3D Bioprinting of Pig Macrophages and Human Cells Discovered the P2Y14 Receptor as a Mediator of Xenogenic Immune Responses.

BACKGROUND: The survival rate of pig lung xenotransplantation (PLXTx) recipients is severely limited by intense xenogenic immune responses, necessitating further insights into xenogeneic immunity and the development of models to study the PLXTx immune response. METHODS: We identified regulators of PLXTx immune response Using Gene ontology analysis. We assessed the metabolic changes and protein levels in 3D4/31 pig alveolar macrophages (PAMs) through flow cytometry and immunoblotting. To induce a xenogenic immune response, we co-cultured 3D4/31-PAMs with A549 human alveolar epithelial cells and evaluated cytokine expression using qRT-PCR. RESULTS: Gene ontology analysis identified STAT1 and alveolar macrophages as contributors to lung autoimmunity and transplant rejection. In 3D4/31-PAMs, phorbol myristate acetate-induced glycogen accumulation and cyclooxygenase-2 expression were inhibited by the P2Y14 inhibitor PPTN. Co-culturing 3D4/31-PAMs with A549 human alveolar epithelial cells via 3D bioprinting resulted in a more pronounced inflammatory response than 2D co-culture, with increased expression of genes related to the P2Y14 cascade and inflammation. This inflammatory gene expression was prevented by PPTN treatment. CONCLUSION: Based on these results, we propose alginate bioprinting as an in vitro model for PLXTx and suggest that P2Y14 is a key regulator of xenogeneic immune responses in PAMs.

The role of reproductive tract extracellular vesicles on boar sperm function.

Extracellular vesicles (EVs) are abundant in reproductive tract fluids and serve as important mediators of paracrine communication, influencing the function of gametes. Sperm undergo development in the male reproductive tract and exert their function within the female reproductive tract, engaging in interactions with various types of EVs present throughout the reproductive system. Previous studies have demonstrated that both male and female reproductive tract EVs can impact sperm function by transferring regulatory cargoes to them. Nevertheless, inconsistencies of previous research regarding the effects of EVs on sperm function, coupled with a lack of investigation into the influence of female reproductive tract EVs on sperm fertilization, have left the true role and underlying mechanisms of reproductive tract EVs on sperm function largely unexplored. Given that pigs represent significant economic livestock and serve as an ideal biomedical model for human diseases, this review aims to provide a comprehensive summary of the current knowledge regarding reproductive tract EVs and their influence on boar sperm function, while highlighting their potential roles. We anticipate that this review will facilitate future research on reproductive tract EVs and their impact on sperm function, contributing to improved animal reproductive efficiency and advancements in the treatment of male infertility.

Predicting primal weight and primal yield in pork carcasses from a large-scale survey at major meat processing centers in Japan.

Pork primal weight and primal yield are important indicators for pig breeding, feeding management, commercial distribution systems, and meat processing. Here, we aimed to determine whether primal weight and primal yield could be predicted through non-destructive measurements of pork carcass traits. A total of 4397 carcasses (1958 gilts and 2439 barrows) from eight major meat processing centers were used, and the mean primal weight and primal yield were 56.0 kg and 73.9%, respectively. Significant sex differences were observed for all primal and carcass traits (P < 0.001), except for carcass weight. A maximum of 12 variables were examined, and primal weight was predicted with very high accuracy (R = 0.95, RMSE = 1.7, RPD = 3.0) using four variables. Primal yield was predicted with relatively good accuracy (R = 0.71, RMSE = 2.3, RPD = 1.4) using three variables, and these same variables were also effective for predicting primal weight. These prediction formulas were sufficiently accurate without accounting for the effect of sex. Overall, our results demonstrate that primal weight and primal yield can be accurately predicted using four variables, "carcass weight," "backfat thickness above M. gluteus medius," "spinous process length of 13th thoracic vertebra," and "length from 1st thoracic vertebra to backfat," without accounting for the effect of sex.

Organic waste recycling application increases N availability and mitigates N2O emission without crop yield penalty in the North China Plain.

Introduction: Agricultural organic waste recycling can supply nutrients for crop production and partially replace chemical nitrogen fertilizers, which is beneficial for waste management and environmental protection. Nevertheless, comprehensive evaluation of the effects of different organic materials applications on crop yield and the environment is limited. Methods: Therefore, in this study, a comprehensive investigation of the synergistic effects of straw, pig manure, and biogas residue recycling on the wheat (Triticum aestivum L.) and maize (Zea mays L.) systems was carried out in the North China Plain. Field experiments were conducted from 2019 to 2021, comprising five treatments: straw (ST), pig manure (PM), and biogas residue (BR) partially replacing chemical nitrogen fertilizer, sole application of chemical nitrogen fertilizer (CF), and a control with no nitrogen application (WN). Results and discussion: The results showed that organic materials significantly increased soil total nitrogen (3.04%-9.10%) and N recovery efficiency (REN; 42.21%-44.99%), but pig manure was more beneficial in increasing crop yields (3.50%), especially wheat yields (8.72%), and REN was significantly higher than that of the other treatments. Organic materials performed differently in wheat and maize seasons, and wheat yield could be improved by organic materials return. Organic materials stimulated N2O emission in wheat season (4.28%-32.20%), while biogas residue inhibited the N2O emission in maize season (47.47%). The negative effect of straw and biogas residue on yield decreased with increasing years of return, and pig manure continued to contribute to yield. In conclusion, pig manure is the optimal alternative that can increase crop yield, soil N content, and REN without stimulating N2O emissions.

Rearing pigs with play opportunities: the effects on disease resilience in pigs experimentally inoculated with PRRSV.

Positive emotions can reduce disease susceptibility during infectious challenges in humans, and emerging evidence suggests similar effects in farm animals. Because play behaviour may support a positive emotional state in pigs, this study investigates whether rearing pigs with regular intermittent play opportunities enhances disease resilience when challenged with porcine reproductive and respiratory syndrome virus (PRRSV). Litters were assigned to either play (PLY; n = 5 L) or control (CON; n = 4 L) treatments at birth. In PLY, play was promoted with extra space and enrichment items for three hours daily from five days of age (doa). At weaning (25 ± 2 doa; mean ± SD), 28 pigs (14/treatment) were selected for a disease challenge, based on weight, sex, and sow. The pigs were transported to a disease containment facility and at 43 ± 2 doa (day 0 post-inoculation, DPI) inoculated with PRRSV. Skin lesions, blood, rectal temperature, clinical signs, body weight, and behaviour were collected pre- and post-inoculation. Play opportunities for PLY continued every other day until euthanasia of all pigs at 65 ± 2 doa (22 DPI). PLY pigs exhibited fewer skin lesions following transport and throughout the infection compared to CON. Although the viral load did not differ between treatments, PLY pigs had a lower probability of experiencing moderate and severe respiratory distress, with a shorter duration. PLY also performed better throughout the infection, showing higher ADG and greater feed efficiency. The immune response differed as well. PLY pigs had fewer monocytes on 8 DPI than CON, with levels returning to baseline by 21 DPI, whereas CON levels exceeded baseline. Regardless of day of infection, lymphocyte counts tended to be lower in PLY than in CON, and white blood cells and neutrophils were also lower, but only in slow-growing pigs. PLY pigs continued to play during the infection, demonstrating less sickness behaviour and emphasizing the rewarding properties of play. Results suggest that PLY pigs were less affected by PRRSV and developed increased resilience to PRRSV compared to CON. This study demonstrates that rearing pigs in an environment supporting positive experiences through provision of play opportunities can enhance resilience against common modern production challenges, underscoring the value of positive welfare in intensive pig farming.

A sensitive immunoassay for the quantitation of Pig-MAP in pig saliva samples.

The purpose of the study is to develop a sensitive assay for the proper quantification of the acute phase protein Pig-MAP in pig saliva samples. A time-resolved immunofluorometric assay (TR-IFMA) was developed using two pig-MAP-specific monoclonal antibodies. The limit of detection of the assay was 4 ng/mL, enough to measure pig-MAP concentration in saliva. Precision was evaluated for saliva samples of low, medium and high concentration, with inter assay CV of 4-14 % and inter-assay CV of 8-20 %. The assay kept linearity under dilution and a method comparison study performed with serum samples showed good correlation with ELISA. Median Pig-MAP concentration in saliva from healthy animals was 19 ng/mL whereas in pigs with different inflammatory conditions was 11 times higher. In the same animals median pig-MAP serum concentrations were 0.72 mg/mL in the healthy group and 4.61 in the diseased group. The Spearman coefficient of correlation between Pig-MAP concentration in serum and saliva was of 0.72. A correlation was also observed between the salivary concentration of pig-MAP and other two acute phase proteins such as haptoglobin (r = 0.62) or C-reactive protein (r = 0.65). The concentration of Pig-MAP in saliva of pigs with severe respiratory disease decreased significantly from a median value of 128 ng/mL at the time of disease detection to 8 ng/mL after 1 day of antibiotic therapy. Studies performed show that pig-MAP is present in saliva and this specimen may be an alternative to serum for pig-MAP quantification.

A pig model exploring the postnatal hair follicle cycle.

Introduction: The hair follicle (HF) is a micro-organ capable of regeneration. A HF cycle consists of an anagen, catagen and telogen. Abnormalities in the HF cycle can lead to many hair disorders such as hair loss. The pig is a good biomedical model, but there are few data on their HF cycle. The aim of this study was to classify the pig HF cycle and determine the feasibility of the pig as an animal model for human HF cycle. Methods: Skin samples from 10 different postnatal (P) days Yorkshire pigs was collected to determine the key time points of the first HF cycle in pig by H&E staining, immunofluorescence staining, q-PCR and western-blot. Results: By morphological observation and detection of markers at different stages, pig HF cycle was classified into three main periods - the first anagen until P45, catagen (P45-P85), telogen (P85-P100), and next anagen (>P100). In addition, we examined the expression of important genes AE15, CD34, Versican, Ki67 et al. related to the HF cycle at different stages of pig HF, indicating that pig and human share similarities in morphology and marker gene expression patterns of HF cycle. Discussion: Our findings will facilitate the study of HF cycle and offer researchers a suitable model for human hair research.

Melatonin decreases excessive polyspermy for single oocyte in pigs through the MT2 receptor.

Melatonin supplementation during in vitro maturation (IVM) improves porcine oocyte maturation and embryonic development by exerting antioxidative effects. Nevertheless, the mechanism by which melatonin prevents polyspermy after in vitro fertilization (IVF) remains unclear. Here, we examined the effects of melatonin on cytoplasmic maturation and the incidence of polyspermic penetration in porcine oocytes. No statistically significant difference was observed in the rate of first polar body formation between the groups (Control, Melatonin, Melatonin + Luzindole, and Melatonin + 4-P-PDOT). Interestingly, melatonin supplementation significantly improved the cytoplasmic maturation of porcine oocytes by enhancing the normal distribution of organelles (Golgi apparatus, endoplasmic reticulum and mitochondria) and upregulating organelle-related gene expressions (P < 0.05). However, these promotional effects were counteracted by melatonin antagonists, suggesting that melatonin enhances cytoplasmic maturation through its receptors in porcine oocytes. Melatonin supplementation also significantly improved the rate of diploid and blastocyst formation after IVF by promoting the normal distribution of cortical granules (P < 0.05). In conclusion, melatonin supplementation during in vitro maturation of porcine oocyte improves fertilization efficiency and embryonic developmental competence by enhancing cytoplasmic maturation.

When the neighbors are noisy: effect of social challenge in collateral pens of stressed animals.

Regrouping practices are frequent in pig production, altering hierarchy and triggering aggressive behaviors. The present study aimed to investigate the physiological responses of piglets to an experimental model designed to induce stress through systematic social mixing in two trials. In Trial A, a total of 144 crossbred piglets (25 days postweaning) housed in one room within 36 pens (four piglets/pen) were used and randomly assigned to either a control group (piglets maintained in their pen, Ctrl-A) or a social challenge group (piglets mixed, SC-A). In Trial B, the same number of animals (33 days postweaning) and crossbreed line was used, and each piglet was assigned either to a control group (Ctrl-B) or a social challenge group (SC-B) in two independent rooms (rooms Ctrl and SC, 12 pens/ room, six piglets/pen). The social challenge consisted of daily moves of three out of four pen mates and five out of six pen mates, for Trials A and B, respectively. In the Ctrl groups, all piglets stayed in their original pen. Before the 1st mixing day and at the end of the 3rd mixing day, saliva (cortisol concentration) and blood (cortisol concentration changes, hemogram, and immunologic activation) samples were collected from two random piglets per pen. Skin lesion scores of all piglets were also recorded on the front, middle, and rear body regions. In Trial A, the total skin lesions score was higher in the SC-A group compared to the Ctrl-A group after the social challenge (0.53 vs. 0.17; p < 0.05), but an unexpected increase between sampling days in the Ctrl-A piglets (0.06 vs. 0.17; p < 0.05) was also recorded, suggesting that Ctrl-A pigs showed similar aggressivity levels to the SC-A group. Hematological parameters hemoglobin, red blood cell counts, and leukocyte counts present similar changes in both treatment groups after the social challenge. Contrarily, in Trial B, the lesion score only increased in the piglets in room SC (0.08 vs. 0.34; p < 0.05). Results suggest that stable groups may show aggressive behaviors if they are in the same room with socially challenged pigs. Thus, the physical separation of treatment groups in social stress studies is recommended.

How do pig veterinarians view technology-assisted data utilisation for pig health and welfare management? A qualitative study in Spain, the Netherlands, and Ireland.

BACKGROUND: Application of data-driven strategies may support veterinarians' decision-making, benefitting pig disease prevention and control. However, little is known about veterinarians' need for data utilisation to support their decision-making process. The current study used qualitative methods, specifically focus group discussions, to explore veterinarians' views on data utilisation and their need for data tools in relation to pig health and welfare management in Spain, the Netherlands, and Ireland. RESULTS: Generally, veterinarians pointed out the potential benefits of using technology for pig health and welfare management, but data is not yet structurally available to support their decision-making. Veterinarians pointed out the challenge of collecting, recording, and accessing data in a consistent and timely manner. Besides, the reliability, standardisation, and the context of data were identified as important factors affecting the efficiency and effectiveness of data utilisation by veterinarians. A user-friendly, adaptable, and integrated data tool was regarded as potentially helpful for veterinarians' daily work and supporting their decision-making. Specifically, veterinarians, particularly independent veterinary practitioners, noted a need for easy access to pig information. Veterinarians such as those working for integrated companies, corporate veterinarians, and independent veterinary practitioners expressed their need for data tools that provide useful information to monitor pig health and welfare in real-time, to visualise the prevalence of endemic disease based on a shared report between farmers, veterinarians, and other professional parties, to support decision-making, and to receive early warnings for disease prevention and control. CONCLUSIONS: It is concluded that the management of pig health and welfare may benefit from data utilisation if the quality of data can be assured, the data tools can meet veterinarians' needs for decision-making, and the collaboration of sharing data and using data between farmers, veterinarians, and other professional parties can be enhanced. Nevertheless, several notable technical and institutional barriers still exist, which need to be overcome.

Changes in choroidal thickness and blood flow in response to form deprivation-induced myopia and repeated low-level red-light therapy in Guinea pigs.

PURPOSE: To evaluate ocular refractive development, choroidal thickness (ChT) and changes in choroidal blood flow in form-deprived myopia (FDM) Guinea pigs treated with repeated low-level red-light (RLRL) therapy. METHODS: Twenty-eight 3-week-old male tricolour Guinea pigs were randomised into three groups: normal controls (NC, n = 10), form-deprived (FD, n = 10) and red light treated with form-deprivation (RLFD, n = 8). Interocular refraction and axial length (AL) changes were monitored. Optical coherence tomography angiography (OCTA) measured choroidal thickness, vessel area density, vessel skeleton density and blood flow signal intensity (flux) in the choriocapillaris and medium-large vessel layers. The experimental intervention lasted 3 weeks. RESULTS: At week 3, the FD group had higher myopia and longer axial length than the NC group (all p < 0.001). The RLFD group had higher hyperopia and shorter axial length than the FD group (all p < 0.001). At week 1, the NC group had a thicker choroidal thickness than the FD group (p < 0.05). At weeks 2 and 3, the RLFD group had a thicker choroidal thickness than the FD group (p = 0.002, p < 0.001, respectively). Additionally, the NC group had higher vessel area density, vessel skeleton density and flux in the choriocapillaris layer than the FD group at the three follow-up time points (all p < 0.05). At week 3, the vessel skeleton density and flux were higher in the RLFD group than in the FD group (all p < 0.05). Correlation analysis results showed that weekly changes in refraction and choroidal thickness were negatively correlated with changes in axial length (all p < 0.05). Choroidal thickness changes were positively correlated with alterations in the vessel area density, vessel skeleton density and flux in the choriocapillaris layer, as well as vessel skeleton density and flux changes in the medium-large vessel layers (all p < 0.05). CONCLUSIONS: Repeated low-level red-light (RLRL) therapy retards FDM progression in Guinea pigs, potentially through increased choroidal blood flow in the choriocapillaris layer.

Effects of straws on greenhouse gas emissions in the ectopic fermentation system.

Straws are commonly used padding materials in the ectopic fermentation system, but their effects on greenhouse gas emissions are not well understood. This study compared the effects of rape, rice and corn straws on the fermentation performance of the ectopic fermentation system. Compared with corn straw, the treatment groups with rape straw and rice straw significantly increased the alpha diversity of the fermentation system, and simultaneously mitigated the cumulative emissions of CO2 and N2O by up to 32.4% and 93.9%, respectively. The CO2 and N2O peak emission in the treatment group with corn straw reached 1.4 × 106 and 36.2 mg/m2/d, respectively. CH4 peak emission was one order of magnitude lower than that of N2O in the ectopic fermentation system. Redundancy analysis showed that Pseudoxanthomonas sp000510725 was the key specie that positively affect the fermentation temperature, CO2 and N2O emissions in the fermentation system. Nitrogen metabolism genes, such as nosZ, nirK, and nirS were more abundant in the surface layer of the fermentation system, indicating more active nitrogen metabolism in this region, and the core zone could be the primary source of N2O emissions. Those findings indicated that rape and rice straw can be potential padding materials for mitigating greenhouse gas emissions in large-scale ectopic fermentation system.

Metabolic profile and glycemic response in fully-grown sows born using assisted reproductive technologies.

The aim of the present work was to gain insight into the metabolism of pigs derived from assisted reproductive technologies during their adulthood. Approximately 4h after feeding, a blood sample was taken from 3.5 year old sows born by artificial insemination (AI group, n = 7) and transfer of in vitro produced embryos (IVP group, n = 11) to determine the physiological concentrations of the main biomarkers of carbohydrates (glucose and lactate), proteins (albumin, creatinine and urea) and lipids (cholesterol and triglycerides). Four weeks later, an oral glucose tolerance test (OGTT; 1.75g glucose/kg body weight) was performed after an overnight fast and 1h of water withdrawal. Blood samples were obtained prior (T = 0 min; fasting conditions) and 15, 30, 45, 60, 90, 120, 150, 180, 210 and 240 min after glucose intake. At each time point, glycemia was measured immediately using glucometer test strips, and serum was collected to determine the above metabolites along with insulin and glucagon. After OGTT, the area under the curve (AUC) between sampling times and homeostasis model assessment of insulin resistance (HOMA) indices were calculated. Under physiological conditions, the concentration of metabolites studied was similar between AI and IVP sows. In both groups, fasting decreased cholesterol and increased triglycerides and urea (P < 0.001). However, creatinine and lactate were similar in both groups under physiological and fasting conditions. The expected increase in albuminemia and decrease in glycaemia after fasting was only observed in IVP sows. OGTT revealed a different glucose curve pattern (monophasic in AI and biphasic in IVP group), a lower mean concentration of cholesterol, glucose, lactate, triglycerides in IVP compared to AI pigs (P < 0.01), and a higher mean concentration of albumin, creatinine and insulin in IVP compared to AI group (P < 0.05). On the contrary, no differences were found between groups for mean serum glucagon and urea levels, nor for glucose homeostasis indices HOMA-IR and HOMA-%B. The AUC differed between groups at several time points with larger AUC for creatinine, and smaller AUC for glucose, glucagon, and triglycerides, in IVP pigs than in AI pigs at 180-210 min (P < 0.05). In conclusion, under physiological conditions the metabolic profile of fully-grown AI and IVP sows is similar and within normal ranges. Glucose challenge revealed differences in metabolic and insulin responses between groups but with normal glucose tolerance in both cases.

Skeletal muscle-derived exosomes selectively coated miRNAs and participate in myoblast proliferation and differentiation mediated by miR-4331-3p.

The phenotypic characteristics and meat quality of skeletal muscles are collectively determined by muscle cells and their intricate interactions with the extracellular microenvironment. In this study, we evaluated muscle fiber phenotypes in the longissimus dorsi (HC-L) and psoas major (HC-P) of Hechuan black pigs. The results revealed significant differences in muscle fiber diameter, density, and type (P < 0.05). Subsequently, co-culture experiments with myoblasts demonstrated that skeletal muscle-derived exosomes (SKM-Exos) promoted myoblast proliferation and differentiation with P-Exo exhibiting superior efficacy in promoting the augmentation of MyHCIIa fiber. Furthermore, SKM-Exos are inherently heterogeneous, and the micro RNAs (miRNAs) present in SKM-Exos are selectively coated. Notably, the expression of miR-4331-3p was significantly higher in SKM-Exos than in the corresponding skeletal muscles. The expression of miR-4331-3p was significantly elevated in the SKM-Exos of HC-L compared to that of HC-P, and it interacted with differentially expressed genes between HC-L and HC-P. Moreover, miR-4331-3p enhanced myoblast proliferation and inhibited differentiation. Our findings offer valuable insights into the molecular processes that contribute to meat formation, including intricate cellular interactions.

Characterization of decellularized porcine oviduct- and uterine-derived scaffolds evaluated by spermatozoa-based biocompatibility and biotoxicity.

Decellularized extracellular matrix (dECM) are widely utilized in regenerative medicine and tissue engineering due to their ability to promote cell growth, proliferation, and differentiation. In reproduction, research is focused on the utilization of these scaffolds to treat pathologies causing reproductive dysfunction or to improve assisted reproduction technologies (ARTs). We developed an efficient protocol employing the immersion-agitation technique to decellularize porcine oviductal and uterine sections, comparing the efficacy of fresh versus frozen treatments. Both methods successfully generated acellular matrices with less than 3 % residual DNA, effectively preserving structural and protein integrity. Scanning and transmission electron microscopy confirmed the ultrastructural integrity, whereas Masson's Trichrome staining highlighted better collagen preservation in frozen treatments. Proteomic analysis of decellularized scaffolds revealed collagen and key macromolecules such as laminin, filamin, dermatopontin, and fibronectin, which are essential for extracellular matrix structure and cell functions such as adhesion and migration. Innovatively, we assessed the biocompatibility and cytotoxicity of the scaffolds using spermatozoa, demonstrating that thorough washing ensures the scaffold biocompatibility without compromising sperm viability or motility. Our findings not only contribute to the standardization of decellularization protocols for female reproductive organs but also emphasize the importance of evaluating sperm biocompatibility to ensure the safety of dECM scaffolds.

Lactation affects postweaning metabolic profiles, but not follicle size in multiparous sows.

Young sows mobilise body reserves to support milk production during lactation, resulting in a negative energy balance (NEB). This NEB affects the development of follicles and oocytes that give rise to the next litter. Decreased IGF1 levels due to a NEB are thought to play a role in this process. As this has hardly been studied in multiparous sows, the current study focused on relations between lactation BW loss (%), metabolic hormones, and follicle development in multiparous sows at Day 0 and Day 4 after weaning. A total of 31 sows of parity 4.7 ± 2.5 were killed at either Day 0 or Day 4 after weaning. Average BW loss during lactation was 3.3 ± 4.5%, while average backfat loss was 4.1 ± 0.3 mm. The metabolic profile confirmed the metabolic impact of lactation as both non-esterified fatty acid (NEFA), and creatinine levels were higher at Day 0 than that at Day 4. Conversely, serum levels of IGF1 and growth differentiation factor 15 levels were lower on Day 0 than on Day 4. A higher BW loss (%) was related to higher NEFA levels on Day 0, but not on Day 4. IGF1 concentrations in serum and follicle fluid were similar at Day 0 and Day 4 and were not related to follicle size on these days. In conclusion, although lactation affected postweaning metabolic profiles in these multiparous sows, follicle size was not related to these profiles, probably due to the relatively mild BW loss of these sows. IGF1 concentrations were less affected by lactation and did not seem to limit follicle development, as it does in sows experiencing high weight loss.

Evaluating social network metrics as indicators of tail injury caused by tail biting in growing-finishing pigs (Sus scrofa domesticus).

Tail biting is a multifactorial behavior that causes welfare and economic challenges in swine production. As of 2024, research exploring the influence of pig social structure on the development of tail biting is limited. The objective of this study was to explore whether social structures of pigs from different litter origins can impact tail biting and, ultimately, tail damage. Pigs (n = 96) were grouped (eight pigs/pen) based on their litter origin: non-littermates (NLM), half-littermates, and littermates (LM). Tail injury scores were assessed twice weekly from 10 to 24 weeks of age, with a maximal tail injury score (MTS) over the study period being used to evaluate victimization by tail biting. Pig behavior was video-recorded at 15, 19, and 23 weeks of age. Association networks based on lying behavior and tail biting interaction networks were evaluated at pen-and pig-levels using social network analysis. Pigs in LM pens experienced higher median MTS compared to pigs in NLM pens (Median = 1.5; Interquartile range = 1-2; p = 0.009). Within association networks, NLM pens had lower degree centralization measures than other pens at both 15 (Estimated marginal mean [EMM] = 0.07; 95% CI = 0.02-0.12; p = 0.003) and 23 weeks (EMM = 0.09; 95% CI = 0.04-0.14; p = 0.01) and pigs in NLM pens had higher weighted degree centrality than those in other pens (EMM = 1.00; 95% CI = 0.90-1.11; p = 0.002), suggesting pigs in NLM pens had more uniform, stronger, and more connections with their pen-mates. In tail biting networks, increased weighted in-degree centrality was associated with increased odds of pigs receiving a more severe MTS (OR = 1.56; 95% CI = 1.08-2.27; p = 0.02). Pigs with increased weighted out-degree centrality tended to have increased odds of receiving a more severe MTS (OR = 1.19; 95% CI = 0.97-1.48; p = 0.09). These preliminary data suggest a potential relationship between social structures and tail biting in growing-finishing pigs.

Effects of phytogenic feed additives in growing and finishing pigs under different stocking density.

This study was to investigate effects of different phytogenic feed additives (PFA) in grower finishing pigs with stressed by high stocking density. A total of 84 growing pigs ([Landrace × Yorkshire] × Duroc) with initial body weight (BW) of 28.23 ± 0.21 kg were used for 10 weeks (4 replicate pens with 3 pigs per pen). The dietary treatment consisted of basal diets in animal welfare density (positive control [PC]), basal diet in high stocking density (negative control [NC]), NC + 0.04% bitter citrus extract (PT1), NC + 0.01% microencapsulated blend of thymol & carvacrol (PT2), NC + 0.10% mixture of 40% bitter citrus extract and 10% microencapsulated blend of thymol and carvacrol (PT3), NC + 0.04% premixture of grape seed and grape marc extract, green tea and hops (PT4), and NC + 0.10% fenugreek seed powder (PT5). The reduction of space allowance significantly decreased (p < 0.05) growth performance (average daily gain, average daily feed intake, feed efficiency) and nutrient digestibility (dry matter, crude protein). Also, the fecal score of NC group increased (p < 0.05) compared with other groups. In blood profiles, lymphocyte decreased (p < 0.05), and neutrophil, cortisol, TNF-α increased (p < 0.05) when pigs were in high stocking density. Basic behaviors (feed intake, standing, lying) were inactive (p < 0.05) and singularity behavior (biting) were increased (p < 0.05) under high stocking density. However, PFA groups alleviated the negative effects such as reducing growth performance, nutrient digestibility, increasing stress indicators in blood and animal behavior. In conclusion, PFA groups improved the health of pigs with stressed by high stocking density and PT3 is the most effective.

Exploring the multifaceted factors affecting pork meat quality.

The significance of pork meat quality extends far beyond mere consumer satisfaction, encompassing crucial aspects such as health and nutrition, economic impact, reputation and branding, food safety, and sustainability within the global food system. Influenced by a multitude of factors, each playing a pivotal role in shaping its sensory attributes and consumer appeal, pork meat quality stands as a cornerstone of the meat industry. Thus, understanding these factors are imperative for ensuring consistent high-quality pork production, aligning with consumer preferences, and elevating overall satisfaction levels. In this review, we provide a comprehensive overview of the diverse factors affecting pork meat quality, including genetic characteristics, rearing systems, feed composition, gender differences, pre-slaughter handling, and meat aging processes.

Progress in Orthotopic Pig Heart Transplantation in Nonhuman Primates.

Xenotransplantation of porcine hearts has become a promising alternative to human allotransplantation, where organ demand still greatly surpasses organ availability. Before entering the clinic, however, feasibility of cardiac xenotransplantation needs to be proven, ideally in the life supporting orthotopic pig-to-nonhuman primate xenotransplantation model. In this review, we shortly outline the last three decades of research and then discuss in detail its most recent advances. These include the genetic modifications of donor pigs to overcome hyperacute rejection and coagulation dysregulation, new organ preservation methods to prevent perioperative xenograft dysfunction, experimental immunosuppressive and immunomodulatory therapies to inhibit the adaptive immune system and systemic inflammation in the recipient, growth control concepts to avoid detrimental overgrowth of the porcine hearts in nonhuman primates, and lastly, the avoidance of porcine cytomegalovirus infections in donor pigs. With these strategies, consistent survival of 6-9 months was achieved in the orthotopic xenotransplantation model, thereby fulfilling the prerequisites for the initiation of a clinical trial.