Search

ABSTRACT Introduction Methods Results Discussion Conclusion Intracardiac echocardiography (ICE) is an essential imaging modality for electrophysiology procedures, allowing intraprocedural monitoring, real‐time catheter manipulation guidance, and visualization of complex anatomic structures. Four‐dimentional (4D) ICE is the next stage in the evolution of the technology, permitting 360° rotation of the imaging plane, simultaneous multiplanar imaging, and volumetric acquisition, similar to transesophageal echocardiography (TEE). In this study, we report our experience with a novel 4D ICE catheter (NuVision, Biosense Webster) in structural electrophysiology procedures and difficult ventricular ablations in a swine preclinical model.7 Yorkshire swine underwent 4D ICE (NuVision, Biosense Webster) imaging procedures and anatomical shells of the RV, LV, and LA were created on the CARTO mapping system. Ablation was performed on the RV moderator band and LV papillary muscles under imaging guidance with the 4D ICE catheter. Additional ICE images were obtained of the LAA to simulate placement of a left atrial appendage occlusion (LAAO) device. Triphenyl tetrazolium chloride was administered before euthanasia and hearts were harvested, fixed in formalin, and sectioned.CARTOSOUND reconstruction was completed using the novel multiplane imaging software platform, allowing for creation of anatomy with minimal movement of the ICE catheter. Maps generated were similar to 3D reconstruction acquired in pre‐procedure CT. Ablation lesions were successfully delivered to the LV papillary muscles and RV moderator band with excellent correlation between gross pathology, electroanatomic mapping (EAM), and ICE images. 2D, multiplane, and 3D volumetric images were obtained of the LAA with minimal catheter movement to simulate use for an LAAO procedure.Intracardiac ultrasound has become an essential tool in the electrophysiology lab, especially for visualization of intracardiac structures in real time. 4D ICE is the natural progression of this technology, adding features previously only seen on TEE probes. In this preclinical study, 4D ICE was used to create CARTOSOUND shells with less catheter manipulation, which could decease procedural times and potentially decrease complications related to frequent manipulation of the ICE catheter. It was also placed in the left atrium to acquire multiplane and 3D rendered volumes of the left atrial appendage (LAA) similar to what would be required for an LAA occlusion procedure. This could be used as an alternative to TEE in LAAO procedures, potentially improving procedural efficiency and negating the need for general anesthesia. Additionally, it was used for real‐time ablation guidance, specifically directly on the RV moderator band and LV papillary muscles. Multiplanar imaging allowed for more accurate catheter visualization and localization when targeting these complex 3D intracavitary structures.4D ICE is the next stage in evolution of an essential imaging modality for electrophysiology procedures. Integration within the electroanatomical mapping system software platform may provide additional value for guiding ablation of challenging intracavitary structures and is a novel feature of the NuVision catheter. Through promising, this technology is new and further clinical investigation will be required to determine the ideal applications for its use. [ABSTRACT FROM AUTHOR]

Feed efficiency (FE) in pigs is an important factor in the profitability of pig farming operations. It refers to the ability of a pig to convert the feed it consumes into body weight. We used two metrics to measure FE: feed conversion ratio and average daily residual feed intake. A previous genome‐wide association study and transcriptome study in crossbred pigs identified two QTL regions on SSC9 associated with residual feed intake and pointed out two candidate genes of interest: (a) the gene encoding the Aryl Hydrocarbon Receptor gene (AHR) transcription factor; and (b) the Dynein, Axonemal, Heavy Polypeptide 11 gene (DNAH11). The previous study identified missense mutations in both genes leading to a conservative substitution of glycine to cysteine in AHR (AHR_rs339939442) and two non‐conservative substitutions in DNAH11, where arginine is replaced by threonine (DNAH11_rs325475644) and alanine is replaced by threonine (DNAH11_rs346074031). We have now genotyped the missense mutations in independent cohorts of 107 Duroc, 155 Landrace and 160 Yorkshire pigs to substantiate further if these variants directly impact FE‐related phenotypes. We verified that allele T of AHR_rs339939442 in AHR improves FE in Yorkshire pigs. Genotype GG of AHR_rs339939442 was fixed in Duroc pigs. We also confirmed that the variants rs325475644 and rs346074031 in DNAH11 did not affect FE. The findings contribute valuable insights into the genetic mechanisms governing FE in pigs, potentially offering contributions for future enhancements of FE. [ABSTRACT FROM AUTHOR]

BACKGROUND: We previously demonstrated that Shaziling and Yorkshire pigs differ in growth rate and meat quality. However, the molecular mechanisms responsible for such phenotypic differences remain unclear. In the present study, we performed a transcriptomic analysis of 36 longissimus dorsi (LM) and 36 soleus (SM) muscle samples from Shaziling and Yorkshire pigs at six postnatal stages (30, 60, 90, 150, 210 and 300 days) to explore the differences in postnatal skeletal muscle of Shaziling and Yorkshire pigs. RESULTS: Muscle morphological changes and the number of differentially expressed genes indicated the two stages of 60–90 days and 150–210 days were critical for the muscle growth and development in Shaziling pigs. Genes such as FLNC, COL1A1, NRAP, SMYD1, TNNI3, CRYAB and PDLIM3 played vital roles in the muscle growth, and genes such as CCDC71L, LPIN1, CPT1A, UCP3, NR4A3 and PDK4 played dominant roles in the lipid metabolism. Additionally, in contrast to the LM, the percentage of slow‐twitch muscle fibers in the SM of both breeds consistently decreased from 30 to 150 days of age, but there was a significant rebound at 210 days of age. However, the percentage of slow‐twitch muscle fibers in the SM of Shaziling pigs was higher than that in Yorkshire pigs, which may be associated with the calcium signaling pathway and the PPARβ/δ signaling pathway. CONCLUSION: The present study detected two critical periods and many functional genes for the muscle growth and development of Shaziling pigs, and showed differences in muscle fiber characteristics between Shaziling and Yorkshire pigs. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The present study investigated factors associated with the incidence of stillbirth in young hyper‐prolific sows within free farrowing systems in tropical environments. A total of 714 live‐born and 54 stillborn piglets from 57 Landrace × Yorkshire sows, with an average parity of 2.7 ± 1.0 (range: 1 – 4), were comprehensively investigated. Reproductive variables of the sows, including gestation length, farrowing duration, the total number of piglets born per litter, and the birth order and status of each piglet, were recorded. Differences in the physiological characteristics of live‐born and stillborn piglets, such as birth interval, cumulative birth interval, body weight at birth, crown‐rump length, body mass index (BMI), ponderal index (PI), meconium staining score, and the percentage of piglets with a broken umbilical cord, were analysed. Piglets were divided into four groups based on the quartiles of birth order (Q1–Q4). On average, the duration of farrowing was 173.3 ± 85.9 min, and the total number of piglets born and number of piglets born alive‐per litter were 14.1 ± 3.8 and 12.5 ± 3.5, respectively. The incidence of stillbirth was 6.7% (54/801 piglets). The higher percentages of stillbirths were detected in sows with large litter sizes (≥17 piglets, 10.9%) compared to those with small (≤13 piglets, 6.1%) and moderate (14 – 16 piglets, 2.8%) litter sizes (p <.001). The incidences of stillbirth in Q3 and Q4 of the litters were higher than in Q1 and Q2 (p <.001). Compared to live‐born piglets, stillborn piglets had higher cumulative birth interval (103.0 ± 3.71 vs. 142.4 ± 9.35 min, p <.001), BMI (17.1 ± 0.15 vs. 18.4 ± 0.39 kg/m2, p =.002), PI (63.7 ± 0.59 vs. 70.8 ± 1.59 kg/m3, p <.001), meconium staining scores (1.78 ± 0.04 vs. 2.04 ± 0.10, p =.021), and the percentage of piglets born with a ruptured umbilical cord (45.2% vs. 66.0%, p =.004). An increase in the incidence of stillbirth was detected at 60, 120, 150, 180, and ≥ 210 min after the first piglet was born, compared to those born within the first 30 min of farrowing (p <.05). In conclusion, the study found that stillbirths in young, hyper‐prolific sows were linked to several factors: large litter sizes (≥17 piglets per litter), prolonged cumulative birth intervals (142.4 min), elevated BMI of 18.4 kg/m2, high PI values of 70.8 kg/m3, increased meconium staining scores, and a higher occurrence of ruptured umbilical cords. To reduce the risk of stillbirth, particularly among piglets with high body indices born later in the birthing process, it is recommended to enhance farrowing supervision for young sows, starting at a cumulative birth interval of 60 min. [ABSTRACT FROM AUTHOR]

Restoring ischaemic myocardial tissue perfusion is crucial for minimizing infarct size. Acute mechanical left ventricular (LV) support has been suggested to improve infarct tissue perfusion. However, its regulatory mechanism remains unclear. We investigated the physiological mechanisms in six Yorkshire pigs, which were subjected to 90‐min balloon occlusion of the left anterior descending artery. During the acute reperfusion phase, LV support using an Impella heart pump was initiated. LV pressure, coronary flow and pressure of the infarct artery were simultaneously recorded to evaluate the impact of LV support on coronary physiology. Coronary wave intensity was calculated to understand the forces regulating coronary flow. Significant increases in coronary flow velocity and its area under the curve were found after mechanical LV support. Among the coronary flow‐regulating factors, coronary pressure was increased mainly during the late diastolic phase with less pulsatility. Meanwhile, LV pressure was reduced throughout diastole resulting in significant and consistent elevation of coronary driving pressure. Interestingly, the duration of diastole was prolonged with LV support. In the wave intensity analysis, the duration between backward suction and pushing waves was extended, indicating that earlier myocardial relaxation and delayed contraction contributed to the extension of diastole. In conclusion, mechanical LV support increases infarct coronary flow by extending diastole and augmenting coronary driving pressure. These changes were mainly driven by reduced LV diastolic pressure, indicating that the key regulator of coronary flow under mechanical LV support is downstream of the coronary artery, rather than upstream. Our study highlights the importance of LV diastolic pressure in infarct coronary flow regulation. Key points: Restoring ischaemic myocardial tissue perfusion is crucial for minimizing infarct size. Although mechanical left ventricular (LV) support has been suggested to improve infarct coronary flow, its specific mechanism remains to be clarified.LV support reduced LV pressure, and elevated coronary pressure during the late diastolic phase, resulting in high coronary driving pressure.This study demonstrated for the first time that mechanical LV support extends diastolic phase, leading to increased infarct coronary flow.Future studies should evaluate the correlation between improved infarct coronary flow and resulting infarct size. [ABSTRACT FROM AUTHOR]

Small animal models have shown improved cardiac function with DPP-4 inhibition, but many human studies have shown worse outcomes or no benefit. We seek to bridge the gap by studying the DPP-4 inhibitor sitagliptin in a swine model of chronic myocardial ischemia using proteomic analysis. Thirteen Yorkshire swine underwent the placement of an ameroid constrictor on the left coronary circumflex artery to model chronic myocardial ischemia. Two weeks post-op, swine received either sitagliptin 100 mg daily (SIT, n = 5) or no drug (CON, n = 8). After 5 weeks of treatment, swine underwent functional measurements and tissue harvest. In the SIT group compared to CON, there was a trend towards decreased cardiac index (p = 0.06). The non-ischemic and ischemic myocardium had 396 and 166 significantly decreased proteins, respectively, in the SIT group compared to CON (all p < 0.01). This included proteins involved in fatty acid oxidation (FAO), myocardial contraction, and oxidative phosphorylation (OXPHOS). Sitagliptin treatment resulted in a trend towards decreased cardiac index and decreased expression of proteins involved in OXPHOS, FAO, and myocardial contraction in both ischemic and non-ischemic swine myocardium. These metabolic and functional changes may provide some mechanistic evidence for outcomes seen in clinical studies. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The reliable function in vivo of self‐powered implantable bioelectric devices (iBEDs) requires biocompatible, seamless, effective interactions with biological tissues. Herein, an implantable tissue‐adhesive piezoelectric soft sensor (TPSS), in which the piezoelectric sensor converts biomechanical signals into electrical signals, and the adhesive hydrogel (AH) strengthens this conversion by seamlessly adhering the sensor on the wet and curvilinear surface, is proposed. The optimized AH exhibits strong adhesion to various organic or inorganic surfaces, including six commonly used engineering materials and three biological tissues. As a pressure sensor, TPSS proves good in vitro electrical performance with a high output of 8.3 V, long‐term stability of over 6000 cycles, and high energy power density of 186.9 µW m−2. In a large animal experiment, TPSS seamlessly adheres to the right‐side internal carotid artery of a Yorkshire pig to monitor blood pressure during a surgical operation. Compared to commercial sensors that work by inserting into tissues, TPSS does not cause any damage and can be peeled off after service. The integration of adhesive hydrogel and self‐powered pressure sensors enables biocompatible, seamless, and more efficient interactions between the biological system and iBEDs, which also contributes to next‐generation implantable bioelectronics with features of battery‐free, intelligent, and accurate. [ABSTRACT FROM AUTHOR]

Excreta traits comprise a very important characteristic in breeding that have been neglected for a long time. With the growth of intensive pig farming, plenty of environment problems have been raised, and people have begun to pay attention to pig excreta behaviors from genetics and breeding perspectives. However, the genetic architecture of excreta traits remains unclear. To investigate the genetic architecture of excreta traits in pigs, eight excreta traits and feed conversion ratio (FCR) were analyzed in this study. We performed genome‐wide association studies (GWASs) on 213 Yorkshire pigs and estimated genetic parameters for a total number of 290 pigs, comprising 213 Yorkshire, 52 Landrace and 25 Duroc. After analysis, eight and 22 genome‐wide significant SNPs were detected for FCR and the eight excreta traits in single‐trait GWASs separately, and 18 were detected in a multi‐trait meta‐analysis for excreta traits, six of which were detected in both the single‐trait and the multi‐trait GWAS. Eighty, 182 and 133 genes were detected within 1 Mb of the genome‐wide significant SNPs for FCR, excreta traits and multi‐trait meta‐analysis, respectively. Five candidate genes (BCKDC, DBT, ANKRD7, SHPRH and HCRT) with biochemical and physiological effects relevant to feed efficiency and excreta traits might be interesting markers for future breeding. Meanwhile, functional enrichment analysis indicates that most of the significant pathways are associated with the glutathione catabolic process, DNA topological change and replication fork protection complex. This study reveals the architecture of excreta traits in commercial pigs and offers an opportunity for decreasing the pollution from excreta using genomic selection in pigs. [ABSTRACT FROM AUTHOR]

Dipeptidyl peptidase 4 inhibitors (DPP4i) may be cardioprotective based on several small animal and clinical studies, though randomized control trials have demonstrated limited benefit. Given these discrepant findings, the role of these agents in chronic myocardial disease, particularly in the absence of diabetes, is still poorly understood. The purpose of this study was to determine the effects of sitagliptin, a DPP4i, on myocardial perfusion and microvessel density in a clinically relevant large animal model of chronic myocardial ischemia. Normoglycemic Yorkshire swine underwent ameroid constrictor placement to the left circumflex artery to induce chronic myocardial ischemia. Two weeks later, pigs received either no drug (CON, n = 8) or 100 mg oral sitagliptin (SIT) daily (n = 5). Treatment continued for 5 weeks, followed by hemodynamic measurements, euthanasia, and tissue harvest of ischemic myocardium. There were no significant differences in myocardial function between CON and SIT as measured by stroke work (p > 0.5), cardiac output (p = 0.22), and end‐systolic elastance (p = 0.17). SIT was associated with increased absolute blood flow at rest (17% increase, IQR 12–62, p = 0.045) and during pacing (89% increase, IQR 83–105, p = 0.002). SIT was also associated with improved arteriolar density (p = 0.045) compared with CON, without changes in capillary density (p = 0.72). SIT was associated with increased expression of pro‐arteriogenic markers MCP‐1 (p = 0.003), TGFß (p = 0.03), FGFR1 (p = 0.002), and ICAM‐1 (p = 0.03), with a trend toward an increase in the ratio of phosphorylated/active PLCγ1 to total PLCγ1 (p = 0.11) compared with CON. In conclusion, in chronically ischemic myocardium, sitagliptin improves myocardial perfusion and arteriolar collateralization via the activation of pro‐arteriogenic signaling pathways. [ABSTRACT FROM AUTHOR]

A 4‐year‐old American Yorkshire barrow (Sus scrofa domesticus) presented for masses on the left ventral palpebra and convex pinnae bilaterally. Multiple incisional biopsies were consistent with cutaneous squamous cell carcinoma. The pig was hospitalised for three sessions of electrochemotherapy, with intralesional bleomycin chemotherapy conducted over 1 month. No significant complications from the chemotherapy occurred. Long‐term follow‐up for newly developing lesions on the pinnae and periocular skin included treatment with CO2 laser and cryosurgery with success. Although squamous cell carcinoma is a common finding in food animals, methods other than humane euthanasia for long‐term management of this disease in pigs is poorly documented. Pigs are increasingly becoming popular pet animals, and veterinarians need to consider new modalities and treatment approaches for management of cutaneous neoplasms. This case report describes a comprehensive clinical workup, treatment and long‐term management of squamous cell carcinoma in a domesticated, pet American Yorkshire barrow not intended for food consumption. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the relationship between renal pelvis pressure and fluid absorption during ureteroscopy (URS) in a live porcine model. Materials and Methods: Flexible URS (fURS) was performed in anaesthetised female Yorkshire pigs. Prior to performing fURS, a 0.3556‐mm (0.014″) pressure‐sensing guidewire (Comet™, Boston Scientific) was placed to monitor renal pelvis pressure. A simulated fURS procedure was then performed for 1 h. Infusion of irrigation fluid (5% ethanol in saline) at target renal pelvis pressures (37–150 mmHg) was maintained for 1 h using a pressure bag and real‐time feedback from the pressure‐sensing guidewire. Venous blood was sampled every 10 min. The volume of irrigation fluid absorbed was estimated with established equations. Results: A URS procedure was performed in vivo in 18 porcine kidneys and the volume of irrigation fluid absorbed during the 1 h URS was calculated. The mean (SD) volume of irrigation fluid absorbed after 1 h of simulated URS was 7.6 (5.7), 10.8 (7.1), 26.0 (15.8), and 56.8 (22.3) mL at renal pelvis pressures of 37, 55, 75, and 150 mmHg, respectively. Compared with URS with renal pelvis pressure of 37 mmHg, the volume of fluid absorption was significantly greater at renal pelvis pressures of 75 and 150 mmHg (P = 0.026 and P = 0.047, respectively). In addition, compared with URS with renal pelvis pressure of 37 mmHg, the rate of absorption was significantly greater at renal pelvis pressures of 75 and 150 mmHg (both P < 0.001). Conclusion: In this study of an in vivo porcine model of URS, increasing renal pelvis pressures during URS were associated with increases in irrigation fluid absorption and increases in the rate of fluid absorption. [ABSTRACT FROM AUTHOR]

Left ventricular mechanical dyssynchrony (LVMD) refers to the nonuniformity in mechanical contraction and relaxation timing in different ventricular segments. We aimed to determine the relationship between LVMD and LV performance, as assessed by ventriculo‐arterial coupling (VAC), LV mechanical efficiency (LVeff), left ventricular ejection fraction (LVEF), and diastolic function during sequential experimental changes in loading and contractile conditions. Thirteen Yorkshire pigs submitted to three consecutive stages with two opposite interventions each: changes in afterload (phenylephrine/nitroprusside), preload (bleeding/reinfusion and fluid bolus), and contractility (esmolol/dobutamine). LV pressure–volume data were obtained with a conductance catheter. Segmental mechanical dyssynchrony was assessed by global, systolic, and diastolic dyssynchrony (DYS) and internal flow fraction (IFF). Late systolic LVMD was related to an impaired VAC, LVeff, and LVEF, whereas diastolic LVMD was associated with delayed LV relaxation (logistic tau), decreased LV peak filling rate, and increased atrial contribution to LV filling. The hemodynamic factors related to LVMD were contractility, afterload, and heart rate. However, the relationship between these factors differed throughout the cardiac cycle. LVMD plays a significant role in LV systolic and diastolic performance and is associated with hemodynamic factors and intraventricular conduction. [ABSTRACT FROM AUTHOR]

Purpose: There are no established criteria for discontinuing ex vivo normothermic limb perfusion (EVNLP) before irreversible damage occurs. This study evaluates weight gain as an indicator of injury during EVNLP. Methods: Sixteen Yorkshire pig forelimbs were procured and preserved using EVNLP with a hemoglobin‐based oxygen carrier (HBOC‐201) or static cold storage. EVNLP continued until termination criteria were met: arterial pressure ≥ 115 mm Hg, compartment pressure > 30 mm Hg, or 20% reduction of oxygen saturation. Limb weight, contractility, hemodynamics, perfusate electrolytes, metabolites and gases were recorded. Muscles were biopsied 6‐h, and muscle injury scores (MIS) calculated. Forearm compartment pressures and indocyanine green (ICG) angiography were recorded at endpoint. Outcomes were compared at 2%, 5%, 10%, and 20% limb weight gain. Results: EVNLP lasted 20 ± 3 h. Weight gain was observed after 13 ± 5 h (2%), 15 ± 6 h (5%), 16 ± 6 h (10%), and 19 ± 4 h (20%). Weight correlated positively with MIS (ρ = 0.92, p < 0.0001), potassium (ρ = −1.00, p < 0.0001), pressure (ρ = 0.78, p < 0.0001), and negatively with contractility (ρ = −0.96, p = 0.011). At 5% weight gain, MIS (p < 0.0001), potassium (p = 0.03), and lactate (p < 0.0001) were significantly higher than baseline. Median muscle contractility was 5 [3–5] at 2% weight gain, 4 [1–5] at 5%, 3 [0–4] and 2 [0–2] at 10% and 20%, respectively. At 20% weight gain, contractility was significantly lower than baseline (p = 0.003). Percent weight gain correlated negatively with endpoint ICG hoof fluorescence (r = −0.712, p = 0.047). Conclusions: Weight gain correlated with microscopic muscle injury and was the earliest evidence of limb dysfunction. Weight gain may serve as a criterion for discontinuation of EVNLP. [ABSTRACT FROM AUTHOR]

The annotation of animal genomes plays an important role in elucidating molecular mechanisms behind the genetic control of economically important traits. Here, we employed long‐read sequencing technology, Oxford Nanopore Technology, to annotate the pig transcriptome across 17 tissues from two Yorkshire littermate pigs. More than 9.8 million reads were obtained from a single flow cell, and 69 781 unique transcripts at 50 108 loci were identified. Of these transcripts, 16 255 were found to be novel isoforms, and 22 344 were found at loci that were novel and unannotated in the Ensembl (release 102) and NCBI (release 106) annotations. Novel transcripts were mostly expressed in cerebellum, followed by lung, liver, spleen, and hypothalamus. By comparing the unannotated transcripts to existing databases, there were 21 285 (95.3%) transcripts matched to the NT database (v5) and 13 676 (61.2%) matched to the NR database (v5). Moreover, there were 4324 (19.4%) transcripts matched to the SwissProt database (v5), corresponding to 11 356 proteins. Tissue‐specific gene expression analyses showed that 9749 transcripts were highly tissue‐specific, and cerebellum contained the most tissue‐specific transcripts. As the same samples were used for the annotation of cis‐regulatory elements in the pig genome, the transcriptome annotation generated by this study provides an additional and complementary annotation resource for the Functional Annotation of Animal Genomes effort to comprehensively annotate the pig genome. [ABSTRACT FROM AUTHOR]

BACKGROUND: Nursing mom can regulate the gut microbiome succession in offspring. However, it remains unclear whether these effects are long‐term and what effect it has on the growth performance of piglets. This study aimed to develop a cross‐fostering model of piglets and investigate the effect of maternal environment on gut microbiota, even the growth performance of the offspring, and if this effect could be maintained in the long term. RESULTS: Four groups of piglets were generated as follows (n = 12): Duroc piglets nursed by their birth mom (Dd) or Yorkshire sows (Yd), Yorkshire piglets nursed by Duroc sows (Dy) or their birth mom (Yy). The study found that cross‐fostering improved the growth performance of piglets for a long time. The gut microbiota of piglets was mainly determined by the breeds of nursing moms before weaning, and it was more and more influenced by their breeds after weaning, but the influence of birth mom breeds still existed. The linear discriminant analysis (LDA) effect size (LEfSe) analysis and Spearman correlation analysis showed that Sutterella, Butyricimonas and Alistipes, which were affected by nursing mom before weaning, had a strong positive correlation with the growth performance of piglets before weaning. Candidatus_Soleaferrea and Treponema, which were affected by both nursing mom and piglet breed after weaning, were significantly negatively correlated with the growth performance of piglets long after weaning. CONCLUSION: Our results revealed that both the breeds of piglets and their birth moms influence the gut microbiota of piglets for a long time, even after weaning. Additionally, this effect might be related to the growth performance of piglets. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Extracorporeal membrane oxygenation (ECMO) is an advanced medical technology used to treat respiratory and heart failure. The coronavirus pandemic has resulted in significantly more ECMO patients worldwide. However, the number of hospitals with ECMO capabilities and ECMO-trained staff are limited. Training of personnel in ECMO could supplement this demand. Objective: To evaluate our previously developed ECMO course using a task trainer-based training, as opposed to an existing live tissue-training model, and determine if such a program was adequate and could be expanded to other facilities. Methods: Seventeen teams, each consisting of a physician and nurse, underwent a 5 hour accelerated ECMO course in which they watched prerecorded ECMO training lectures, primed circuit, cannulated, initiated ECMO, and corrected common complications. Training success was evaluated via knowledge and confidence assessments and observation of each team attempting to initiate ECMO while troubleshooting complications on a Yorkshire swine. Results: Seventeen teams successfully completed the course. Sixteen teams (94%, 95% CI = 71%-100%) successfully placed the swine on veno-arterial ECMO. Of those 16 teams, 15 successfully transitioned to veno-arterial-venous ECMO. The knowledge assessments and confidence levels of physicians and nurses increased by 24.3% from pretest (mean of 65.3%, SD 14.4%) to posttest (mean of 89.6%, SD 10.3%), p < 0.0001. Conclusions: An abbreviated one day lecture and hands-on task trainer-based ECMO course resulted in a high rate of successful skill demonstration and improvement of physicians' and nurses' knowledge assessments and confidence levels, similar to our previous live tissue training program. [ABSTRACT FROM AUTHOR]

Acute right ventricular pressure overload (RVPO) occurs following congenital heart surgery and often results in low cardiac output syndrome. We tested the hypothesis that the RV exhibits limited ability to modify substrate utilization in response to increasing energy requirements during acute RVPO after cardiopulmonary bypass (CPB). We assessed the RV fractional contributions (Fc) of substrates to the citric acid cycle in juvenile pigs exposed to acute RVPO by pulmonary artery banding (PAB) and CPB. Sixteen Yorkshire male pigs (median 38 days old, 12.2 kg of body weight) were randomized to SHAM (Ctrl, n = 5), 2‐h CPB (CPB, n = 5) or CPB with PAB (PAB‐CPB, n = 6). Carbon‐13 (13C)‐labeled lactate, medium‐chain, and mixed long‐chain fatty acids (MCFA and LCFAs) were infused as metabolic tracers for energy substrates. After weaning from CPB, RV systolic pressure (RVSP) doubled baseline in PAB‐CPB while piglets in CPB group maintained normal RVSP. Fc‐LCFAs decreased significantly in order PAB‐CPB > CPB > Ctrl groups by 13C‐NMR. Fc‐lactate and Fc‐MCFA were similar among the three groups. Intragroup analysis for PAB‐CPB showed that the limited Fc‐LCFAs appeared prominently in piglets exposed to high RVSP‐to‐left ventricular systolic pressure ratio and high RV rate‐pressure product, an indicator of myocardial oxygen demand. Acute RVPO after CPB strongly inhibits LCFA oxidation without compensation by lactate oxidation, resulting in energy deficiency as determined by lower (phosphocreatine)/(adenosine triphosphate) in PAB‐CPB. Adequate energy supply but also metabolic interventions may be required to circumvent these RV energy metabolic abnormalities during RVPO after CPB. [ABSTRACT FROM AUTHOR]

Objectives: There is growing evidence that excess adipose tissue within the head and neck contributes to obstructive sleep apnea (OSA), particularly in obese patients. This subset of the population is often difficult to treat with surgical therapies. We theorized that a novel, transcervical method of injectable cryoablation using ice‐slurry can achieve low temperatures without causing neurovascular damage or airway distress in a swine model. Methods: Four Yorkshire pigs were injected with ice‐slurry comprised of normal saline and 10% glycerol cooled to −6°C via a transcervical, ultrasound guided approach. Direct laryngoscopy was used to confirm accurate placement of the slurry. Thermocouple placement at the needle‐tip was used to measure temperatures at injection site. Swine were monitored for clinical signs of tongue necrosis and airway edema for 2 months, and then euthanized. Twelve biopsy samples from the base of the tongue were collected for histology. These were assessed for presence of tissue damage, inflammation and collagen formation by a blinded board‐certified pathologist. Results: Tongue tissue temperature below 10°C was achieved for 13.5 ± 1.1 min. Minimum tissue temperature was −4 ± 0.6°C. There was no clinical or pathological evidence of tongue damage to include damage to the lingual nerve or artery. There was some histologic evidence of new collagen formation in areas of the tongue. Conclusions: Transcervical ultrasound‐guided ice‐slurry injection is feasible, well‐tolerated at temperatures previously shown to be capable of selectively targeting adipose tissue in the base of the tongue in a preclinical swine model, without causing neurovascular damage or airway distress when properly injected. [ABSTRACT FROM AUTHOR]

A 3‐month‐old, Yorkshire cross barrow was evaluated for diarrhoea and vomiting, which were observed intermittently during and after consumption of feed and water. Weight loss, despite good appetite, was also reported. Abdominal radiographs demonstrated stomach distention and gas within the duodenal lumen. Thickening of the pyloric antrum and proximal duodenum were noticed using abdominal ultrasonography. Esophageal endoscopy demonstrated severe reduction of the aborad esophageal lumen, which precluded endoscopic evaluation of the stomach. A severe esophageal stricture was diagnosed. Medical management using omeprazole and dietary changes did not alleviate the clinical signs. The esophageal stricture was successfully resolved by balloon dilation performed under general anaesthesia using fluoroscopy. The pig started to gain weight, developed normally, and was successfully harvested 3 months later. The balloon dilation was curative and is presented as an option for cases of severe porcine gastric ulceration and esophageal stricture that are refractory to nutritional and medical management. [ABSTRACT FROM AUTHOR]

Pediatric anterior cruciate ligament (ACL) injuries are on the rise, and females experience higher ACL injury risk than males during adolescence. Studies in skeletally immature patients indicate differences in ACL size and joint laxity between males and females after the onset of adolescence. However, functional data regarding the ACL and its anteromedial and posterolateral bundles in the pediatric population remain rare. Therefore, this study uses a porcine model to investigate the sex‐specific morphology and biomechanics of the ACL and its bundles throughout skeletal growth. Hind limbs from male and female Yorkshire pigs aged early youth to late adolescence were imaged using magnetic resonance imaging to measure the size and orientation of the ACL and its bundles, then biomechanically tested under anterior‐posterior drawer using a robotic testing system. Joint laxity decreased (p < 0.001) while joint stiffness increased (p < 0.001) throughout skeletal growth in both sexes. The ACL was the primary stabilizer against anterior tibial loading, while the functional role of the anteromedial bundle increased with age (p < 0.001), with an earlier increase in males. ACL and posterolateral bundle cross‐sectional area and ACL and anteromedial bundle length were larger in males than females during adolescence (p < 0.01 for all), while ACL and bundle sagittal angle remained similar between sexes. Additionally, in situ ACL stiffness versus cross‐sectional area regressions were significant across skeletal growth (r2 = 0.75, p < 0.001 in males and r2 = 0.64, p < 0.001 in females), but not within age groups. This study has implications for age and sex‐specific surgical intervention strategies and suggests the need for human studies. [ABSTRACT FROM AUTHOR]

Imprinted genes – exhibiting parent‐specific transcription – play essential roles in the process of mammalian development and growth. Skeletal muscle growth is crucial for meat production. To further understand the role of imprinted genes during the porcine skeletal muscle growth, DNA‐seq and RNA‐seq were used to explore the characteristics of imprinted genes from porcine reciprocal crosses. A total of 584 545 single‐nucleotide variations were discovered in the DNA‐seq data of F0 parents, heterozygous in two pig breeds (Yorkshire and Min pigs) but homozygous in each breed. These single‐nucleotide variations were used to determine the allelic‐specific expression in F1 individuals. Finally, eight paternal expression sites and three maternal expression sites were detected, whereas two paternally expressed imprinted genes (NDN and IGF2) and one maternally expressed imprinted gene (H1‐3) were validated by Sanger sequencing. DNA methylation regulates the expression of imprinted genes, and all of the identified imprinted genes in this study were predicted to possess CpG islands. PBX1 and YY1 binding motifs were discovered in the promoter regions of all three imprinted genes, which were candidate elements regulating the transcription of imprinted genes. For these identified imprinted genes, IGF2 and NDN promoted muscle growth whereas H1‐3 inhibited cell proliferation, corroborating the 'parental conflict' theory that paternally expressed imprinted genes assisted descendants' growth whereas maternally expressed imprinted genes inhibited it. This study discovered porcine imprinted genes in skeletal muscle and was the first to reveal that H1‐3 was expressed by the maternal allele to our knowledge. Our findings provided valuable resources for the potential utilization of imprinted genes in pig breeding. [ABSTRACT FROM AUTHOR]

Acute respiratory distress syndrome (ARDS) is a lung injury characterized by noncardiogenic pulmonary edema and hypoxic respiratory failure. The purpose of this study was to investigate the effects of therapeutic hypothermia on short‐term experimental ARDS. Twenty adult female Yorkshire pigs were divided into four groups (n = 5 each): normothermic control (C), normothermic injured (I), hypothermic control (HC), and hypothermic injured (HI). Acute respiratory distress syndrome was induced experimentally via intrapulmonary injection of oleic acid. Target core temperature was achieved in the HI group within 1 h of injury induction. Cardiorespiratory, histologic, cytokine, and metabolomic data were collected on all animals prior to and following injury/sham. All data were collected for approximately 12 h from the beginning of the study until euthanasia. Therapeutic hypothermia reduced injury in the HI compared to the I group (histological injury score = 0.51 ± 0.18 vs. 0.76 ± 0.06; p = 0.02) with no change in gas exchange. All groups expressed distinct phenotypes, with a reduction in pro‐inflammatory metabolites, an increase in anti‐inflammatory metabolites, and a reduction in inflammatory cytokines observed in the HI group compared to the I group. Changes to respiratory system mechanics in the injured groups were due to increases in lung elastance (E) and resistance (R) (ΔE from pre‐injury = 46 ± 14 cmH2O L−1, p < 0.0001; ΔR from pre‐injury: 3 ± 2 cmH2O L−1 s−, p = 0.30) rather than changes to the chest wall (ΔE from pre‐injury: 0.7 ± 1.6 cmH2O L−1, p = 0.99; ΔR from pre‐injury: 0.6 ± 0.1 cmH2O L−1 s−, p = 0.01). Both control groups had no change in respiratory mechanics. In conclusion, therapeutic hypothermia can reduce markers of injury and inflammation associated with experimentally induced short‐term ARDS. [ABSTRACT FROM AUTHOR]

The TNNC2 gene encodes the fast‐skeletal C subunit of the troponin complex that plays a vital role in the regulation of striated muscle contraction and could be a candidate gene for pork quality. Here, we identified coupled insertion/deletion (indel) variants, a 17‐bp insertion and an 11‐bp deletion, in porcine TNNC2. The coupled indel variants provide an alternative splicing donor site and cause a 42‐bp truncation in the first exon of TNNC2‐201, leading to increased expression of TNNC2‐201. Polymorphism of the two indel variants is associated with the average backfat thickness (p = 3.16 × 10−3), pH value 24 h post‐slaughter (p = 4.31 × 10−4), intramuscular fat (IMF) content (p = 1.54 × 10−2), and myofiber cross‐sectional area (p = 2.86 × 10−2) of longissimus dorsi in a population of 425 Duroc (♂) × Luchuan (♀) pigs. In an independent population of 1,304 commercial hybrid pigs, we further confirmed that it is associated with the IMF content (p = 1.75 × 10−4), pH value 45 min post‐slaughter (p = 6.34 × 10−3), and drip loss (p = 2.88 × 10−2) of the longissimus dorsi muscle. An increased frequency of the mutant allele is linked to increased IMF content, smaller myofibers, and a relatively moderate pH value. Furthermore, we detected a mutant allele frequency of 96.67% in Luchuan pigs and 86.67% in Tongcheng pigs, whereas the frequency was 0.91% in Duroc pigs, 2.04% in Landrace pigs, and 0% in Yorkshire and Pietrain pigs, indicating its opposing distributions in lean‐type and Chinese local pig breeds. The present results establish coupled indel variants of TNNC2 as a novel molecular marker for meat quality improvement. [ABSTRACT FROM AUTHOR]

BACKGROUND Essential oils (EOs) are extensively used in swine production because of their bioactive action in gut health. In addition, some EOs have the potential to reduce waste emission. The present study aimed to find an optimal combination of carvacrol, thymol and cinnamaldehyde to promote nitrogen utilization and reduce waste emission by a model in vitro and an animal study. RESULTS: In the study in vitro, various dosages of essential oils (EOs) were used to evaluate the effect on nitrogen metabolism through a three‐step model. Compared with other EO combinations, 2EO (10 ppm cinnamaldehyde and 20 ppm thymol), and 3EO (10 ppm cinnamaldehyde, 20 ppm thymol and 200 ppm carvacrol) displayed greater nitrogen digestibility, lesser ammonia production and lower activity of microbial enzymes. In the animal study, growing male Landrace × Yorkshire pigs (initial body weight: 31.8 ± 3.3 kg, n = 18) were randomly divided into three groups and fed the control, 2EO or 3EO diet for 4 weeks. Pigs fed 3EO exhibited the greatest nitrogen digestibility (85.4%, P < 0.05). EO supplementation decreased the emission of ammonia (130–140 vs. 223 mg g−1) and total fecal nitrogen (8.0–9.9 vs. 12.4 g d−1) (P < 0.05). Microbial protease and urease activities were inhibited by EO treatments (P < 0.01). Both 2EO and 3EO reduced the content of indole and 3‐methylindole (P < 0.01), whereas only 2EO caused a decrease in p‐cresol (P < 0.1). CONCLUSION: 2EO was suitable for reducing waste emission and odorous compounds in growing pigs, whereas 3EO was optimal for increasing nitrogen utilization and partially reducing waste odorous compounds. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: Piglet mortality is an economically important complex trait that impacts sow prolificacy. Genetic analyses for piglet mortality at weaning have been reported in dozens of studies, but not for piglet mortality at birth. In this study, we used multi‐breed data sets from Yorkshire, Landrace, and Duroc sows to characterize the genetic fundamentals of piglet mortality at birth. The heritabilities from parity I to III were estimated to be 0.0630, 0.1031, and 0.1140 respectively. By using a combined strategy, a total of 21 SNPs were detected in three parities, of which six were observed in parity I, five in parity II and 10 in parity III. Genome annotation revealed that these SNPs were harbored within or close to 19 candidate genes. The candidate genes were found to associate with the reproductive system and embryonic development in the tissue expression database, which are reasonably related to piglet mortality. These findings are expected to provide much information for understanding the genetic and genomic fundamentals of farrowing mortality. [ABSTRACT FROM AUTHOR]

Summary: We developed a high‐resolution and comprehensive typing method for swine leukocyte antigen 3 (SLA‐3), an MHC class I gene, employing locus‐specific genomic PCR followed by subsequent direct sequencing. A total of 292 individuals from nine pure, one cross‐breed and six cell lines were successfully typed. A total of 21 SLA‐3 alleles were identified, of which four were found to be novel alleles. However, the allelic diversity of SLA‐3 was lower than that of previously reported class I genes, SLA‐1 and ‐2. More SLA‐3 alleles were observed in the Landrace and Yorkshire breeds than the other breeds. SLA‐3*04:01 was identified in seven out of nine breeds and was the most widely distributed allele across all breeds. Therefore, the typing method reported in this study completes our efforts to develop high‐resolution typing methods for major SLA molecules, facilitating the combined analysis of major SLA genes from field samples, which is important to understand the relationship between the adaptive immune responses against pathogens and the immunogenetic makeup of an individual. [ABSTRACT FROM AUTHOR]

Background: Conventional bright‐blood late gadolinium enhancement (LGE) cardiac magnetic resonance imaging (MRI) often suffers from poor scar‐to‐blood contrast due to the bright blood pool adjacent to the enhanced scar tissue. Recently, a dark‐blood LGE method was developed which increases scar‐to‐blood contrast without using additional magnetization preparation. Purpose We aim to histopathologically validate this dark‐blood LGE method in a porcine animal model with induced myocardial infarction (MI). Study Type: Prospective. Animal Model: Thirteen female Yorkshire pigs. Field Strength/Sequence: 1.5 T, two‐dimensional phase‐sensitive inversion‐recovery radiofrequency‐spoiled turbo field‐echo. Assessment MI was experimentally induced by transient coronary artery occlusion. At 1‐week and 7‐week post‐infarction, in‐vivo cardiac MRI was performed including conventional bright‐blood and novel dark‐blood LGE. Following the second MRI examination, the animals were sacrificed, and histopathology was obtained. Matching LGE slices and histopathology samples were selected based on anatomical landmarks. Independent observers, while blinded to other data, manually delineated the endocardial, epicardial, and infarct borders on either LGE images or histopathology samples. The percentage of infarcted left‐ventricular myocardium was calculated for both LGE methods on a per‐slice basis, and compared with histopathology as reference standard. Contrast‐to‐noise ratios were calculated for both LGE methods at 1‐week and 7‐week post‐infarction. Statistical Tests: Pearson's correlation coefficient and paired‐sample t‐tests were used. Significance was set at P < 0.05. Results: A combined total of 24 matched LGE and histopathology slices were available for histopathological validation. Dark‐blood LGE demonstrated a high level of agreement compared to histopathology with no significant bias (−0.03%, P = 0.75). In contrast, bright‐blood LGE showed a significant bias of −1.57% (P = 0.03) with larger 95% limits of agreement than dark‐blood LGE. Image analysis demonstrated significantly higher scar‐to‐blood contrast for dark‐blood LGE compared to bright‐blood LGE, at both 1‐week and 7‐weeks post‐infarction. Data Conclusion: Dark‐blood LGE without additional magnetization preparation provides superior visualization and quantification of ischemic scar compared to the current in vivo reference standard. Level of Evidence: 1 Technical Efficacy Stage: 2 [ABSTRACT FROM AUTHOR]

Purpose: Magnetic susceptibility (Δχ) alterations have shown association with myocardial infarction (MI) iron deposition, yet there remains limited understanding of the relationship between relaxation rates and susceptibility or the effect of magnetic field strength. Hence, Δχ and R2∗ in MI were compared at 3T and 7T. Methods: Subacute MI was induced by coronary artery ligation in male Yorkshire swine. 3D multiecho gradient echo imaging was performed at 1‐week postinfarction at 3T and 7T. Quantitative susceptibility mapping images were reconstructed using a morphology‐enabled dipole inversion. R2∗ maps and quantitative susceptibility mapping were generated to assess the relationship between R2∗, Δχ, and field strength. Infarct histopathology was investigated. Results: Magnetic susceptibility was not significantly different across field strengths (7T: 126.8 ± 41.7 ppb; 3T: 110.2 ± 21.0 ppb, P = NS), unlike R2∗ (7T: 247.0 ± 14.8 Hz; 3T: 106.1 ± 6.5 Hz, P <.001). Additionally, infarct Δχ and R2∗ were significantly higher than remote myocardium. Magnetic susceptibility at 7T versus 3T had a significant association (β = 1.02, R2 = 0.82, P <.001), as did R2∗ (β = 2.35, R2 = 0.98, P <.001). Infarct pathophysiology and iron deposition were detected through histology and compared with imaging findings. Conclusion: R2∗ showed dependence and Δχ showed independence of field strength. Histology validated the presence of iron and supported imaging findings. [ABSTRACT FROM AUTHOR]

Summary: lncRNAs play crucial roles in fat metabolism in animals. Previously, we have compared the mRNA transcriptome profiles between seven fat‐type Chinese pig breeds and one lean‐type Western breed (Yorkshire, YY). The associations between differentially expressed (DE) genes and phenotypical traits were investigated. In the present study, to further explore the underlying regulatory mechanisms, lncRNAs were sequenced and compared between YY and Chinese indigenous breeds. The results showed 9114 and 7538 DE lncRNAs between at least one Chinese breed and the YY breed in the adipose and muscle tissue respectively. KEGG enrichment analysis revealed that the target genes of these DE lncRNAs mainly influenced the glucolipid metabolism, which is an important process affecting meat quality. Correlation analyses between the DE lncRNA and DE mRNA genes related to meat quality and growth traits were performed. The results showed that LTCONS_00073280 was associated with intramuscular fat content. Four lncRNAs (LTCONS_00101781, LTCONS_00037879, LTCONS_00088260 and LTCONS‐00128343) might mediate backfat thickness. Overall, this study provides candidate lncRNAs that potentially affect meat quality, which might be useful for molecular breeding of pig breeds in future. [ABSTRACT FROM AUTHOR]

Purpose: Development and validation of an animal model of labral healing would facilitate translation of novel surgical and biological strategies to improve glenolabral healing. The purpose of this study was to characterize the anatomic and histological properties of the shoulder labrum in rat, rabbit, dog, pig, goat, and humans. Given the demonstrated similarities in size and structural morphology in other joints, it was hypothesized that the goat glenoid with surrounding capsulolabral complex would most closely resemble that of humans in terms of dimensions and structure, as observed grossly and histologically. Methods: Cadaveric glenohumeral joints from rats (n = 8), New Zealand white rabbits (n = 13), Mongrel dogs (n = 9), Spanish goats (n = 10), Yorkshire pigs (n = 10), and humans (n = 9) were freshly harvested. Photographs were taken of the glenoid with its surrounding capsulolabral complex. Linear dimensions of the glenoid articular surface were measured. It was determined where the capsulolabral complex was continuous with, or recessed from, the articular glenoid surface. The glenoid was divided into 6 equal segments radiating out toward 12, 2, 4, 6, 8, and 10 o'clock positions. Samples were sectioned and stained with Safranin O/Fast green and Mallory Trichrome. Insertion of the capsulolabral tissue onto the glenoid was qualitatively assessed and compared with gross morphology. Results: Dimensions of the goat glenoid most closely paralleled dimensions of the human glenoid. A capsulolabral complex was continuous with the glenoid surface from ~ 9 to 12 o'clock in the rats, 7 to 12 o'clock in rabbits, 5 to 12 o'clock in the dogs, and 9 to 12 o'clock in goats, 6 to 12 o'clock in pigs, and 2 to 8 o'clock in humans. In contrast to humans, no other species demonstrated an organized fibrocartilaginous labrum either macroscopically or histologically. Conclusion: The animals in the present study did not possess a discrete fibrocartilaginous labrum by gross or histological evaluation, as directly compared to humans. While models using these animals may be acceptable for examining other shoulder pathologies, they are not adequate to evaluate labral pathology. Level of evidence: Basic Science Study; Anatomy and Histology; Cadaveric Animal Model. [ABSTRACT FROM AUTHOR]

Litter traits are important in the development of production and economic profits of pigs. The object of this study was to perform genome‐wide association studies (GWASs) for the total number born (TNB), number born alive (NBA) and number born healthy (NBH) traits in a Yorkshire population. By mixed model, we conducted GWASs with gcta software, and in total identified 3, 7 and 12 significant SNPs associated with TNB, NBA and NBH respectively: one on Sus scrofa chromosome (SSC) 2 (p = 7.03 × 10−5), one on SSC4 (p = 8.53 × 10−5), two on SSC 6 (p = 9.27 × 10−5 to 9.64 × 10−5), nine on SSC 8 (p = 1.53 × 10−5 to 8.52 × 10−5), four on SSC 14 (p = 2.17 × 10−5 to 6.79 × 10−5), and one on SSC 15 (p = 9.30 × 10−5). We screened for flanking regions ±1 Mb nearby or within the significant SNPs, and found 203 candidate genes, including 53 for TNB, 71 for NBA and 112 for NBH. In conclusion, our findings show the significant SNPs with candidate genes for the TNB, NBA and NBH traits in Yorkshire pigs. [ABSTRACT FROM AUTHOR]

Summary: DNA methylation was one of the earliest discovered epigenetic modifications in vertebrates, and is an important epigenetic mechanism involved in the expression of genes in many biological processes, including muscle growth and development. Its effects on economically important traits are evidenced in reported differences in meat quality traits between Chinese indigenous pig breeds (Wannanhua pig) and Western commercial pig breeds (Yorkshire pig), and this presents a unique model for analyzing the effects of DNA methylation on these traits. In the present study, a whole genome DNA methylation analysis was performed on the two breeds using methylated DNA immunoprecipitation. GO functional enrichment and pathway enrichment analyses identified differentially methylated genes primarily associated with fatty acid metabolism, biological processes of muscle development and signaling pathways related to muscle development and pork quality. Differentially methylated genes were verified by sodium pyrosequencing, and the results were consistent with the sequencing results. The results of the integrative analysis between DNA methylation and gene expression revealed that the DNA methylation levels showed a significantly negative correlation with gene expression levels around the transcription start site of genes. In total, 41 genes were both differentially expressed and methylated; these genes were related to fat metabolism, lipid metabolism and skeletal muscle development. This study could help further explore the molecular mechanisms and phenotypic differences in pig growth and development among different breeds. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to evaluate the efficacy and safety of treating lower eyelid fat bulging with ultrasound‐assisted lipolysis (UAL) by performing a preclinical evaluation of the procedure on a Yorkshire pig. Methods: Two white Yorkshire pigs had lower eyelid fat bulging treated with UAL using a probe with a diameter of 1.0 mm or less. Fourteen days after treatment, we evaluated the changes in fat thickness from ultrasound, changes in skin contour (volume and height) from the Antera 3D™, and the disruption of fat cells and changes in collagen synthesis from histological evaluation. Results: Fourteen days after treatment, the fat layer was significantly reduced with no damage to the skin surface. The mean change in the subcutaneous fat layer thickness was decreased 1.51‐0.75 mm in ultrasound analysis. The skin contour of the treated area also decreased with time from 202.5 to 163.5 mm in mean volume and 0.8111 to 0.646 mm in mean height. Masson's trichrome staining showed that the UAL treatment induced the regeneration and remodeling of collagen. Conclusion: The results of this study demonstrate that UAL successfully reduced the bulging lower eyelid fat of a Yorkshire pig and also increased collagen contraction to tighten skin. UAL may be a beneficial and well‐tolerated treatment option for lower eyelid fat bulging. [ABSTRACT FROM AUTHOR]

Litter size in modern so called hyperprolific pig (Sus scrofa Linnaeus) breeds such as of crossbred Danish Landrace x Danish Yorkshire (LY/YL) sows increased remarkably over recent years, however, commonly associated with reduced piglet birth weight and higher within litter birth weight variability likely due to a limited uterine capacity. Since investigation into this issue is patchy, the aim of this study was to investigate uterine capacity based on litter and placental characteristics in two sow lines with different prolificacy, that is crossbred Danish genetic (Danish Landrace x Danish Yorkshire; DG; n = 14) and purebred German Saddleback (GS) sows (n = 12). Parameters recorded were litter size, piglet birth weight and vitality, placental weight and surface area as well as placental vascularization. Litters of DG were on average larger than of GS (p <.001). Piglets of DG weighed on average less than GS (p <.001) and were less vital (p <.001–.142). Increasing litter size was associated with reduced piglet birth weight and increased within litter birth weight variability in GS, but not in DG. DG had on average a lower placental weight (p <.001) and smaller placentae (p <.001) than GS, but the placenta was on average more efficient than of GS (based on the quotient of piglet and corresponding placental weight; p <.001). Vascularization of placentae was on average not or only slightly different between breeds (p <.05 –.982). Remarkably, however, vascularization of the lateral and apical chorionic epithelium of the chorionic ridges as the immediate foetal/maternal interface was on average slightly higher in DG than GS (p <.05–.111). Results thus demonstrate that uterine capacity based on litter and placental characteristics is higher in DG than GS sows. [ABSTRACT FROM AUTHOR]

Summary: A recessive sperm defect of Yorkshire boars was detected more than a decade ago. Affected boars produce ejaculates that contain spermatozoa with defective acrosomes, resulting in low fertility. The acrosome defect was mapped to porcine chromosome 15 but the causal mutation has not been identified. We re‐analyzed microarray‐derived genotypes of affected boars and confirmed that the acrosome defect maps to a 12.24 Mb segment of porcine chromosome 15. To detect the mutation causing defective acrosomes, we sequenced the genomes of two affected and three unaffected boars to an average coverage of 11‐fold. Read depth analysis revealed a 55 kb deletion that is associated with the acrosome defect. The deletion encompasses the BOLL gene encoding the boule homolog, an RNA binding protein which is an evolutionarily conserved member of the DAZ (Deleted in AZoospermia) gene family. Lack of BOLL expression causes spermatogenic arrest and sperm maturation failure in many species. Boars that carry the deletion in the homozygous state produce sperm but their acrosomes are defective, suggesting that lack of porcine BOLL compromises acrosome formation. Our findings warrant further research to investigate the role of BOLL during spermatogenesis and sperm maturation in pigs. [ABSTRACT FROM AUTHOR]

Summary: Pigs are one of the earliest domesticated animals and multiple breeds have been developed to meet the various demands of consumers. EigenGWAS is a novel strategy to identify candidate genes that underlying population genetic differences and to infer candidate regions under selection as well. In this study, EigenGWAS and Fst analyses were performed using the public re‐sequencing data of three typical commercial pig breeds, Duroc, Landrace and Yorkshire. The intersection of genome‐wide significant SNPs detected by EigenGWAS and top‐ranked 1% SNPs of Fst results were treated as signals under selection. Using the data of all three breeds, 3062 signals under selection were detected and the nearby genomic regions within 300 kb upstream and downstream covered 6.54% of whole genome. Pairs of breeds were analysed along with the pathway analysis. The gene function enrichment results indicated that many candidate genes located in the genomic regions of the signals under selection were associated with biological processes related to growth, metabolism, reproduction, sensory perception, etc. Among the candidate genes, the FSHB, AHR, PTHLH, KDR and FST genes were reported to be associated with reproductive performance; the KIT, KITLG, MITF, MC1R and EDNRB genes were previously identified to affect coat colour; the RETREG1, TXNIP, BMP5, PPARD and RBP4 genes were reported to be associated with lipid metabolism and growth traits. The identified genetic differences across the three commercial breeds will advance understanding of the artificial selection history of pigs and the signals under selection will suggest potential uses in pig genomic breeding programmes. [ABSTRACT FROM AUTHOR]

Background and Objective: There are a growing number of porcine models being used for orthopaedic experiments for human beings. Therefore, pain management of those research pigs using ultrasound (US)‐guided nerve block can be usefully performed. The aim of this study is to determine optimal US approaches for accessing and localizing the sciatic nerve at the midthigh level, a relevant block site for hindlimb surgery in female Yorkshire pigs. Methods: As a first step, we dissected the intubated, blood‐washed out pigs (n = 3) and confirmed the anatomical position of the sciatic nerve at midthigh level. After dissection, we found the sciatic nerve, connected with nerve stimulator, and checked the dorsiflexion or plantar flexion of the hindlimb. We matched the sciatic nerve location with the US image. After the pigs were euthanized, the neural structures of the sciatic nerve were confirmed by histological examination with H&E staining. In second step, a main US‐guided sciatic nerve block study was done in the intubated, live pigs (n = 8) based on the above study. Results: In lateral position, the effective US‐guided nerve block site was about 6 cm from the patella crease level; immediately proximal to the bifurcation of the sciatic nerve into the tibial nerve and common peroneal nerve. The distal femur was selected as the landmark. There were no vessels or other nerves surrounding the sciatic nerve. The needle‐tip was positioned less than 1 cm lateral from the distal femur and about 2 cm deep to skin. 'Donut sign' in US images was confirmed in all 16 nerves. Conclusions: Midthigh level sciatic nerve is located superficially, which enables nerve block to be easily performed using US. This is the first study to describe midthigh sciatic nerve block in the lateral position under US guidance in a porcine model from a clinical perspective. [ABSTRACT FROM AUTHOR]

Summary: Despite their important roles in host nutrition and metabolism, and potential to cause disease, our knowledge of the fungal community in the mammalian gut is quite limited. To date, diversity and composition of fungi in swine gut still remains unknown. Therefore, the first internal transcribed spacer of fungi in faecal samples from three breeds of pigs (10 pigs for each breed) was sequenced based on an Illumina HiSeq 2500 platform, and the relationship between the fungal community and the concentrations of main short‐chain fatty acids (SCFAs) was also analysed. Results indicated that Chenghua (local, higher body fat rate), Yorkshire (foreign, higher lean meat and growth rate) and Tibetan (plateau, stronger disease resistance) pigs harboured distinct fungal community. The Basidiomycota and Ascomycota presented as the two predominant phyla, with Loreleia, Russula and Candida as the top three genera in all samples. Network analysis revealed a total of 35 correlations among different fungal genera, with 27 (77.14%) positive and 8 (22.86%) negative pairwise interactions. Canonical correspondence analysis suggested that fungi in the faeces of pigs were more correlated to the concentration of acetate and butyrate rather than propionate. Spearman's correlation further showed that Tomentella was positively correlated to both acetate and butyrate, and Loreleia was positively correlated to propionate (P < 0.05), while Nephroma and Taiwanofungus were negatively correlated to acetate and propionate (P < 0.05). These findings expanded our knowledge on the intestinal fungi in pigs with different genotypes and phenotypes, indicating that fungi may play an indispensable role during the metabolism of host and the maintenance of intestinal health. The cross‐feeding between fungi and other microorganisms may be crucial during the digestion of dietary carbohydrates and the associated physiological processes, which is worthy to be further studied. [ABSTRACT FROM AUTHOR]

Key points: We have developed a novel porcine model of high‐thoracic midline contusion spinal cord injury (SCI) at the T2 spinal level.We describe this model and the ensuing cardiovascular and neurohormonal responses, and demonstrate the model is efficacious for studying clinically relevant cardiovascular dysfunction post‐SCI.We demonstrate that the high‐thoracic SCI model, but not a low‐thoracic SCI model, induces persistent hypotension along with a gradual reduction in plasma noradrenaline and increases in plasma aldosterone and angiotensin II.We additionally conducted a proof‐of‐concept long‐term (12 weeks) survival study in animals with T2 contusion SCI demonstrating the potential utility of this model for not only acute experimentation but also long‐term drug studies prior to translation to the clinic. Cardiovascular disease is a leading cause of morbidity and mortality in the spinal cord injury (SCI) population, especially in those with high‐thoracic or cervical SCI. With this in mind, we aimed to develop a large animal (porcine) model of high‐thoracic (T2 level) contusion SCI and compare the haemodynamic and neurohormonal responses of this injury against a low‐thoracic (T10 level) model. Ten Yorkshire pigs were randomly subjected to 20 cm weight drop contusion SCI at either the T2 or the T10 spinal level. Systolic blood pressure (SBP), mean arterial pressure (MAP) and heart rate (HR) were continuously monitored until 4 h post‐SCI. Plasma noradrenaline (NA), aldosterone and angiotensin II (ANGII) were measured pre‐SCI and at 30, 60, 120 and 240 min post‐SCI. Additionally, two Yucatan pigs were subjected to T2‐SCI and survived up to 12 weeks post‐injury to demonstrate the efficacy of this model for long‐term survival studies. Immediately after T2‐SCI, SBP, MAP and HR increased (P < 0.0001). Between decompression (5 min post‐SCI) and 30 min post‐decompression in T2‐SCI, SBP and MAP were lower than pre‐SCI (P < 0.038). At 3 and 4 h after T2‐SCI, SBP remained lower than pre‐SCI (P = 0.048). After T10‐SCI, haemodynamic indices remained largely unaffected. Plasma NA was lower in T2‐ vs. T10‐SCI post‐SCI, whilst aldosterone and ANGII were higher. Both chronically injured pigs demonstrated a vast reduction in SBP at 12 weeks post‐SCI. Our model of T2‐SCI causes a rapid and sustained alteration in neurohormonal control and cardiovascular function, which does not occur in the T10 model. Key points: We have developed a novel porcine model of high‐thoracic midline contusion spinal cord injury (SCI) at the T2 spinal level.We describe this model and the ensuing cardiovascular and neurohormonal responses, and demonstrate the model is efficacious for studying clinically relevant cardiovascular dysfunction post‐SCI.We demonstrate that the high‐thoracic SCI model, but not a low‐thoracic SCI model, induces persistent hypotension along with a gradual reduction in plasma noradrenaline and increases in plasma aldosterone and angiotensin II.We additionally conducted a proof‐of‐concept long‐term (12 weeks) survival study in animals with T2 contusion SCI demonstrating the potential utility of this model for not only acute experimentation but also long‐term drug studies prior to translation to the clinic. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate group‐ and breed‐specific genetic parameters for reproductive traits in Chinese Duroc, Landrace, and Yorkshire populations. Records for reproductive traits between April 1998 and December 2017 from 92 nucleus pig breeding farms, which were involved in the China Swine Genetic Improvement Program, were analysed. Due to weak genetic connectedness across all farms, connectedness groups consisting of related farms were used. Three, two and four connectedness groups for Duroc, Landrace and Yorkshire were firstly established according to the genetic connectedness rating among farms. For each connectedness group a five‐trait animal model was implemented, and via restricted maximum likelihood procedure the genetic parameters were estimated for five reproductive traits i.e., total number born (TNB), number born alive (NBA), litter weight at farrowing (LWF), farrowing interval (FI) and age at first farrowing (AFF). The average of heritabilities among connectedness groups ranged from.01 (for FI in Yorkshire) to.30 (for AFF in Duroc). Estimates of repeatability for litter traits ranged from.14 to.20 and were consistent for each breed, and for FI, the estimates varied from.01 to.11 across breeds and groups. The estimated genetic correlations among litter traits (i.e., TNB, NBA and LWF) were all significantly high (>.56) and similar across breeds. Averaged genetic correlations over three breeds were −.25, −.27, −.18, −.04, −.10, −.02, and.28 for FI‐TNB, FI‐NBA, FI‐LWF, AFF‐TNB, AFF‐NBA, AFF‐LWF and FI‐AFF, respectively. The standard errors of the estimates were all very low (<0.01) in most situations. Results from this study suggest that selection based on TNB which is currently used in dam line selection index can improve NBA and LWF simultaneously. However, care should be taken on FI and AFF as they are both greatly influenced by non‐genetic factors such as management and measurement. [ABSTRACT FROM AUTHOR]

Objectives: To test the feasibility of a novel method of heart donation under circulatory death criteria that allows precardiectomy donor heart assessment.Materials and Methods: This is a translational study utilizing 16 female Yorkshire pigs in a series of eight heart transplant procedures under a circulatory death model.Results: Successful resuscitation of the donor hearts occurred in seven out of eight animals. All seven of these hearts were deemed to have good function and were successfully transplanted. In the animal in which donor heart resuscitation was not successful, the transplant was aborted, and a left ventricular assist device (LVAD) was placed in the recipient's heart.Conclusion: This animal study demonstrates the feasibility of using this novel technique for resuscitation and precardiectomy evaluation of donated after circulatory death hearts. For those donor hearts without adequate function, an LVAD can be safely implanted as a "bail-out" option. The limitations of this technique are the patient population to which it can be applied (only those patients eligible and consented for LVAD). [ABSTRACT FROM AUTHOR]

Comparison of the multi‐trait animal model and the traditional repeatability model was carried out using data obtained from 6,424 Landrace and 20,835 Yorkshire sows farrowed from January 2000 to April 2018 in order to estimate genetic parameters for litter traits at different parities. Specifically, records of the total number born (TNB), number born alive (NBA), total number of mortality (MORT), number of stillborn (NSB) and number of mummified pigs (MUM) were used. Although results showed the heterogeneity of heritability for litter traits at different parities, the mean heritability estimates from the multi‐trait model were found to be higher than those of the repeatability model for all traits in both pig breeds. In terms of genetic correlation between parities, a slight difference in genetic control in the first parity was noted for TNB and NBA in Landrace and Yorkshire pigs. The correlation between the first parity and later parities ranged from 0.48 to 0.74 for TNB and NBA in both breeds. Moreover, genetic correlation between parities for MORT and NSB was observed to be high for parities higher than 2 in Yorkshire pigs. For MUM, genetic correlation between the first and other parities was generally low in both breeds, indicating that culling pigs on the basis of MUM at the first parity could probably be unreasonable. Overall, the results of this study suggest that the multi‐trait approach for litter size traits is useful for the accurate estimation of genetic parameters. [ABSTRACT FROM AUTHOR]

Summary: LncRNAs comprise a vast majority of the RNAs transcribed from non‐coding regions of mammalian genomes. Recently, lncRNAs have emerged as key regulators of a wide range of biological processes. In this study, we identified lncRNAs expressed in swine ovary tissue from Yorkshire and Meishan pigs. We obtained 3827 lncRNAs expressed from 4973 transcripts in swine ovary tissue, of which 510 were ovary specific, 192 were differentially expressed between Yorkshire and Meishan pigs and 38 were both ovary specific and differentially expressed. Furthermore, we randomly selected several differentially expressed and ovary‐specific lncRNAs for verification by qRT‐PCR and RT‐PCR respectively. We also predicted the functions of the lncRNAs by analysing their nearest neighbouring protein‐coding genes. Together, our results identify a series of ovary‐associated lncRNAs for further experimental investigation of the functions of these genes in ovary development or for selection of candidate genes for breeding. [ABSTRACT FROM AUTHOR]

Summary: In this study, we conducted genomic prediction for two Yorkshire purebred populations (Yichun and Chifeng) from two different provinces of China that both had a limited population size. Two growth traits (age adjusted to 100 kg weight, AGE; back‐fat thickness adjusted to 100 kg weight, BF) and one reproduction trait (total number of piglets born, TNB) were analyzed with four prediction strategies: one‐population BLUP, joint two‐population BLUP, one‐population single‐step BLUP (SSBLUP) and joint two‐population SSBLUP. Our results illustrate that accuracies of genomic estimated breeding values were improved for BF and TNB for the Yichun population and for BF for the Chifeng population by genomic prediction (one‐population SSBLUP and joint two‐population SSBLUP). The accuracy of TNB for the Yichun population was increased two fold when comparing the one‐population SSBLUP to the one‐population BLUP prediction. Meanwhile, prediction biases were dramatically reduced for AGE for the Yichun population and for TNB for the Chifeng population. The conclusions of this study are as follows: first, genomic prediction is useful for improving prediction accuracy for purebred pig breeding farms with a limited population size; second, joint genomic prediction for different populations of the same breed with certain genetic links has the trend to further improve prediction accuracy. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the expression difference of miRNAs and mRNAs between the follicular phase (FP) and luteal phase (LP) in porcine ovaries and provide a theoretical basis for the research on mammalian reproductive regulation. RNA‐Seq and miRNA‐Seq were used to identify differentially expressed genes (DEGs) and miRNAs (DEMs) between the FP and LP in ovaries of six sows (3‐year‐old Yorkshire pigs with similar weights and same parities). Bioinformatic analysis was used to screen potential genes and miRNAs related to porcine ovarian function. Real‐time qualitative PCR was used to validate the sequencing results. RNA‐Seq results showed that 3,078 genes were up‐regulated, and 1,444 genes were down‐regulated in the LP compared with the FP, and DEGs were significantly enriched in 242 Gene Ontology (GO) terms and 33 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. miRNA‐Seq identified 112 DEMs, of which 25 were up‐regulated and 87 were down‐regulated in the LP compared with the FP. We obtained 186 intersection genes (IGs) between the 4,522 DEGs and 2,444 target genes predicted from the 112 DEMs. After constructing a miRNA‐gene‐pathway network, we identified key miRNAs and genes including miR‐17‐3p, miR‐214, miR‐221‐5p, miR‐125b, FGF1, YWHAG, YWHAZ, FDFT1 and DHCR24, which are enriched in Hippo and PI3K‐Akt signalling pathways, and various metabolic pathways. These results indicate that these key genes and miRNAs may play important roles in the developmental transition from FP to LP in porcine ovaries and represent candidate targets for further study. [ABSTRACT FROM AUTHOR]

Tibetan pigs from the Tibetan Plateau are characterized with a significant phenotypic difference relative to lowland pigs. In this study, a significant difference of the fatness and fatty acid composition traits was observed between the Tibetan and Yorkshire pigs. To uncover the involved mechanism, the expression profile of long noncoding RNAs (lncRNAs) and genes was compared between them. After serial filtered steps, 1,964 lncRNAs were obtained through our computational pipeline. In total, 63 and 715 lncRNAs and genes were identified to be differentially expressed. Evidence from cis- and trans-targeting analysis of lncRNAs demonstrated that some lncRNAs, such as MSTRG.14097 and MSTRG.8034, played important roles in the fatness and fatty acid composition traits. Bioinformatics analysis revealed that many candidate genes were responsible for the two traits. Of these, FASN, ACACA, SCD, ME3, PDHB, ACSS1, ACSS2, and ACLY were identified, which functioned in regulating the level of hexadecanoic acid, hexadecenoic acid, octadecenoic acid, and monounsaturated fatty acid. And LPGAT1, PDK4, ACAA1, and ADIPOQ were associated with the content of stearic acid, octadecadienoic acid, and polyunsaturated fatty acid. Candidate genes, which were responsible for fatness trait, consisted of FGF2, PLAG1, ADIPOQ, IRX3, MIF, IL-34, ADAM8, HMOX1, Vav1, and TLR8. In addition, association analysis also revealed that 34 and 57 genes significantly correlated to the fatness and fatty acid composition trait, respectively. Working out the mechanism caused by these lncRNAs and candidate genes is proven to be complicated but is invaluable to our understanding of fatness and fatty acid composition traits. [ABSTRACT FROM AUTHOR]

Background: Hyperoxemia (arterial oxygen tension >100 mm Hg) may occur in critically ill patients and have effects on mixed venous saturation (SvO2 ) and on Fick-based estimates of cardiac output (CO). We investigated the effect of hyperoxemia on SvO2 and on assessments of CO using the Fick equation.Methods: Yorkshire swine (n = 14) were anesthetized, intubated, and paralyzed for instrumentation. SvO2 (co-oximetry) and tissue oxygen tension (tPO2 , implantable electrodes) in brain and myocardium were measured during systematic manipulation of arterial oxygen tension (PaO2 ) using graded hyperoxia (fraction of inspired oxygen 0.21 → 0.8). Secondarily, oxygen- and carbon dioxide-based estimates of CO (FickO2 and FickCO2 , respectively) were compared with measurements from a flow probe placed on the aortic root.Results: Independent of changes in measured oxygen delivery, cerebral and myocardial tPO2 increased in proportion to PaO2 , as did SvO2 (P < 0.001 for all). Based on mixed model analysis, each 100 mm Hg increase in PaO2 resulted in a 4.8 ± 0.9% increase in SvO2 under the conditions tested. Because neither measured oxygen consumption, arterial oxyhemoglobin saturation or cardiac output varied significantly during hyperoxia, changes in SvO2 resulted in successively increasing errors in FickO2 during hyperoxia (34% during normoxia, 72% during FiO2 0.8). FickCO2 lacked the progressively worsening errors present in FickO2 , but correlated poorly with CO.Conclusion: SvO2 acutely changes following changes in PaO2 even absent changes in measured DO2 . This may lead to errors in FickO2 estimates of CI. Further work is necessary to understand the impact of this phenomenon in disease states. [ABSTRACT FROM AUTHOR]

Days to reach 113.4 kg, adjusted backfat depth and adjusted loin muscle area to 113.4 kg were evaluated on pure-bred Landrace (n = 15 660) and Yorkshire (n = 14 808) boars and gilts. Daily lactation feed intake ( LFI) was recorded within parity records from pure-bred Yorkshire (n = 1587) and Landrace (n = 2197) females during day 1-22 of lactation, and LFI curves were predicted using a mixed model. Evaluation of feed intake differences between 2 consecutive days of lactation resulted in the following periods: day 1-6 ( PB1), day 7-10 ( PB2) and day 11-18 ( PB3). Average rate of change in intake ( ARC), average daily intake ( ADI) and variation from predicted daily LFI values ( VAR) metrics were computed for each period of lactation. Gibbs sampling was used to estimate the genetic covariance between LFI metrics and grow-finish traits. Genetic correlations were strongest between grow-finish traits, and LFI metrics in first parity sows and were generally favourable, but correlations with LFI metrics during parity 2 or greater were low and not different from 0 (p > 0.05). Genetic correlations between LFI metrics in parity 1 sows with growth and composition traits varied greatly in strength and direction. Selection for leaner, heavier muscled gilts had a limited effect on LFI metrics. However, selection for increased growth rate was associated with higher ARC and ADI and smaller VAR values. [ABSTRACT FROM AUTHOR]

Genome-wide association study identifies variants associated with AFS and GL in Danish Yorkshire pig population The productivity per sow per year (PSY) has key impact on the economic benefits in swine industry.1 Age at first service (AFS) and gestation length (GL) are the two important components of PSY.2,3 Previous QTL studies and GWASs have identified the genomic regions and SNPs that are associated with AFS and GL in different pig breed populations, but have not been reported in the Danish population. [Extracted from the article]