound system for coagulation of liver parenchyma.

The liver is the most common organ injured in blunt abdominal trauma and makes up roughly 5% of all trauma admissions. Current treatments are invasive and resource-intensive, which may delay care. We aim to develop and validate a contrast-enhanced ultrasound (CEUS)guided noninvasive tool to treat liver lacerations at the bedside. Two 1.8 MHz high-intensity focused ultrasound (HIFU) elements were coupled to a C1-6 diagnostic ultrasound probe and a Logiq E10 scanner (GE HealthCare) utilizing a custom enclosure for co-registered imaging and ablation. A phantom was created from polyacrylamide gel combined with thermochromic ink whose color changes above biological ablative temperatures (60 °C). The HIFU wave was focused approximately 0.5 cm below the surface utilizing a 50% duty cycle generating 11.9 MPa for 20, 30, 40, 50, and 60s. Experiments were repeated on ex vivo chicken livers in a water bath. Finally, the livers of 4 live swine underwent up to 6 CEUS-guided treatments using parameters optimized from in vitro work. Treatment of the phantom between 20-60s, produced ablation sizes from 0.016 to 0.4 cm 3 . The relationship between time and size was exponential (R 2 = 0.992). Ablation areas were also well visualized on with ultrasound imaging. The ex vivo liver ablation size at 20s was 0.37 cm 3 , at 30s was 0.66 cm 3 , and at 100 s was 5.0 cm 3 . For the in-vivo swine experiments, the average ablation area measured 2.0x0.75 cm with a maximum of 3.5x1.5 cm. CEUS was utilized with the contrast agent Definity (Lantheus) for identification of lacerations as well as immediate post operative evaluation of therapy. These experiments demonstrate the feasibility of CEUS guided transdermal HIFU ablation and the time-dependent size of ablation. This work warrants future investigations into using ultrasound to detect active bleeding and HIFU to coagulate grade III and IV liver laceration. Therapeutic/care management.

A Pilot Study Testing the Novel Use of a Snake Bite Compression Device for Field Hemostasis and Wound Repair in an Animal Model.

A commercially available snake bite device was pilot tested for novel use as a method of hemostasis and wound repair at a noncompressible site in a live swine model. The device is light, is plastic, uses a hook-and-loop strap attachment, and is easily deployed. The device could offer a method for the field repair of an actively bleeding laceration at a noncompressible site in an austere environment. This was an interventional, prospective, controlled study in a large animal model. The study was approved by the Rhode Island Hospital Institutional Review Board (IRB) and the Animal Welfare Committee/Institutional Animal Care and Use Committee and the Lifespan Research Conflict of Interest Committee. Each animal acted as its own control. Blood loss was measured and compared between repairs of standardized incisions with and without the device's application. The lacerations were sutured closed. Two proceduralists alternated tasks of wound repair versus blood collection. Blood loss was measured by using gauze sponges to capture the blood during a 30-second free-bleeding period and during the repair itself. Using a one sample t-test (the expected difference in blood loss between the two incision repair methods = 0 if the null hypothesis were true), we calculated the mean difference in the deltas between the repair methods. The mean delta difference was 3.1 g (SE ± 0.97). The t-test demonstrated that there was a significantly greater blood loss during the standard repair method, t(9) = 3.11, P < 0.01 than during the repair with the device in place (see Fig.2). A statistical power analysis conducted showed that with a sample size of 10 animals, there was sufficient statistical power to detect this significant effect (β = 0.82, α < 0.05, one-tailed). There was statistically significantly less blood loss during the repairs with the device's application. This feasibility experiment demonstrates that a commercially available snakebite device may be useful for hemostasis during laceration repair at anatomic sites not amenable to application of tourniquets or compressive dressings. Strengths of the study include the prospective controlled design, including the use of each animal as its own control; alternating proceduralists to account for any variability in suturing efficiency; and the statistical significance of the results despite the small number of subjects. One weakness is that the time required for each repair was not measured. The device's portability and reusability suggest applicability in austere medical environments. Future studies could include timing the repairs, using a skin stapler or wound adhesive instead of sutures, applying a hemostatic agent before the repair, and sequentially applying the device to wounds longer than the device.

3D Position Tracking Using On-Chip Magnetic Sensing in Image-Guided Navigation Bronchoscopy.

This paper presents a compact and low-cost on-chip sensor and readout circuit. The sensor achieves high-resolution 5-degrees-of-freedom (DoF) tracking (x, y, z, yaw, and pitch). With the help of an external wire wound sensor, it can also achieve high-resolution 6-degrees-of-freedom (DoF) tracking (x, y, z, yaw, pitch, and roll angles). The sensor uses low-frequency magnetic fields to detect the position and orientation of instruments, providing a viable alternative to using X-rays in image-guided surgery. To measure the local magnetic field, a highly miniaturised on-chip magnetic sensor capable of sensing the magnetic field has been developed incorporating an on-chip magnetic sensor coil, analog-front end, continuous-time ∆Σ analog-to-digital converter (ADC), LVDS transmitter, bandgap reference, and voltage regulator. The microchip is fabricated using 65 nm CMOS technology and occupies an area of 1.06 mm 2, the smallest reported among similar designs to the best of our knowledge. The 5-DoF system accurately navigates with a precision of 1.1 mm within the volume-of-interest (VOI) of 15 ×15 ×15 cm 3. The 6-DoF system achieves a navigation accuracy of 0.8 mm and an angular error of 1.1 degrees in the same VOI. These results were obtained at a 20 Hz update rate in benchtop characterisation. The prototype sensor demonstrates accurate position tracking in real-life pre-clinical in-vivo settings within the porcine lung of a live swine, achieving a reported worst-case registration accuracy of 5.8 mm.

Comparison of transseptal puncture using a dedicated RF wire versus a mechanical needle with and without electrification in an animal model.

Mechanical force to achieve transseptal puncture (TSP) using a standard needle may lead to overshooting and injury, and can potentially be avoided using a radiofrequency (RF)-powered needle or wire. Applying electrocautery to needles and guidewires as an alternative to purpose-built RF systems has been associated with safety risks, such as tissue coring and thermal damage. The commercially available AcQCross needle-dilator system (Medtronic) features a sharp open-ended needle for mechanical puncture, as well as a built-in connector to enable energy delivery for RF puncture. This investigation compares the safety and efficacy of the AcQCross needle to the dedicated VersaCross RF wire system and generator (Baylis Medical/Boston Scientific). In an ex vivo porcine model, VersaCross wire punctures were performed using 1 s, constant mode (approx. 10 W) with maximum two attempts. AcQCross punctures were performed by applying energy for 2 s using a standard electrosurgical generator at 10 W (max. five attempts), 20 W (max. two attempts), and 30 W (max. two attempts). Efficacy was assessed in terms of puncture success and a number of energy applications required for TSP. Safety was assessed quantitatively as force required for TSP, energy required to puncture, and incidence of tissue coring, as well as by qualitative assessment of puncture sites. Additional qualitative observation of tissue cores and debris were obtained from TSP performed in live swine. RF TSP was 100% successful using the VersaCross wire with 1.0 ± 0.0 attempts. When power was used with the AcQCross needle, it failed to puncture at low (10 and 20 W) power settings; TSP was achieved with 30 W of energy with 91% success using 1.53 ± 0.51 attempts (p < .05 vs. VC) with greater variability (F1,33 = 9223.5, p < .0001). Compared to RF puncture using the VersaCross system, mechanical puncture, alone, using the AcQcross needle required six times more force (8 mm additional forward device displacement) to perforate the septum. Qualitative assessment of puncture sites revealed larger defects and more tissue charring with the AcQCross needle at 30 W compared to punctures with VersaCross wire. Tissue coring with the open-ended AcQCross needle was observed in vivo and measured to occur in 57% of punctures using the ex vivo model; no coring was observed with the closed-tip VersaCross wire. The AcQCross needle frequently required higher energy of 30 W to achieve RF TSP and was associated with tissue coring and charring, which have been, previously, reported when electrifying a standard open-ended mechanical needle or guidewire. These findings may limit safety and effectiveness compared to the VersaCross system.

Estimating backfat depth, loin depth, and intramuscular fat percentage from ultrasound images in swine.

Fast, accurate, and reliable estimates of backfat depth, loin depth, and intramuscular fat percentage in swine breeding stock are used to increase genetic improvement and farm profitability. The objective of this study was to develop an equation-based model for the estimation of swine backfat depth, loin depth, and intramuscular fat percentage estimates obtained from longitudinal ultrasound images. Images were collected from purebred Duroc (n=230), purebred Large White (n=154), and commercial (n=190) pigs born in January 2021 at three farms located in North Carolina. An Exapad ultrasound machine captured longitudinal images across the 10th to 13th ribs at 182 (±12.8 SD) days of pig age. The total number of images processed for Duroc, Large White, and commercial pigs was 1385, 928, and 1168 images, respectively. To establish a standard measurement for model comparison, trained personnel following standard company procedures using the BioSoft Toolbox (v4.0.1.2; Biotronics Inc., Ames, IA) obtained backfat and loin depth measurements from the images. Longissimus muscle intramuscular fat percentage was predicted using near-infrared spectroscopy at approximately 22h postmortem. Backfat and loin depth estimation were conducted only for commercial pigs (n=190) while intramuscular fat estimation was conducted on all pigs (n=574). Average backfat depth, loin depth, and intramuscular fat percentage were 14.6 (±2.6 SD) mm, 63.7 (±5.5 SD) mm, and 2.21 (±0.82 SD) %. Image analysis and estimation model development were conducted in MATLAB R2021a. Edge detection via the image gradient was applied to segment ultrasound images into backfat, loin, and rib regions. Segmented images were used to estimate backfat depth, loin depth, and loin intramuscular fat percentage. After image quality control and filtering, the image inclusion rate for each breed-trait combination ranged from 76 to 97%. All Duroc and commercial pigs and 97% of Large White pigs were represented by at least one image for trait estimation. Coefficient of determination of models for the estimation of backfat depth, loin depth, and intramuscular fat percentage were 0.58, 0.57, and 0.56, respectively. Root mean square error of backfat depth, loin depth, and intramuscular fat estimation were 1.65mm, 3.58mm, and 0.54%, respectively. Results demonstrate the feasibility of using ultrasound image gradient and an equation-based approach to estimate swine backfat and loin depth, and intramuscular fat percentage. This equation-based approach to estimate carcass traits in live swine can enhance genetic improvement.

Flexible instrument with contact-aided structure and force feedback for endoscopic surgery.

Robot-assisted surgery can effectively reduce the difficulty and improve the success rate of the surgeries. However, currently available flexible instruments have several limitations, such as large size, few degrees of freedom, and lack of contact force perception. This study proposes a master-slave flexible instrument capable of force feedback. The instrument has a maximum outer diameter of 3mm and an overall length of 1200mm. With the internal working channel unoccupied, a three-dimensional force sensing unit is designed based on the neural network. The corresponding master-slave control method with proportional force feedback was also designed to effectively control the instrument. To verify the effectiveness of the system, in vitro and in vivo experiments were conducted. The corresponding tasks were successfully completed. The animal trial conducted in the digestive tract of a live swine proved that the system has the potential for clinical use.

Detection of resistance and virulence plasmids in Campylobacter coli and Campylobacter jejuni isolated from North Carolina food animal production, 2018–2019

Campylobacter remains the leading cause of bacterial foodborne illness in the U.S. and worldwide. Campylobacter plasmids may play a significant role in antimicrobial resistance (AMR) and virulence factor distribution, and potentially drive rapid adaptation. C. coli (n = 345) and C. jejuni (n = 199) isolates collected from live cattle, swine, turkey, and chickens, poultry carcasses at production, and retail meat in N.C. were analyzed to determine plasmid prevalence, extrachromosomal virulence and AMR genes, and the phylogeny of assembled plasmids. Putative plasmids ranging from <2 kb to 237kb were identified with virulence factors present in 66.1% (228/345) C. coli and 88.4% (176/199) C. jejuni plasmids (promoting adherence, invasion, exotoxin production, immune modulation, chemotaxis, mobility, and the type IV secretion system). AMR genes were identified in 21.2% (73/345) C. coli and 28.1% C. jejuni plasmids (conferring resistance to tetracyclines, aminoglycosides, beta-lactams, nucleosides, and lincosamides). Megaplasmids (>100 kb) were present in 25.7% (140/544) of the isolates and carried genes previously recognized to be involved with interspecies recombination. Our study highlights the extensive distribution and diversity of Campylobacter plasmids in food animal production and their role in the dissemination of biomedically important genes. Characterizing Campylobacter plasmids within the food animal production niche is important to understanding the epidemiology of potential emerging strains.

Ultrasound Assisted Endoscopic Gastric Bypass (USA-EGB): a potential endoscopic alternative to surgical bypass, a pre-clinical proof of concept study.

Background and study aims Endoscopic weight loss procedures have gained traction as minimally invasive options for the primary treatment of obesity. Thus far, we have developed endoscopic procedures that reliably address gastric restriction but result in significantly less weight loss than surgical gastrointestinal bypass. The goal of this nonsurvival study was to assess the technical feasibility of an endoscopic procedure, that incorporates both gastric restriction and potentially reversible gastrointestinal bypass. Methods Ultrasound-assisted endoscopic gastric bypass (USA-EGB) was performed in three consecutive live swine, followed by euthanasia and necropsy. Procedure steps were: 1) balloon-assisted enteroscopy that determines the length of the bypassed limb; 2) endoscopic ultrasound-guided gastroenterostomy that creates a gastrointestinal anastomosis using a lumen apposing metal stent; 3) endoscopic pyloric exclusion that disrupts transpyloric continuity resulting in complete gastrointestinal bypass; and 4) gastric restriction that reduces gastric volume. Results Complete gastrointestinal bypass and gastric restriction was achieved in all three swine. The mean total procedure time was 131 minutes (range 113-143), mean length of the bypassed limb was 92.5 cm and 180 cm, using short and long overtubes, respectively. There were no significant complications. Conclusions We successfully described USA-EGB in three consecutive live swine. Further studies are needed to access the procedures safety, efficacy, and clinical use.

Methicillin-resistant and methicillin-sensitive Staphylococcus aureus in pork industry workers, Catalonia, Spain

BackgroundMethicillin-resistant S. aureus (MRSA) especially ST398, is a zoonotic agent. This study aimed to determine the prevalence of methicillin-susceptible S. aureus (MSSA) and MRSA among workers in the pork production chain. Methods659 workers associated with 123 pig farms, livestock transporters, one pig slaughterhouse, pork transporters and 23 pork butcheries were studied for S. aureus recovery, and all isolates were characterized (antibiotic resistance, MLST and spa-typing). ResultsThe prevalence of S. aureus was 35.5%, 75.6% of isolates being MRSA. The prevalence of MRSA was 68.7% (149/217) among pig farm, 33.9% (19/56) livestock transporters, 2.9% (9/306) slaughterhouse, 0% in pork transporters (0/36) and butchery workers (0/44). Of the 234 S. aureus-positive workers, 100% (149/149) of pig farm workers, 82.6% (19/23) of livestock transporters, and 16.4% (9/55) of slaughterhouse workers carried MRSA isolates (p < 0.001). Of the workers who had contact with live swine, 61.8% (178/288) were S. aureus-positive, MRSA being detected in 96.1% of cases (p < 0.001). The most frequent lineage among MRSA were: ST398 (97.7%; 173/177) and ST1 (1.7%; 3/177); and among MSSA were ST30 (19.2%; 11/57) and ST5 (10.5%; 6/57). The most frequent spa-types among MRSA were t011 (93.8%, 166/177) and t1451 (2.25%, 4/177), and among MSSA: t084 (10.5%, 6/57) and t021 (7.0%, 4/57). All MRSA isolates showed resistance to tetracycline, 92.7% to clindamycin, 81.9% to erythromycin and 40.1% to cotrimoxazole. ConclusionsPig industry workers having occupational contact with live animals present a high risk of colonization of MRSA, especially by MRSA-ST398. Prevention measures should be intensified in any employment sector involving live animals.

Brief Review of Japanese Encephalitis Virus: Recommendations Related to North Carolina Swine Farms and Wider Implications for Swine Farming

Japanese encephalitis virus (JEV) is a mosquito-borne virus primarily found in Asia and Australia and is one of the few with an associated human/animal vaccine. Swine are amplifying hosts and wading birds are reservoirs of JEV, while horses and humans are incidental hosts. The primary vector is Culex tritaeniorhynchus, a generalist blood feeder not found in the United States (US); secondary vectors (e.g., Cx. pipiens, Cx. quinquefasciatus, Aedes japonicus, Ae. vexans) are widespread in the US (including North Carolina [NC]). The risk of JEV to NC was investigated because of widespread swine production, human populations, bird hosts, and possible mosquito vectors; however, recommendations can also apply to other swine producing states and regions. A brief review was conducted to identify transmission competent arthropod vectors, vertebrate hosts, and vector-host interactions for JEV. NC and other areas may be at risk for JEV emergence because of factors such as active international trade, volume of swine production, permissive climate, and widespread occurrence of potential vector species. Improved knowledge of the spatial distribution of swine farms, tracking movement of live swine, assessment of vector competence/capacity and blood feeding habits of potential JEV vectors, investigation of a JEV sentinel surveillance system, and assessment of efficacy for current biosecurity and control measures is needed to protect public and veterinary health.

MP44-07 RELATIONSHIP BETWEEN RENAL PELVIS PRESSURE AND POST-URETEROSCOPY INFECTION IN A LIVE SWINE MODEL

You have accessJournal of UrologyCME1 May 2022MP44-07 RELATIONSHIP BETWEEN RENAL PELVIS PRESSURE AND POST-URETEROSCOPY INFECTION IN A LIVE SWINE MODEL David Hinojosa-Gonzalez, Christina Kottooran, Jennifer Saunders, Marle Franco, and Brian Eisner David Hinojosa-GonzalezDavid Hinojosa-Gonzalez More articles by this author , Christina KottooranChristina Kottooran More articles by this author , Jennifer SaundersJennifer Saunders More articles by this author , Marle FrancoMarle Franco More articles by this author , and Brian EisnerBrian Eisner More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002610.07AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Urosepsis is reported to occur after 5% of ureteroscopic stone procedures; rates of pyelonephritis are higher. In this study, a live swine model was used to evaluate the relationship between renal pelvis pressure and infection after ureteroscopy. METHODS: In anesthetized pigs (n=13; female; ∼60 kg each), ureteroscopy was performed as follows: cystoscopy was performed to position a 0.014” pressure sensor guidewire (Comet™, Boston Scientific, Marlborough, MA) in the renal pelvis. A flexible ureteroscope was then introduced into the renal pelvis and the position of the ureteroscope and the pressure sensor wire were confirmed. Infusion of saline irrigation fluid alone or with a standardized concentration of uropathogenic e. coli strain CFT073 (1.5 x 107 CFU/ml) at target renal pelvic pressures (37 mm Hg and 75 mm Hg) was maintained for 60 minutes using a pressure bag and instantaneous feedback from the pressure-sensing guidewire. Venous blood sampling was performed during the procedure as well as at 1, 3,6, 12, and 24 hours after surgery. Vital signs were monitored, inflammatory biomarkers were assayed, and renal tissue and blood cultures were obtained. RESULTS: Thirteen (13) pig kidneys were used during the study and study groups were as follows: 37 mm Hg with saline irrigation (n=3), 75 mm Hg with saline irrigation (n=3), 37 mm Hg with saline irrigation with 1.5 x 107 CFU/ml e. coli added (n=3), and 75 mm Hg with saline irrigation with 1.5 x 107 CFU/ml e. coli added (n=4). Table 1 shows the results of the study: changes in inflammatory biomarkers were most pronounced in the 75 mm Hg saline irrigation + e. coli. All kidneys in both groups treated with saline + e. coli irrigation cultured positive for bacteria but interestingly, bacteremia was seen in 0/4 animals treated at 37 mm Hg with saline + e. coli irrigation and 4/4 animals treated at 75 mm Hg with saline + e. coli irrigation. CONCLUSIONS: In this study of a swine model of ureteroscopy, irrigation with saline + e. coli produced an inflammatory response as well as positive kidney cultures (i.e. pyelonephritis). However, bacteremia was only seen in animals treated at 75 mmHg. These data suggest that there may be a renal pelvis pressure threshold above which it is more likely that animals with infected urine may develop post-ureteroscopy bacteremia. Source of Funding: Boston Scientific Corporation © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e754 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information David Hinojosa-Gonzalez More articles by this author Christina Kottooran More articles by this author Jennifer Saunders More articles by this author Marle Franco More articles by this author Brian Eisner More articles by this author Expand All Advertisement PDF DownloadLoading ...

Has the Spread of African Swine Fever in the European Union Been Impacted by COVID-19 Pandemic?

African Swine Fever (ASF) is a contagious viral disease of domestic and wild pigs, listed as notifiable by the World Organization for Animal Health (OIE). It causes substantial economic losses to pig farming in the affected countries, with consequent enormous damage to livestock production due to mortality of the animals, and to the restrictions on national and international trade in pigs and derivative products that the presence of the infection implies. To prevent or reduce the risk of ASF introduction, the World Trade Organization (WTO) and the OIE recommend preventive and control measures, such as the ban of live swine and their products traded from ASF-affected to ASF-free countries or zones. The current spread of ASF into Europe poses a serious risk to the industrialized and small-scale pig sector, as demonstrated by observed cases in different EU areas. In this paper the authors discuss the impact of the COVID-19 pandemic on ASF, and the indirect effects including the impact on animal health and disease management. They suggest that the COVID-19 pandemic has severely affected animal disease surveillance control. ASF requires rapid responses and continuous monitoring to identify outbreaks and prevent their spread, and both aspects may have been greatly reduced during the COVID-19 pandemic.