White Swine Research Articles

Role of Sex and Early Life Stress Experience on Porcine Cardiac and Brain Tissue Expression of the Oxytocin and H2S Systems

Early life stress (ELS) significantly increases the risk of chronic cardiovascular diseases and may cause neuroinflammation. This post hoc study, based on the material available from a previous study showing elevated “serum brain injury markers” in male control animals, examines the effect of sex and/or ELS on the cerebral and cardiac expression of the H2S and oxytocin systems. Following approval by the Regional Council of Tübingen, a randomized controlled study was conducted on 12 sexually mature, uncastrated German Large White swine of both sexes. The control animals were separated from their mothers at 28–35 days, while the ELS group was separated at day 21. At 20–24 weeks, animals underwent anesthesia, ventilation, and surgical instrumentation. An immunohistochemical analysis of oxytocin, its receptor, and the H2S-producing enzymes cystathionine-β-synthase and cystathionine-γ-lyase was performed on hypothalamic, prefrontal cortex, and myocardial tissue samples. Data are expressed as the % of positive tissue staining, and differences between groups were tested using a two-way ANOVA. The results showed no significant differences in the oxytocin and H2S systems between groups; however, sex influenced the oxytocin system, and ELS affected the oxytocin and H2S systems in a sex-specific manner. No immunohistochemical correlate to the elevated “serum brain injury markers” in male controls was identified.

Cardiosphere derived cell secretome therapy after experimental myocardial infarction: effects of intracoronary administration on ventricular tachycardia inducibility and cardiac function

Abstract Background Myocardial infarction (MI) carries high risk of sudden cardiac death due to the development of ventricular tachycardia (VT) which is caused by viable myocytes located within the infarct scar tissue [1]. Cardiosphere derived cell secretome (S-CDCs) has been demonstrated to possess antiarrhythmic properties when delivered transendocardially [2]. Further, S-CDCs has been proven to reduce scar size and increase viable myocardial mass in chronic MI [3]. Purpose The objective of this study was to evaluate the effects of an intracoronary (IC) administration of S-CDCs on VT inducibility and cardiac function in a porcine MI model. Methods After obtaining the approval of the Institutional Animal Care and Use Committee, 14 Large White swine were subjected to closed chest MI induction carrying out balloon occlusion of the left anterior descending coronary artery (below the second diagonal branch) for 150 minutes. One month after MI creation, pigs received an IC administration of saline (CON; 5mL; n=7) or S-CDCs (S-CDCs; 9.16 mg of protein in 5mL of saline; n=7). VT inducibility and magnetic resonance (MR) studies were performed pre- and four months post-injection determining ejection fraction (EF), infarct size (IS) and indexed end diastolic and systolic volumes (EDVi, ESVi). Results Before injection VT was inducible in all cases and no differences were observed between groups in any MR-derived parameter (figure). IC infusion was successful in all swine. At four months VT inducibility study revealed lower inducibility rates in S-CDCs compared to CON (57% versus 100%; p=0.05). At this timepoint EF was higher in S-CDCs (35±10% versus 29±10%) although differences between groups were not statistically significant. Conversely, IS was significantly lower in S-CDCs (12±3% versus 16±2% (p=0.03)). Moreover, a trend towards lower ventricular volumes (EDVi: 83±18mL/m² versus 88±29mL/m² and ESVi: 56±20mL/m² versus 64±27mL/m²) was detected in this group. Conclusions The IC administration of S-CDCs suggests a potential reduction on post-MI VT development as well as a beneficial effect on cardiac function. This therapy seems to reduce IS in this porcine MI model.MR derived parameters

Feasibility and safety of Stanford A aortic dissection complete endovascular repair system in a porcine model

BackgroundAcute type A aortic dissection (ATAAD) is a catastrophic disease with high morbidity and mortality. Although open surgery is still the gold standard for the treatment of ATAAD, some patients, with advanced age and multiple comorbidities, can only receive medical management alone. Nowadays, thoracic aortic endovascular repair (TEVAR) provides a potential treatment option for the patient with ATAAD, but traditional stent grafts (SGs), which are not designed for the ATAAD, are inapplicable to the unique anatomy of the aortic arch. Therefore, we innovatively created the BRIDGE system (Chuangxin Medical, Shenzhen, China), a complete endovascular reconstruction system designed to treat ATAAD. This study aimed to evaluate the feasibility and safety of the novel Stanford A aortic dissection complete endovascular reconstruction system in a porcine model.MethodThe BRIDGE system consists of the type A stent system and the type C stent system. Between November 2020 and March 2021, three white swine were utilized in the study. The BRIDGE system was deployed via the transcatheter approach under angiographic guidance. The swine(n = 3) treated with our system were evaluated using angiography before sacrifice 1-month after implantation, which was followed by gross specimen evaluation and histological examination of harvested tissues.ResultThe acute procedure success rate was 100% (3/3). The immediate post-procedural angiography showed that both type A SGs and type C SGs were deployed in satisfactory locations, with patency of the supra-aortic trunk and no endoleak. The cumulative mortality of 30-day was 0% without any adverse events. No device migration or leakage was observed angiographically, before sacrifice. The gross observation confirmed a type A SG covered part of the entry of anonyma. Favorable endothelialization, no thrombogenesis, and slight inflammatory infiltration of the tissues around the device were confirmed by microscopic examinations in all pigs.ConclusionIt was feasible and secure to use Stanford A aortic dissection complete endovascular reconstruction system to implement a transcatheter endovascular repair in a porcine model. With this novel system, treating acute type A aortic dissection may be more efficient and secure in human.

Seasonal distribution of Calliphoridae and Mesenbrinellidae (Diptera) associated with the decomposition of a clothed animal model in a forest reserve in the Central Amazon.

We evaluated the effects of seasonality on the richness and abundance of dipterans of the families Calliphoridae and Mesembrinellidae associated with the decomposition of a clothed Large White swine Sus scrofa domesticus(Artiodactyla: Suidae) carcass. Experiments were carried out in less rainy, rainy, and intermediate periods between 2010 and 2011 at Reserva Florestal Ducke, Manaus, Amazonas. Two pig carcasses, each weighing approximately 40 kg, were used in each period. A total of 63,872 individuals of 18 species of Calliphoridae and Mesembrinellidae were collected. The abundance and richness of these dipteran families were influenced by the interaction between period and decomposition stage. The compositions of the Calliphoridae and Mesembrinellidae assemblages differed among periods, with the fauna of the less rainy period being less similar to those of the intermediate and rainy periods than they were to each other. Three species were selected as indicators for the less rainy period, namely Paralucilia pseudolyrcea (Mello, 1969) (Diptera, Calliphoridae), Paralucilia nigrofacialis (Mello, 1969) (Diptera, Calliphoridae), and Eumesembrinella randa (Walker, 1849) (Diptera,Mesembrinellidae) while Chloroprocta idioidea (Robineau-Desvoidy, 1830) (Dipetra, Calliphoridae) was selected as an indicator species for the rainy period; no taxon was selected as an indicator of the intermediate period. Among decomposition stages, only fermentation and black putrefaction had indicator taxa, with Hemilucilia souzalopesi Mello, 1972 (Diptera, Calliphoridae and Chysomya putoria(Wiedemann, 1830) (Diptera, Calliphoridae), respectively. Clothes did not prevent the laying of eggs and became a kind of protection for immature stages. The clothed model presented a delay in decomposition compared to other studies developed in the Amazon region.

Porcine blood cell and brain tissue energy metabolism: Effects of "early life stress".

Background: Early Life Stress (ELS) may exert long-lasting biological effects, e.g., on PBMC energy metabolism and mitochondrial respiration. Data on its effect on brain tissue mitochondrial respiration is scarce, and it is unclear whether blood cell mitochondrial activity mirrors that of brain tissue. This study investigated blood immune cell and brain tissue mitochondrial respiratory activity in a porcine ELS model. Methods: This prospective randomized, controlled, animal investigation comprised 12 German Large White swine of either sex, which were weaned at PND (postnatal day) 28-35 (control) or PND21 (ELS). At 20-24weeks, animals were anesthetized, mechanically ventilated and surgically instrumented. We determined serum hormone, cytokine, and "brain injury marker" levels, superoxide anion (O2 •¯) formation and mitochondrial respiration in isolated immune cells and immediate post mortem frontal cortex brain tissue. Results: ELS animals presented with higher glucose levels, lower mean arterial pressure. Most determined serum factors did not differ. In male controls, TNFα and IL-10 levels were both higher than in female controls as well as, no matter the gender in ELS animals. MAP-2, GFAP, and NSE were also higher in male controls than in the other three groups. Neither PBMC routine respiration and brain tissue oxidative phosphorylation nor maximal electron transfer capacity in the uncoupled state (ETC) showed any difference between ELS and controls. There was no significant relation between brain tissue and PBMC, ETC, or brain tissue, ETC, and PBMC bioenergetic health index. Whole blood O2 •¯ concentrations and PBMC O2 •¯ production were comparable between groups. However, granulocyte O2 •¯ production after stimulation with E. coli was lower in the ELS group, and this effect was sex-specific: increased O2 •¯ production increased upon stimulation in all control animals, which was abolished in the female ELS swine. Conclusion: This study provides evidence that ELS i) may, gender-specifically, affect the immune response to general anesthesia as well as O2 •¯ radical production at sexual maturity, ii) has limited effects on brain and peripheral blood immune cell mitochondrial respiratory activity, and iii) mitochondrial respiratory activity of peripheral blood immune cells and brain tissue do not correlate.

Alda-1 alleviates brain injury after cardiopulmonary resuscitation by regulating acyl-CoA synthetase long-chain family member 4/glutathione peroxidase 4 pathway-mediated ferroptosis in swine

To investigate whether the acetaldehyde dehydrogenase 2 specific activator, Alda-1, can alleviate brain injury after cardiopulmonary resuscitation (CPR) by inhibiting cell ferroptosis mediated by acyl-CoA synthetase long-chain family member 4/glutathione peroxidase 4 (ACSL4/GPx4) pathway in swine. Twenty-two conventional healthy male white swine were divided into Sham group (n = 6), CPR model group (n = 8), and Alda-1 intervention group (CPR+Alda-1 group, n = 8) using a random number table. The swine model of CPR was reproduced by 8 minutes of cardiac arrest induced by ventricular fibrillation through electrical stimulation in the right ventricle followed by 8 minutes of CPR. The Sham group only experienced general preparation. A dose of 0.88 mg/kg of Alda-1 was intravenously injected at 5 minutes after resuscitation in the CPR+Alda-1 group. The same volume of saline was infused in the Sham and CPR model groups. Blood samples were collected from the femoral vein before modeling and 1, 2, 4, 24 hours after resuscitation, and the serum levels of neuron specific enolase (NSE) and S100 β protein were determined by enzyme-linked immunosorbent assay (ELISA). At 24 hours after resuscitation, the status of neurologic function was evaluated by neurological deficit score (NDS). Thereafter, the animals were sacrificed, and brain cortex was harvested to measure iron deposition by Prussian blue staining, malondialdehyde (MDA) and glutathione (GSH) contents by colorimetry, and ACSL4 and GPx4 protein expressions by Western blotting. Compared with the Sham group, the serum levels of NSE and S100β after resuscitation were gradually increased over time, and the NDS score was significantly increased, brain cortical iron deposition and MDA content were significantly increased, GSH content and GPx4 protein expression in brain cortical were significantly decreased, and ACSL4 protein expression was significantly increased at 24 hours after resuscitation in the CPR model and CPR+Alda-1 groups, which indicated that cell ferroptosis occurred in the brain cortex, and the ACSL4/GPx4 pathway participated in this process of cell ferroptosis. Compared with the CPR model group, the serum levels of NSE and S100 β starting 2 hours after resuscitation were significantly decreased in the CPR+Alda-1 group [NSE (μg/L): 24.1±2.4 vs. 28.2±2.1, S100 β (ng/L): 2 279±169 vs. 2 620±241, both P < 0.05]; at 24 hours after resuscitation, the NDS score and brain cortical iron deposition and MDA content were significantly decreased [NDS score: 120±44 vs. 207±68, iron deposition: (2.61±0.36)% vs. (6.31±1.66)%, MDA (μmol/g): 2.93±0.30 vs. 3.68±0.29, all P < 0.05], brain cortical GSH content and GPx4 expression in brain cortical was significantly increased [GSH (mg/g): 4.59±0.63 vs. 3.51±0.56, GPx4 protein (GPx4/GAPDH): 0.54±0.14 vs. 0.21±0.08, both P < 0.05], and ACSL4 protein expression was significantly decreased (ACSL4/GAPDH: 0.46±0.08 vs. 0.85±0.13, P < 0.05), which indicated that Alda-1 might alleviate brain cortical cell ferroptosis through regulating ACSL4/GPx4 pathway. Alda-1 can reduce brain injury after CPR in swine, which may be related to the inhibition of ACSL4/GPx4 pathway mediated ferroptosis.

Protective role and mechanism of tubastatin A on renal and intestinal injuries after cardiopulmonary resuscitation in swine

To investigate the protective effect and potential mechanism of tubastatin A (TubA), a specific inhibitor of histone deacetylase 6 (HDAC6), on renal and intestinal injuries after cardiopulmonary resuscitation (CPR) in swine. Twenty-five healthy male white swine were divided into Sham group (n = 6), CPR model group (n = 10) and TubA intervention group (n = 9) using a random number table. The porcine model of CPR was reproduced by 9-minute cardiac arrest induced by electrical stimulation via right ventricle followed by 6-minute CPR. The animals in the Sham group only underwent the regular operation including endotracheal intubation, catheterization, and anesthetic monitoring. At 5 minutes after successful resuscitation, a dose of 4.5 mg/kg of TubA was infused via the femoral vein within 1 hour in the TubA intervention group. The same volume of normal saline was infused in the Sham and CPR model groups. Venous samples were collected before modeling and 1, 2, 4, 24 hours after resuscitation, and the levels of serum creatinine (SCr), blood urea nitrogen (BUN), intestinal fatty acid binding protein (I-FABP) and diamine oxidase (DAO) in serum were determined by enzyme-linked immunoadsordent assay (ELISA). At 24 hours after resuscitation, the upper pole of left kidney and terminal ileum were harvested to detect cell apoptosis by TdT-mediated dUTP-biotin nick end labeling (TUNEL), and the expression levels of receptor-interacting protein 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL) were detected by Western blotting. After resuscitation, renal dysfunction and intestinal mucous injury were observed in the CPR model and TubA intervention groups when compared with the Sham group, which was indicated by significantly increased levels of SCr, BUN, I-FABP and DAO in serum. However, the serum levels of SCr and DAO starting 1 hour after resuscitation, the serum levels of BUN starting 2 hours after resuscitation, and the serum levels of I-FABP starting 4 hours after resuscitation were significantly decreased in the TubA intervention group when compared with the CPR model group [1-hour SCr (μmol/L): 87±6 vs. 122±7, 1-hour DAO (kU/L): 8.1±1.2 vs. 10.3±0.8, 2-hour BUN (mmol/L): 12.3±1.2 vs. 14.7±1.3, 4-hour I-FABP (ng/L): 661±39 vs. 751±38, all P < 0.05]. The detection of tissue samples indicated that cell apoptosis and necroptosis in the kidney and intestine at 24 hours after resuscitation were significantly greater in the CPR model and TubA intervention groups when compared with the Sham group, which were indicated by significantly increased apoptotic index and markedly elevated expression levels of RIP3 and MLKL. Nevertheless, compared with the CPR model group, renal and intestinal apoptotic indexes at 24 hours after resuscitation in the TubA intervention group were significantly decreased [renal apoptosis index: (21.4±4.6)% vs. (55.2±9.5)%, intestinal apoptosis index: (21.3±4.5)% vs. (50.9±7.0)%, both P < 0.05], and the expression levels of RIP3 and MLKL were significantly reduced [renal tissue: RIP3 protein (RIP3/GAPDH) was 1.11±0.07 vs. 1.39±0.17, MLKL protein (MLKL/GAPDH) was 1.20±0.14 vs. 1.51±0.26; intestinal tissue: RIP3 protein (RIP3/GAPDH) was 1.24±0.18 vs. 1.69±0.28, MLKL protein (MLKL/GAPDH) was 1.38±0.15 vs. 1.80±0.26, all P < 0.05]. TubA has the protective effect on alleviating post-resuscitation renal dysfunction and intestinal mucous injury, and its mechanism may be related to inhibition of cell apoptosis and necroptosis.

Baseline Values and Kinetics of IL-6, Procalcitonin, and TNF-α in Landrace-Large White Swine Anesthetized with Propofol-Based Total Intravenous Anesthesia.

The baseline levels of various inflammatory mediators and their changes during anesthesia in swine are not known. The aim of this animal study was to measure the baseline values and kinetics of interleukin-6, procalcitonin, and tumor necrosis factor-alpha in healthy Landrace-Large White swine anesthetized with propofol-based total intravenous anesthesia. We included 8 healthy male pigs with an average weight of 19 ± 2 kg (aged 10-15 weeks) that were subjected to propofol-based total intravenous anesthesia for 8 hours. Complete blood count, serum chemistry, and serum levels of interleukin-6, procalcitonin, and tumor necrosis factor-alpha were analyzed, and serum levels were quantified hourly. Blood was also collected for bacterial culturing. Baseline values of interleukin-6 and procalcitonin were 18 pg/ml and 21 ng/ml, respectively, while tumor necrosis factor-alpha was not detectable during collection of baseline samples. A statistically significant difference was observed in interleukin-6 levels between time points (p < 0.0001). Procalcitonin increased with time, but there were no significant differences between time points (p = 0.152). Tumor necrosis factor-alpha increased until the 3rd hour of propofol-based total intravenous anesthesia, while after the 4th hour, it gradually decreased, reaching its baseline undetectable values by the 7th hour (p < 0.001). Our results can serve as the basis for further translational research.

A Novel Fenestrating Device: Quick Fenestrater for Reconstructing Supra-aortic Arteries In Situ During Thoracic Endovascular Aortic Repair

BackgroundIn situ fenestration (ISF) is an effective approach for reconstructing supra-aortic branches during thoracic endovascular aortic repair (TEVAR). A dedicated device is needed for ISF. MethodsThe Quick Fenestrater (QF) underwent in vitro, animal-based, and initial clinical testing. In vitro, the polytetrafluoroethylene and Dacron aortic endografts were fenestrated using the QF, and the structure of the graft, fenestration hole, and shed particulate material were evaluated. Eight white swine had QF-aided ISF combined with TEVAR and bridge-stent implantation. The outcomes were assessed using intraoperative angiography and biopsy. Finally, 13 patients were treated with QF-assisted ISF combined with TEVAR, and the success rate, technical details, and intra- and postoperative complications were recorded. ResultsThe endograft structure was not damaged during in vitro testing. The fenestration hole was clean, and no particulate material was detected. In animal studies, all animals survived, the supra-aortic arteries were patent, and the endografts and bridge stents had normal morphology. In clinical studies, the technical success rate was 100%, and no fenestration-related neurologic complications or death occurred. One patient had a local access-related hematoma perioperatively and recovered after conservative treatment. Three patients had type III endoleaks, which resolved with no additional treatment. During a mean follow-up of 22.1 ± 6 months, no thoracic complications were identified, and the bridge stents were patent with no endoleaks. No adverse cerebrovascular events, cardiovascular events, or death occurred. ConclusionsQF-assisted ISF is a safe and effective method for the reconstruction of supra-aortic branches during TEVAR. Intermediate-term follow-up results validate the application of the novel fenestration device.

Activation of Skeletal Muscle Satellite Cells by a Device Simultaneously Applying High-Intensity Focused Electromagnetic Technology and Novel RF Technology: Fluorescent Microscopy Facilitated Detection of NCAM/CD56.

BackgroundMyosatellite cells are myogenic stem cells that can transform to provide nuclei for existing muscles or generate new muscle fibers as documented after extended exercise programs.ObjectivesThe authors investigated whether the simultaneous application of High-Intensity Focused Electromagnetic (HIFEM) and Synchrode radiofrequency (RF) affects the levels of satellite cells similarly as the prolonged exercise does to achieve muscle growth.MethodsThree 30-minute simultaneous HIFEM and Synchrode RF treatments (once a week) were administered over the abdominal area of 5 Large White swine aged approximately 6 months. All animals were anesthetized during the treatments and biopsy acquisition. Biopsies of muscle tissue were collected at baseline, 4 days, 2 weeks, and 1 month post-treatment. After binding the specific antibodies, the NCAM/CD56 levels, a marker of activated satellite cells, were quantified employing the immunofluorescence microscopy technique with a UV lamp.ResultsExamined slices showed a continuous increase in satellite cell levels throughout the study. Four days after the treatment, we observed a 26.1% increase in satellite cells, which increased to 30.2% at 2-week follow-up. Additional histological analysis revealed an increase in the cross-sectional area of muscle fibers and the signs of newly formed fibers of small diameters at 2 weeks after the treatment. No damage to muscle tissue and no adverse effects related to the treatment were observed.ConclusionsThe findings indicate that the simultaneous application of HIFEM and novel Synchrode RF treatment can initiate differentiation of satellite cells to support the growth of existing muscles and, presumably, even the formation of new myofibers.

Effects of hypothermia on Ca2+ /calmodulin-dependent protein kinase II and cell autophagy in brain tissues after cardiac arrest and cardiopulmonary resuscitation in swine

Objective To evaluate the effects of hypothermia on Ca2+ /calmodulin-dependent protein kinase Ⅱ (CaMKⅡ) and cell autophagy in brain tissues after cardiac arrest and cardiopulmonary resuscitation (CA-CPR) in swine. Methods Twenty-one healthy male white swine, weighing 33-40 kg, were divided into 3 groups using a random number table method: sham operation group (group S, n=5), CA-CPR group (n=8) and hypothermia group (group H, n=8). The experimental model of CA-CPR was established in CA-CPR and H groups.The Swan-Ganz catheters were placed in the right femoral artery and vein to monitor the pressure of thoracic aorta and right atrium and body temperature and to collect blood samples.A pacing catheter was advanced from the right external jugular vein into the right ventricle.Ventricular fibrillation was induced by using a 1 mA alternating current through the pacing catheter.Once ventricular fibrillation was successfully induced, mechanical ventilation was discontinued for 8 min, and then CPR was initiated.Epinephrine 20 μg/kg was intravenously injected at 2.5 min of CPR, followed by repetition once every 3 min.Defibrillation was delivered at 5 min of CPR, and then spontaneous circulation was evaluated.If the spontaneous circulation was not restored, CPR was immediately resumed for 2 min, and then defibrillation was delivered again.Mechanical ventilation was continued for 30 h after successful CPR.At 5 min after successful resuscitation, body temperature was decreased to 33 ℃ by using a cooling blanket, then maintained at 33 ℃ until 24 h after resuscitation, and finally increased at a rate of 1 ℃/h for 5 h in group H. The temperature was maintained at a normal level of 37.5-38.5 ℃ with the aid of a cooling blanket in S and CA-CPR groups.At 1, 6, 12, 24 and 30 h after resuscitation (T1-5), blood samples were collected from the femoral vein for measurement of the concentration of neuron specific enolase (NSE) and S100β protein in serum by enzyme-linked immunosorbent assay.Five animals in each group were then sacrificed, and brains were removed to determine the expression of CaMKⅡ, microtubule-associated protein 1 light chain 3 Ⅱ (LC3Ⅱ) and p62 in cerebral cortex by Western blot.Neurological deficit score was evaluated in the remaining three swine at 48, 72 and 96 h after resuscitation (T6-8) in CA-CPR and H groups. Results Compared with group S, the concentrations of NSE and S100β protein in serum were significantly increased at T1-5, the expression of CaMKⅡ and LC3Ⅱ in cerebral cortex was up-regulated, and the expression of p62 in cerebral cortex was down-regulated in CA-CPR and H groups (P<0.05). Compared with group CA-CPR, the concentrations of NSE and S100β protein in serum were significantly decreased at T3-5, the neurological deficit score was decreased at T6-8, the expression of CaMKⅡ and LC3Ⅱ in cerebral cortex was down-regulated, and the expression of p62 in cerebral cortex was up-regulated in group H (P<0.05). Conclusion The mechanism by which hypothermia alleviates brain injury after CA-CPR may be related to inhibiting CaMKⅡ activation and reducing cell autophagy in brain tissues of swine. Key words: Hypothermia, induced; Heart arrest; Cardiopulmonary resuscitation; Reperfusion injury; Brain; Ca2+ /calmodulin-dependent protein kinase Ⅱ; Autophagy

The effect of a feed additive supplemented with porcine plasma protein on growth performance and selected biochemical indices of nursing piglets

The aim of this study was to evaluate the health state, performance, and selected serum biochemical indices in nursing piglets after supplementation of a feed additive containing porcine plasma protein in comparison to the control group fed a standard pre-starter feed mixture. The study was carried out in the conditions of industrial farming. Four sows of the Large White swine breed with their litters were included in the study. Piglets were homogenously distributed into control (22) and experimental (24) groups according to weight and sex. Piglets in both groups suckled their mothers' milk. In addition, piglets in the experimental group were also fed a feed supplemented by porcine plasma protein (5%), starting on the third daypost partum, whereas piglets in the control group were offered a standard pre-starter feed mixture. We recorded average daily weight gains calculated per the 27-day trial, and body weight at weaning. Clinical findings, mortality, and selected biochemical indices of protein (total immunoglobulins, total protein, albumin, creatinine, urea), and energy (glucose, total cholesterol, total lipids) metabolism were assessed as well. Results of the study showed a significant difference (P&lt; 0.01) in average daily weight gains in the experimental group compared to the control group (0.245 kg and 0.177 kg, respectively). Addition of plasma protein in the experimental group also resulted in a significantly higher serum concentration of total immunoglobulins, total protein and creatinine, and a significantly lower concentration of urea and albumin in this group compared to the control group at weaning.

Randomized Trial of Spheroid Reservoir Bioartificial Liver in Porcine Model of Posthepatectomy Liver Failure.

Acute liver failure (ALF) is a catastrophic condition that can occur after major liver resection. The aim of this study was to determine theeffects ofthe spheroid reservoir bio-artificial liver (SRBAL) on survival, serum chemistry, and liver regeneration in posthepatectomy ALF pigs. Wild-type large white swine (20 kg-30 kg) underwentintracranial pressure (ICP) probe placementfollowed by 85% hepatectomy. Computed tomography (CT) volumetrics were performed to measure the extent of resection, and at 48 hours following hepatectomy to assess regeneration of the remnant liver. Animals were randomized into three groups based on treatment delivered 24-48 hours after hepatectomy: Group1-standard medical therapy (SMT, n = 6); Group2-SMT plus bio-artificial liver treatment using no hepatocytes (0 g, n = 6); and Group3-SMT plus SRBAL treatment using 200 g of primary porcine hepatocyte spheroids (200 g, n = 6). The primary endpoint was survival to 90 hours following hepatectomy. Death equivalent was defined as unresponsive grade 4 hepatic encephalopathy or ICP greater than 20 mmHg with clinical evidence of brain herniation. All animals in both (SMT and 0 g) control groups met the death equivalent before 51 hours following hepatectomy. Five of 6 animals in the 200-g group survived to 90 hours (P < 0.01). The mean ammonia, ICP, and international normalized ratio values were significantly lower in the 200-g group. CT volumetrics demonstrated increased volume regeneration at 48 hours following hepatectomy in the 200-g group compared with the SMT (P < 0.01) and 0-g (P < 0.01) groups. Ki-67 staining showed increased positive staining at 48 hours following hepatectomy (P < 0.01). Conclusion: The SRBAL improved survival, reduced ammonia, and accelerated liver regeneration in posthepatectomy ALF. Improved survival was associated with a neuroprotective benefit of SRBAL therapy. These favorable results warrant further clinical testing of the SRBAL.

The Influence of Herbal Supplement on the Productivity and Health Condition of Fattening Pigs

A scientific and economic experiment with 26 swine of the breed combination ♀Dunabe White Swine x (Еnglish Landrace x Pietrain) x ♂Danish Landrace was carried out in Agricultural Institute – Shumen. The animals were divided into two groups of 13, raised in separate boxes. The experiment was divided into two sub-periods, starting at an average live weight of 30.63 kg and ending at 110 kg live weight. During the first sub-period (30 to 60 kg live weight), the swine from first group were given a combined feed containing 16.4% crude protein, 0.80% lysine, 0.87% calcium and 0.66% phosphorus, and during the second period (from 60 to 110 kg live weight) – 15.5% crude protein, 0.85% lysine, 0.64% calcium and 0.45% phosphorus. Animals from the second group were given the same combined feed, accordingly for the first and second sub-periods, with the addition of herbal supplement (30% nettle leaves, 5% dandelion, 5% hawthorn, 10% goosegrass, and 50% rosehip flour) at 10g per day. The usage of herbal supplement in the compound feed for fattening pigs from the Dunabe White breed, from 30 to 110 kg live weight, does not significantly affect the growth rate and feed conversion ratio per kg gain. The animals from the experimental (II) group have a higher average daily increase during the period from 60 to 110 kg live weight with 4.34% in comparison to those from group I, but all differences are statistically insignificant. There is a tendency for slightly better fat characteristics in animals receiving the herbal supplement. The usage of the tested herbal supplement needs additional studies to detect the effects on fattening pigs.

Neuromuscular blockade of atracurium in permissive hypercapnic versus normocapnic swine undergoing laparoscopy.

Neuromuscular blocking agents (NMBAs) are commonly used in experimental laparoscopy in swine undergoing carbon dioxide pneumoperitoneum. Hypercapnia may be present and may prolong NMBAs’ pharmacologic activity. The aim of this study is to evaluate the effect of permissive hypercapnia on the neuromuscular blockade of atracurium in swine. Six Large White swine weighing 30.5 ± 1.6 kg were sedated with intramuscular ketamine and medetomidine, after which anaesthesia was induced with propofol and maintained with sevoflurane. Atracurium 0.4 mg/kg was administered intravenously and the neuromuscular block monitored by acceleromyography during normocapnic and hypercapnic conditions (PaCO2 range 35–45 mmHg and 60–70 mmHg, respectively). Onset time and time to reach a train of four ratio (TOFR) of 0.7 and 0.9 were recorded. Cardiorespiratory parameters, electrolytes and acid-base status were measured under both conditions. Onset time was similar between the two conditions. Time to reach a TOFR of 0.7 and 0.9 (duration of the neuromuscular block) was longer in hypercapnic compared to normocapnic animals being 1325 ± 300 vs 855 ±111 (p = 0.002) and 1823 ± 434 vs 1218 ± 210 seconds (p = 0.005), respectively. Three hypercapnic swine had a TOF count of 2 and 1 instead of a count of 4 with fade. Permissive hypercapnia was associated with a decrease in pH from 7.444 ± 0.039 to 7.257 ± 0.025 (p < 0.001). No differences were observed for heart rate, end-tidal concentration of sevoflurane, body temperature and arterial haemoglobin saturation. Nonetheless, hypercapnic swine had a statistically significant increase in mean arterial pressure (p = 0.020) and plasma potassium concentration (p = 0.003). The values of PaCO2 achieved during hypercapnia were well tolerated in swine undergoing CO2 pneumoperitoneum for laparoscopy. Permissive hypercapnia increased the duration of the atracurium effect and caused an increase in the intensity of the neuromuscular block in few swine.

Induction of anaesthesia with remifentanil after bolus midazolam administration in Landrace/Large White swine

ObjectiveTo investigate an alternative combination for anaesthesia induction in swine. Study designRandomized, ‘blinded’ experimental study. AnimalsForty-five Landrace/Large White swine weighing 20.0±1.5 kg. MethodsPulse oximetry, heart rate (HR) and blood pressure were measured after premedication with ketamine, midazolam and atropine as well as after intubation following induction with a fixed dose of 0.2 mg kg−1 midazolam combined with 1, 2, 3, 4 or 5 μg kg−1 remifentanil (groups R1, R2, R3, R4 and R5, respectively). Intubation was evaluated using a numerical scoring system assessing jaw relaxation, resistance to the laryngoscope, vocal cord position, vocal cord movement and response to intubation. The time required to intubate and necessity for an additional midazolam dose were recorded. Baseline and post-intubation variables were compared with paired t tests, whereas for differences between the remifentanil groups the Spearman's rank correlation coefficient was estimated. Multivariate regression analysis was performed to disentangle the effect of remifentanil dose and the additional midazolam. ResultsHigher dose of remifentanil was associated with better vocal cord position (p<0.001), better response to intubation (p<0.001), shorter time required for intubation (p=0.030) and less frequent necessity for additional administration of midazolam (p=0.004). In total, 39.5% of the animals required additional midazolam. In groups R1, R4 and R5, there were decreases in HRs (p=0.009, p=0.008 and p=0.032, respectively) between baseline and post-intubation phase; in groups R3 and R4, there were decreases in systolic blood pressure (p=0.040 and p=0.019, respectively). In the multivariate analysis, remifentanil dose was not associated with the observed changes in haemodynamic variables. One animal developed apnoea and four electrocardiographic anomalies; all resolved without pharmaceutical interventions. Conclusions and clinical relevanceA combination of 0.2 mg kg−1 midazolam with 4 or 5 μg kg−1 remifentanil may provide an alternative method of anaesthesia induction for swine.

Transesophageal Echocardiography in Swine: Establishment of a Baseline

The porcine model is a commonly used animal model in cardiovascular research. Along with new innovative operative techniques, choice of the optimal imaging technique is crucial. Transesophageal echocardiography (TEE) is a reliable imaging tool is highly important in a large number of experimental evaluations. But so far, TEE data for swine are limited, and few standard values have been established for the porcine model. The experience and baseline results for TEE in 45 swine are presented in this study. A full TEE examination was conducted in 45 German landrace or German large white swine, with an average body weight of 49 ± 3 kg, before experimental off-pump mitral valved stent implantation. Additionally hemodynamic measurements were evaluated. The valve implantation procedure was guided solely by real-time 3-D TEE. Baseline values of standard echocardiographic parameters are provided and, where appropriate, compared with human reference values. TEE proved to be an adequate imaging technique in this experimental porcine animal model. The baseline TEE and hemodynamic parameters established for the widely used porcine model can serve as a reference in future studies.

Splenectomy Versus Sham Splenectomy in a Swine Model of Controlled Hemorrhagic Shock.

Splenectomy is controversial in acute hemorrhagic shock models. To compare splenectomized (SP) versus sham-splenectomized (SSP) swine during acute controlled hemorrhage. Twenty-six male Landrace White swine (mean body weight ± standard deviation, 33.8 ± 2.9 kg) were used. Ethics approval was obtained. Landrace swine underwent splenectomy (n = 13) or sham-splenectomy (n = 13), were bled to mean arterial blood pressure (MAP) of 40 mm Hg, which was held for 60 min, given 125 mL IV RescueFlow, held for a further 60 min, given whole blood, and held for a final 60 min. Tissue oxygen saturation, thromboelastography, oncotic pressure, urine volume and specific gravity, complete blood count, serum chemistry, body temperature, hematocrit, total solids, arterial and mixed venous blood gas, bispectral index, SAP, MAP, DAP, cardiac index, total blood volume (TBV) removed and returned, rate of hemorrhage and transfusion, spleen weight, heart rate (HR), arterial pH, lactate, PaO2, PaCO2, respiratory rate, cranial mesenteric and renal artery blood flow were recorded. Groups were compared using two-way ANOVA with post hoc Bonferroni (P < 0.05) for repeated measures or t test for non-repeated measures. Compared with the SSP swine, SP swine had higher HR post-splenectomy for the duration of the experiment (P < 0.03), and higher hematocrits at 15 and 60 min post splenectomy (P < 0.01, P < 0.001, respectively). SSP swine had greater TBV removed during hemorrhage (P < 0.01); however, when blood loss based on splenic weight was considered, TBV removed was similar between groups. Splenectomy likely accounts for the transient increase in hematocrit and the higher HR in SP swine prior to hemorrhage, and the differences in TBV removed between the two groups during hemorrhage. With a fixed end point model using a moderate rate of acute hemorrhage and an MAP of 40 mm Hg, splenectomy is not necessary and may confound results.

Simplified technique for 75% and 90% hepatic resection with hemodynamic monitoring in a large white swine model

BackgroundAccurate measuring of the hepatic hemodynamic parameters in humans is inconvenient. Swine has been a favorite surgical model for the study of liver conditions due to many similarities with human livers. However, pigs cannot tolerate pedicle clamping and to reduce bleeding during resection a simplified technique is required. The aim of this study is to present a simplified technique for different percentages of hepatic resection in a porcine model. MethodsTwenty-two consecutive large white pigs were operated with 75% and 90% liver resection. Computarized tomography liver volumetry is performed before and after surgery. In both types of surgery, hemodynamic monitoring was performed using a specialized apparatus. ResultsResections were performed in both groups successfully. The residual volume in the planned 75% was 235 ± 77 mL and 118 ± 119 mL in the planned 90% resection. For 75% resection, the portal flow was reduced after resection by 8.13 ± 28%, which might be part of systemic circulatory depression. However, the portal pressure increased by 20.1 ± 51%. The hepatic artery flow decreased by 63.86 ± 26.3% as well as the pressure by 5 ± 28%. The central venous pressure at the start of surgery was 3.34 ± 1.9 mm Hg and 2.8 ± 2.2 mm Hg at the end of surgery. The portacaval pressure gradient was 4.4 ± 2.9 mm Hg at the beginning of surgery and was 5.9 ± 2.8 mm Hg at the end of surgery. For 90% resection, the portal flow decreased by 33.6 ± 12.6% and the pressure increased by 104 ± 58%. The hepatic artery flow decreased by 88 ± 7%, and the pressure decreased by 5 ± 14.8%. The central venous pressure was 3.5 ± 1.7 mm Hg before resection and 3 ± 2.5 mm Hg after resection. The portacaval pressure gradient was 3.8 ± 1.1 mm Hg before resection and 8 ± 3.7 mm Hg after resection. The mean anesthesia time was 6.6 ± 1.05 h and 6.9 ± 0.5 h for 75% and 90% resection, respectively. The mean operative time was 4.6 ± 0.9 h and 5 ± 0.7 h for 75% and 90% resections, respectively. The mean time for hepatectomy was 1.23 ± 0.76 h and 2.4 ± 0.1 h for 75% and 90% resection, respectively. The mean time consumed in the measurements was 2.28 ± 1.4 h and 1.1 ± 0.3 h for 75% and 90% resections, respectively. The mean volume of aspirated fluid and blood in the 75% resection was 1062 ± 512 mL, while it was 1050 ± 354 mL in 90% resections. ConclusionsThe hereby described technique is simple and easily applicable for major liver resection in a porcine model. Portal flow decreases after 90% resection more than in 75% due to the relative reduction of remnant hepatic mass. There was a larger increase in portal pressure following 90% compared to 75% resection. The hepatic artery flow decreases more in 90% than in 75% resections.

Jailed Artery Ostia Modifications After Flow-Diverting Stent Deployment at Arterial Bifurcations: A Scanning Electron Microscopy Translational Study.

Even though flow-diverting stents are being increasingly used to treat intracranial aneurysms, the fate of jailed side branches remains controversial, with recent clinical data contradicting finding of earlier animal studies that reported patency. To quantify the surface area of the ostia after 3 months of jailing by flow-diverting stents as a more accurate means of patency evaluation. Ten large white swine were stented by flow-diverting stents placed at common carotid-ascending pharyngeal arterial bifurcation sites. A dual antiplatelet regimen was initiated 72 hours before stenting and maintained during follow-up. Optical coherence tomography was used to search for per-procedural thrombus formation. Selective control digital subtraction angiography was performed 12 weeks post-stenting. Subsequently, the stented arterial segments were harvested en bloc and observed under scanning electron microscopy, photographed, and quantified. The absence of per-procedural thrombus formation was confirmed. All ostia were patent at 12 weeks (or 3 months) post stenting, with no angiographic or scanning electron microscopy-evident thrombus formation. The mean initial ostium surface was 2 048 617 ± 731 625 μm. At 3 months, the mean nonendothelialized ostium surface was 229 218 ± 140 172 μm, and mean endothelialized ostium surface was 1 819 399 ± 672 632 μm. A statistically significant difference (reduction) was observed between the initial and 12-week ostium surfaces (P < .001), with an significant statistical power (1.000). Jailed side branches remained patent after stenting, but the surface quantifications showed significant endothelial coverage, with a significant reduction of patent ostium surfaces at 12 weeks post-stenting. APhA, ascending pharyngeal arteryCI, confidence interval3DRA, 3-dimensional rotational angiographyDSA, digital subtraction angiographyFDS, flow-diverting stentOCT, optical coherence tomographyOS, ostium surfaceSEM, scanning electron microscopy.