Landrace Pigs Research Articles

Hemofiltration Improves Blood Perfusate Conditions Leading to Improved Ex Situ Heart Perfusion.

The aim was to optimize the perfusate composition by including a hemofiltrator to the PhysioHeartplatform for ex situ heart perfusion of porcine slaughterhouse hearts. Fourteen hearts were harvested from Dutch Landrace pigs and slaughtered for human consumption. All hearts were preserved for 4 hours using static cold storage before reperfusion for 4 hours on the PhysioHeart platform. Seven hearts were assigned to the hemofiltration group, where a hemofiltrator was added to the perfusion circuit, while the control group did not receive hemofiltration. In the hemofiltration group, the perfusion fluid was filtrated for 1 hour with a flow of 1 L/hour before reperfusion. After mounting the heart, hemofiltration was maintained at 1 L/hour, and cardiac function and blood samples were analyzed at multiple time points. Preserved cardiac function was defined as a cardiac output >3.0 L/min with a mean aortic pressure >60 mm Hg and a left atrial pressure <15 mm Hg. Hemofiltration resulted in a significantly reduced potassium concentration at all time points ( p < 0.001), while sodium levels remained at baseline values ( p < 0.004). Furthermore, creatinine and ammonia levels decreased over time. Functional assessment demonstrated a reduced left atrial pressure ( p < 0.04) and a reduction of the required dobutamine dose to support myocardial function ( p < 0.003) in the hemofiltration group. Preserved cardiac function did not differ between groups. Hemofiltration results in an improved biochemical composition of the whole blood perfusate and preserves cardiac function better during normothermic perfusion based on a reduced left atrial pressure (LAP) and dobutamine requirement to support function.

Influence of the gene pool of the breed on the content and variability of copper in the liver of pigs

The average level and variability of copper in the liver of pigs of different breeds were studied. Samples of parenchymal organs from pigs were taken immediately after slaughter and analysed at the analytical centre for collective use of V.S. Sobolev Institute of Geology and Mineralogy of the Siberian Branch of the Russian Academy of Sciences using the method of atomic absorption spectrometry with flame and electrothermal atomisation on the SOLAAR M6 spectrometer (USA) by GOST 26929-94 Raw materials and food products— sample preparation Mineralization to determine the content of toxic elements. A normal distribution of the trait was found only in the Landrace breed (W = 0.94). In pig breeding areas, the content of heavy metals in soil, water and feed was studied, which did not exceed the maximum permissible concentration. The most significant variability of the microelement was observed in the Kemerovo breed, the least - in the Landrace breed. The full copper content was marked in the early ripening meat breed and the minimum in the Landrace breed. A smaller interquartile range about the Kemerovo and early meat breeds characterised the level of copper in the liver of Landrace pigs.

Genome-wide association study using a single-step approach for teat number in Duroc, Landrace and Yorkshire pigs in Korea.

We investigated the genetic basis of teat number in sows, which is an important factor in their reproductive performance. We collected genotyping data from 20 353 pigs of three breeds (Duroc, Landrace and Yorkshire) using the Porcine SNP60K Bead Chip, and analyzed phenotypic data from 240 603 pigs. The heritability values of total teat number were 0.33 ± 0.02, 0.51 ± 0.01 and 0.50 ± 0.01 in Duroc, Landrace and Yorkshire pigs, respectively. A genome-wide association study was used to identify significant chromosomal regions associated with teat number in SSC7 and SSC9 in Duroc pig, SSC3, SSC7 and SSC18 in Landrace pig, and SSC7, SSC8 and SSC10 in Yorkshire pig. Among the markers, MARC0038565, located between the vertnin (VRTN) and synapse differentiation-inducing 1-like (SYNDIG1L) genes, showed the strongest association in the Duroc pig and was significant in all breeds. In Landrace and Yorkshire pigs, the most significant markers were located within the apoptosis resistant E3 ubiquitin protein ligase 1 (AREL1) and latent transforming growth factor beta-binding protein 2 (LTBP2) genes in SSC7, respectively. VRTN is a candidate gene regulating the teat number. Most markers were located in SSC7, indicating their significance in determining teat number and their potential as valuable genomic selection targets for improving this trait. Extensive linkage disequilibrium blocks were identified in SSC7, supporting their use in genomic selection strategies. Our study provides valuable insights into the genetic architecture of teat numbers in pigs, and helps identify candidate genes and genomic regions that may contribute to this economically important trait.

Weighted single-step genome-wide association study (WssGWAS) to reveal new candidate genes for productive traits of Landrace pig in Korea

Weighted single-step genome-wide association study (WssGWAS) to reveal new candidate genes for productive traits of Landrace pig in Korea

Nutrient digestibility and nitrogen balance in different pig breeds fed raw, sprouted, or roasted (Vigna unguiculata) diets

The study examined effects of feeding iso-nutrient (150 g CP, 17.3 MJ ME kg−1) raw (RCP), sprouted (SPC), or roasted (RSCP) cowpea diets to Windsnyer (W), Large White (LW) × Landrace (LR), and the 3-way crossbred (W × LW × LR) growing pigs. Diet dry matter (DM) digestibility was estimated using standard, 3-step (gastric, small intestines, colon) in vitro digestion. Dietary in vivo nutrient digestibility and nitrogen balance were evaluated using 3 weaned pigs of each genotype. Pigs were housed in individual metabolic cages. The diets were assigned to pigs in a 3 × 3 change-over factorial experiment within three balanced, 3 × 3 Latin squares. Feeding periods consisted of 7 days adaption + 5 days’ measurement of feed intake, and the total faecal and urine excretions. The SPC diet increased step 3 in vitro DM digestibility compared to RSCP (P < 0.05). Metabolic size-scaled feed consumption was higher on the RCP compared to the RSCP diet (P < 0.05). Cowpea processing reduced apparent DM and ash digestibility (P < 0.05). LW × LR pigs exhibited lower digestibility of ash and acid detergent fiber (ADF) compared to 3-way crossbred pigs (P < 0.05). Significant genotype-diet interactions were observed for nitrogen intake (P < 0.0001), digestible nitrogen (P = 0.043), urinary nitrogen output (P < 0.0001), faecal nitrogen output (P < 0.0001), total nitrogen excretion (P < 0.0001), and nitrogen retention (P < 0.001). The biological value of feed protein was higher for W pigs than 3-way crossbred pigs (P < 0.05). Genotype-diet interactions suggested unique digestive and, or metabolic adaptive traits in the utilization of the differently processed cowpeas, which need further investigation.

Beneficial Effects of Combined Use of Extracorporeal Membrane Oxygenation and Hypothermic Machine Perfusion in Porcine Donors after Cardiac Death for Liver Transplantation.

Grafts from donors after cardiac death (DCD) have greatly contributed to expanding the donor organ pool. This study aimed to determine the benefits of subnormothermic extracorporeal membrane oxygenation (ECMO) and hypothermic machine perfusion (HMP) in a porcine model of DCD liver. Female domestic crossbred Large Yorkshire and Landrace pigs weighing approximately 20 kg were used. The abdominal aorta and inferior vena cava were cannulated and connected to an ECMO circuit for in situ perfusion of the abdominal organs at 22 °C for 60 min, 45 min after cardiac death. The pigs were divided into the cold storage (CS) group (n = 3), where liver grafts were preserved at 4 °C, and the HMP group (n = 3), where liver grafts were preserved by HMP at 8-10 °C. After 4 h of preservation, liver function was evaluated using an isolated liver reperfusion model for 2 h. Although the difference was insignificant, the liver effluent enzyme levels in the HMP group were lower than those in the CS group. Furthermore, morphological findings showed fewer injured hepatocytes in the HMP group than in the CS group. The combined use of in situ subnormothermic ECMO and HMP was beneficial for the functional improvement of DCD liver grafts.

Morphology and morphometry of the ulnar nerve in the forelimb of pigs.

The knowledge of the morphology and morphometry of peripheral nerves is essential for developing neural interfaces and understanding nerve regeneration in basic and applied research. Currently, the most adopted animal model is the rat, even though recent studies have suggested that the neuroanatomy of large animal models is more comparable to humans. The present knowledge of the morphological structure of large animal models is limited; therefore, the present study aims to describe the morphological characteristics of the Ulnar Nerve (UN) in pigs. UN cross-sections were taken from seven Danish landrace pigs at three distinct locations: distal UN, proximal UN and at the dorsal cutaneous branch of the UN (DCBUN). The nerve diameter, fascicle diameter and number, number of fibres and fibre size were quantified. The UN diameter was larger in the proximal section compared to the distal segment and the DCBUN. The proximal branch also had a more significant number of fascicles (median: 15) than the distal (median: 10) and the DCBUN (median: 11) segments. Additionally, the mean fascicle diameter was smaller at the DCBUN (mean: 165 μm) than at the distal (mean: 197 μm) and proximal (mean: 199 μm) segments of the UN. Detailed knowledge of the microscopical structure of the UN in pigs is critical for further studies investigating neural interface designs and computational models of the peripheral nervous system.

A genomic estimated breeding value-assisted reduction method of single nucleotide polymorphism sets: a novel approach for determining the cutoff thresholds in genome-wide association studies and best linear unbiased prediction

ABSTRACT Traditionally, the p-value is the criterion for the cutoff threshold to determine significant markers in genome-wide association studies (GWASs). Choosing the best subset of markers for the best linear unbiased prediction (BLUP) for improved prediction ability (PA) has become an interesting issue. However, when dealing with many traits having the same marker information, the p-values’ themselves cannot be used as an obvious solution for having a confidence in GWAS and BLUP. We thus suggest a genomic estimated breeding value-assisted reduction method of the single nucleotide polymorphism (SNP) set (GARS) to address these difficulties. GARS is a BLUP-based SNP set decision presentation. The samples were Landrace pigs and the traits used were back fat thickness (BF) and daily weight gain (DWG). The prediction abilities (PAs) for BF and DWG for the entire SNP set were 0.8 and 0.8, respectively. By using the correlation between genomic estimated breeding values (GEBVs) and phenotypic values, selecting the cutoff threshold in GWAS and the best SNP subsets in BLUP was plausible as defined by GARS method. 6,000 SNPs in BF and 4,000 SNPs in DWG were considered as adequate thresholds. Gene Ontology (GO) analysis using the GARS results of the BF indicated neuron projection development as the notable GO term, whereas for the DWG, the main GO terms were nervous system development and cell adhesion.

Pharmacokinetics of Orbital Topotecan After Ophthalmic Artery Chemosurgery and Intravenous Infusion in the Swine Model.

Surgery, multiagent systemic chemotherapy, and radiation are used for patients with orbital retinoblastoma but are associated with unacceptable short- and long-term toxicity (including death). We studied orbital and systemic exposure of topotecan in the swine model after ophthalmic artery chemosurgery (OAC) and intravenous (IV) delivery. Landrace pigs (n = 3) underwent 30-minute OAC of topotecan (4 mg), and samples were serially obtained from the femoral artery and from a microdialysis probe inserted into the lateral rectus muscle sheath of the infused eye as a surrogate of the orbital irrigation. Animals were recovered, and, after a wash-out period, plasma and microdialysate samples from the contralateral eye were collected after a 30-minute IV infusion of topotecan (4 mg). Samples were quantified by high-performance liquid chromatography, and population pharmacokinetic analysis was conducted using MonolixSuite. After OAC, median topotecan exposure in the orbit was 5624 ng × h/mL (range 3922-12531) compared to 23 ng × h/mL (range 18-75) after IV infusion. Thus, topotecan exposure in the orbit was 218-fold (range 75-540) higher after OAC than after IV infusion despite comparable systemic exposure (AUCpl) between routes (AUCpl, OAC: 141 ng × h/mL [127-191] versus AUCpl, IV: 139 ng × h/mL [126-186]). OAC was more selective to target the orbit because the median (range) orbital-to-plasma exposure ratio was 44 (28-65) after OAC compared to 0.18 (0.13-0.40) after IV infusion. OAC of topotecan resulted in higher orbital exposure than after IV infusion and was a more selective route for local drug delivery. Patients with orbital retinoblastoma may benefit from a multimodal treatment strategy including OAC therapy.

Multivariate genome-wide associations for immune traits in two maternal pig lines

BackgroundImmune traits are considered to serve as potential biomarkers for pig’s health. Medium to high heritabilities have been observed for some of the immune traits suggesting genetic variability of these phenotypes. Consideration of previously established genetic correlations between immune traits can be used to identify pleiotropic genetic markers. Therefore, genome-wide association study (GWAS) approaches are required to explore the joint genetic foundation for health biomarkers. Usually, GWAS explores phenotypes in a univariate (uv), trait-by-trait manner. Besides two uv GWAS methods, four multivariate (mv) GWAS approaches were applied on combinations out of 22 immune traits for Landrace (LR) and Large White (LW) pig lines.ResultsIn total 433 (LR: 351, LW: 82) associations were identified with the uv approach implemented in PLINK and a Bayesian linear regression uv approach (BIMBAM) software. Single Nucleotide Polymorphisms (SNPs) that were identified with both uv approaches (n = 32) were mostly associated with immune traits such as haptoglobin, red blood cell characteristics and cytokines, and were located in protein-coding genes. Mv GWAS approaches detected 647 associations for different mv immune trait combinations which were summarized to 133 Quantitative Trait Loci (QTL). SNPs for different trait combinations (n = 66) were detected with more than one mv method. Most of these SNPs are associated with red blood cell related immune trait combinations. Functional annotation of these QTL revealed 453 immune-relevant protein-coding genes. With uv methods shared markers were not observed between the breeds, whereas mv approaches were able to detect two conjoint SNPs for LR and LW. Due to unmapped positions for these markers, their functional annotation was not clarified.ConclusionsThis study evaluated the joint genetic background of immune traits in LR and LW piglets through the application of various uv and mv GWAS approaches. In comparison to uv methods, mv methodologies identified more significant associations, which might reflect the pleiotropic background of the immune system more accurately. In genetic research of complex traits, the SNP effects are generally small. Furthermore, one genetic variant can affect several correlated immune traits at the same time, termed pleiotropy. As mv GWAS methods consider strong dependencies among traits, the power to detect SNPs can be boosted. Both methods revealed immune-relevant potential candidate genes. Our results indicate that one single test is not able to detect all the different types of genetic effects in the most powerful manner and therefore, the methods should be applied complementary.

SP3.6 Does a novel preservation solution improve organ performance in an ex-vivo perfusion of porcine liver?

Abstract Aims This project aims to compare LS-A (Leeds solution for abdomen) to a gold standard solution, IGL-1 (Institute George-Lopez solution) at clinically acceptable CIT (Cold ischaemic time) in a DCD (Donation after cardiac death) model of porcine liver transplant. An ex-vivo Perfusion device will then provide normothermic machine perfusion to simulate the immediate post-transplant stage. Methods DCD livers retrieved from landrace pigs, were preserved at 4-hours CIT in LS-A or IGL-1. They were re-perfused on a normothermic machine perfusion device, using autologous blood as a perfusate. Biochemical analysis was performed hourly for various markers of tissue and hepatocyte damage. Results Livers stored in LS-A (n=6) and IGL-1 (n=6) have no significant differences when compared for ALT, AST, ALP, LDH and glucose. Perfusate lactate was significantly lower in the LS-A group (p=0.008) as was the perfusate potassium(p=0.001) across the perfusion period. Conclusions Analysis has shown significantly lower lactate and potassium in LS-A preserved livers, in DCD retrieval, with 4-hours CIT. There are no other observed significant differences between LS-A and IGL-1 when comparing liver function tests and LDH production. This suggests better tissue preservation with LS-A in the setting of very high risk donor livers. The next stage of the project will look at LS-A vs IGL-1 in an extended preservation period (&amp;gt;14 hours) in a DBD (Donation after brainstem death) model.

Three-Dimensional Printing of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] Biodegradable Scaffolds: Properties, In Vitro and In Vivo Evaluation.

The results of constructing 3D scaffolds from degradable poly(3-hydrosbutyrpate-co-3-hydroxyvalerate) using FDM technology and studying the structure, mechanical properties, biocompatibility in vitro, and osteoplastic properties in vivo are presented. In the process of obtaining granules, filaments, and scaffolds from the initial polymer material, a slight change in the crystallization and glass transition temperature and a noticeable decrease in molecular weight (by 40%) were registered. During the compression test, depending on the direction of load application (parallel or perpendicular to the layers of the scaffold), the 3D scaffolds had a Young's modulus of 207.52 ± 19.12 and 241.34 ± 7.62 MPa and compressive stress tensile strength of 19.45 ± 2.10 and 22.43 ± 1.89 MPa, respectively. SEM, fluorescent staining with DAPI, and calorimetric MTT tests showed the high biological compatibility of scaffolds and active colonization by NIH 3T3 fibroblasts, which retained their metabolic activity for a long time (up to 10 days). The osteoplastic properties of the 3D scaffolds were studied in the segmental osteotomy test on a model defect in the diaphyseal zone of the femur in domestic Landrace pigs. X-ray and histological analysis confirmed the formation of fully mature bone tissue and complete restoration of the defect in 150 days of observation. The results allow us to conclude that the constructed resorbable 3D scaffolds are promising for bone grafting.

CYP24A1 is associated with fetal mummification in pigs

Mummified piglets are among the leading causes of fertility loss and severely hamper reproductive performance in pigs. However, the contributions of genomic variation to the emergence of mummified piglets (MUM) have rarely been studied. This study aims to (1) elucidate the genetic architecture of MUM in sows of parity 1 - 3 using a single-step genome-wide association study (ssGWAS). The ssGWAS involved genotyping-by-sequencing of Large White and Landrace pig breeds. (2) Explore the biological role of the candidate genes at the cellular level. A total of 185 and 48 genome-wide significant SNPs are associated with MUM in Large White and Landrace pigs, explaining 0.01–36.52% genetic variance for different significant loci, respectively. All the significant SNPs are parity-specific, and the numerous, consecutive significant loci likely generated the nine significant peaks in different parities. Multiple candidate genes (including CYP24A1, FBXO30, and ARHGEF28) are associated with fetal congenital and maternal diseases. Collectively, CYP24A1 regulation contributes to steady-state levels of embryo development genes. CYP24A1 is involved in reproduction and, immune and gestational disorders. Thus, it is associated with known newborn death traits and MUM in Large White sows. Altogether, these results improve the current understanding of the genetic architecture of MUM and expand the knowledge on genetic variations for selecting against mummified piglets in pig breeding.

Development of the Acellular Dermal Matrix and Experimental Substantiation of Its Use in the Anterior Abdominal Wall hernia Repair

Objective: To develop a biological implant that is an acellular dermal matrix (ADM), evaluate its use as a support material in tensionfree hernioplasty for ventral hernia, and compare it to that of the commercially available implant PermacolTM. Materials and methods: ADM was derived from the porcine dermis (Landrace breed) decellularized using detergents and enzymes. The quality of devitalization was assessed in vitro. We performed sublay hernioplasty in 4-month-old Landrace pigs using ADM (experimental group) and PermacolTM (control group). The specimens were explanted on day 120 of the experiment for histological and immunohistochemical examination. Results: All cellular elements were removed by the detergent-enzymatic treatment of the dermis; the native architecture of the dermis was slightly disrupted. The specimens of the commercially available chemically cross-linked biomaterial PermacolTM had better mechanical properties than ADM specimens; however, there were no significant differences in terms of cytotoxicity. The state of the tissues after the explantation (number of fibroblasts and endothelial cells) showed no differences in the result of using ADM and PermacolTM. In 120 days, the materials integrated into the tissues without the formation of adhesions or inflammation. Conclusions: Our findings show that ADM does not have cytotoxic properties, has adequate biomechanical parameters to effectively reinforce supporting soft tissues, does not cause an inflammatory response during implantation, and integrates fully into tissues. Our study demonstrates the effectiveness and utility of the developed ADM in surgical treatment of anterior abdominal wall defects.

Differentially Expressed Genes in Response to a Squalene-Supplemented Diet Are Accurate Discriminants of Porcine Non-Alcoholic Steatohepatitis.

Squalene is the major unsaponifiable component of virgin olive oil, the fat source of the Mediterranean diet. To evaluate its effect on the hepatic transcriptome, RNA sequencing was carried out in two groups of male Large White x Landrace pigs developing nonalcoholic steatohepatitis by feeding them a high fat/cholesterol/fructose and methionine and choline-deficient steatotic diet or the same diet with 0.5% squalene. Hepatic lipids, squalene content, steatosis, activity (ballooning + inflammation), and SAF (steatosis + activity + fibrosis) scores were analyzed. Pigs receiving the latter diet showed hepatic squalene accumulation and twelve significantly differentially expressed hepatic genes (log2 fold change < 1.5 or <1.5) correlating in a gene network. These pigs also had lower hepatic triglycerides and lipid droplet areas and higher cellular ballooning. Glutamyl aminopeptidase (ENPEP) was correlated with triglyceride content, while alpha-fetoprotein (AFP), neutralized E3 ubiquitin protein ligase 3 (NEURL3), 2'-5'-oligoadenylate synthase-like protein (OASL), and protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B) were correlated with activity reflecting inflammation and ballooning, and NEURL3 with the SAF score. AFP, ENPEP, and PPP1R1B exhibited a remarkably strong discriminant power compared to those pathological parameters in both experimental groups. Moreover, the expression of PPP1R1B, TMEM45B, AFP, and ENPEP followed the same pattern in vitro using human hepatoma (HEPG2) and mouse liver 12 (AML12) cell lines incubated with squalene, indicating a direct effect of squalene on these expressions. These findings suggest that squalene accumulated in the liver is able to modulate gene expression changes that may influence the progression of non-alcoholic steatohepatitis.

The identification of blood pressure variation with hypovolemia based on the volume compensation method.

Objective: The purpose of this study is to identify the blood pressure variation, which is important in continuous blood pressure monitoring, especially in the case of low blood volume, which is critical for survival. Methods: A pilot study was conducted to identify blood pressure variation with hypovolemia using five Landrace pigs. New multi-dimensional morphological features of Photoplethysmography (PPG) were proposed based on experimental study of hemorrhagic shock in pigs, which were strongly correlated with blood pressure changes. Five machine learning methods were compared to develop the blood pressure variation identification model. Results: Compared with the traditional blood pressure variation identification model with single characteristic based on single period area of PPG, the identification accuracy of mean blood pressure variation based on the proposed multi-feature random forest model in this paper was up to 90%, which was 17% higher than that of the traditional blood pressure variation identification model. Conclusion: By the proposed multi-dimensional features and the identification method, it is more accurate to detect the rapid variation in blood pressure and to adopt corresponding measures. Significance: Rapid and accurate identification of blood pressure variation under low blood volume ultimately has the potential to effectively avoid complications caused by abnormal blood pressure in patients with clinical bleeding trauma.

Features of accumulation and variability of stable strontium in some organs and tissues of landrace pigs

The authors in the article demonstrated the results of assessing the level of stable strontium in the skeletal muscles, liver, kidneys and spleen of Landrace pigs at the end of the technological cycle. The studies were performed on clinically healthy animals raised in a large pig farm in the Altai Territory. The conditions of keeping the animals corresponded to those typical for meat fattening up to 100 kg. Feeding was carried out with complete feed. Elemental analysis of samples of parenchymal organs and muscle tissue was performed using inductively coupled plasma atomic emission spectral analysis. Data processing was performed using Microsoft Office Excel and the R programming language in the data analysis environment RStudio version 2022.07.2+576 (RStudio, PBC). The distribution did not correspond to normal in all cases. The dispersions are not homogeneous. Based on the mean value and median, an increasing ranked series of strontium content in organs and tissues were established: liver = skeletal muscles &lt; spleen &lt; kidneys, in numerical terms: 1: 1: 3.7: 4.7 and 1: 1: 3.9: 5.7 respectively. Medians for stable strontium in the liver, kidney, spleen, and skeletal muscle were 0.024; 0.130; 0.089 and 0.023 mg/kg, respectively. Reference intervals for the liver are 0.004-0.043 and for the spleen - 0.030-0.145 mg/kg. The most significant range of variability is characteristic of the kidneys of pigs. A considerable uniformity is typical of the liver and skeletal muscles. Using the Kruskal-Wallis test, it was established that the accumulation of stable strontium significantly differs in the examined organs and tissues of pigs (H = 68.9, df = 3, p &lt; 0.0001). Pairwise comparison showed significant differences for the kidney-liver, spleen-liver, skeletal muscle-kidney, and skeletal muscle-spleen pairs. Two clusters were identified according to the similarity of strontium accumulation: liver and skeletal muscles, kidneys and spleen. The calcium-strontium ratio, taking into account medians, for skeletal muscles was 1:1833, and for the liver - 1:1870. The established results can serve as an approximate physiological norm for the concentration of stable strontium in individual structures of the organism of Landrace pigs under the conditions of Western Siberia.

Genetic architecture of reproductive traits in Russian Landrace pigs

Relevance. Currently, the development of molecular and population genetics is a relevant task. The need to identify reliable candidate genes is associated with increase in pig population and quality improvement of both breeding and meat products. In this regard, the whole-genome analysis method solves issues of the genetic determination in quantitative and economically important traits.Methods. In this study, the GWAS method was applied to reproductive traits of Landrace sows.Results. 35 reliable candidate genes with biological functionality were identified and described, located near or within the identified significant SNP, responsible for various reproductive traits of sow organisms. Genes were classified into two clusters — 20 genes belonged to Cluster 1, which was responsible for mitochondrial and coupled electron transport, ATP synthesis, as well as binding of fatty acids and tryptophan (AFF4, IL13, IL4, IRF1, SHROOM1, IL-5, UQCRQ, MRPL13, TTR, ENPEP, NOL4, PCDH7, DSG3, RASSF6, ALB, AFP, ANKRD17, SOX9), and 15 genes belonged to Cluster 2, which was associated with response to bacterial and viral infections (YTHDC2, KIF3A, EYA1, DSG2, DSG4, PPIH, RNF125, TRAPPC8, PITX2, KIAA1462, MTPAP, JMJD6, METTL23, SRSF2, and U2AF1).

Swine Partial Liver Transplantation Model for Practicing Living Donor Liver Transplantation Based on a New Liver Segmentation Method.

Living donor liver transplantation (LDLT) is one of the most technically demanding and complicated procedures. However, unlike deceased donor liver transplantation, there is no suitable animal model for practicing LDLT. Herein, we propose a new liver segmentation method and a feasible pig LDLT model for practicing for LDLT in humans. Four Landrace pigs weighing 25, 25, 27, and 28 kg were used as donors and recipients to establish a partial liver transplantation model. Partial liver transplantation was performed using a right liver and a left liver, respectively, based on a new segmentation system compatible with that of humans. We established a new segmentation system for porcine liver transplantation and a partial liver transplantation model. For right liver transplantation, 91 and 142 min were required to operate on the donor and recipient, respectively; for left liver transplantation, 57 and 104 min were required to operate on the donor and recipient, respectively. All pigs that underwent partial liver transplantation remained alive until the operation was completed. It is expected that this new pig model based on the new segmentation system will be suitable as an educational tool for LDLT training and will replace the existing animal models for partial liver transplantation.

Surgical technique for explantation of a functioning cardiopulmonary complex in an experiment

Objective: to develop and approve the surgical technique for explantation of a functioning cardiopulmonary complex under normothermic autoperfusion.Materials and methods. Landrace pigs were used as the experimental model for a series of acute experiments (n = 10). During the experiment, invasive pressure in the cavities of the heart and main arteries, blood gas composition, and myocardial contractility were monitored. The functioning cardiopulmonary complex was explanted through a median sternotomy. The explanted complex was conditioned at 37–38 °C for 6 hours.Results. In the course of a series of experiments, it was shown that stable operation of the isolated heart-lung complex ex vivo for 6 hours was fundamentally possible provided that the parameters of the basic homeostasis constants are maintained. The technological solutions used made it possible to ensure safe hemodynamic and anatomical isolation of the working cardiopulmonary complex.Conclusion. The developed protocol for isolating a functioning cardiopulmonary complex allows to provide stable graft function for 6 hours under normothermic autoperfusion. Implementation of this concept in the development of transport systems would significantly facilitate their design and eliminate the use of expensive components. This would contribute to widespread introduction into clinical practice.