Developmental biology of Spiralicellula and the Ediacaran origin of crown metazoans.

The early Ediacaran Weng'an biota (Doushantuo Formation, South China) provides a rare window onto the period of Earth history in which molecular timescales have inferred the initial phase of crown-metazoan diversification. Interpretation of the embryo-like fossils that dominate the biota remains contentious because they are morphologically simple and so difficult to constrain phylogenetically. Spiralicellula from the Weng'an biota is distinguished by spiral internal bodies, allied through development to Megasphaera or Helicoforamina and interpreted variously as metazoan embryos, encysting protists, or chlorophycean green algae. Here we show, using X-ray microtomography, that Spiralicellula has a single-layered outer envelope and no more than 32 internal cells, often preserving a nucleus and yolk granules. There is no correlation between the extent of spiral development and the number of component cells; rather, the spiral developed with each palintomic stage, associated with cell disaggregation and reorientation. Evidence for envelope thinning and cell loss was observed in all developmental stages, reflecting non-deterministic shedding of gametes or amoebae. The developmental biology of Spiralicellula is similar to Megasphaera and Helicoforamina, which otherwise exhibit more rounds of palintomy. We reject a crown-metazoan affinity for Spiralicellula and all other components of the Weng'an biota, diminishing the probability of crown-metazoan diversification before the early Ediacaran.

Nutrigenetic and Epigenetic Mechanisms of Maternal Nutrition-Induced Glucolipid Metabolism Changes in the Offspring.

Maternal nutrition during pregnancy regulates the offspring's metabolic homeostasis, including insulin sensitivity and the metabolism of glucose and lipids. The fetus undergoes a crucial period of plasticity in the uterus; metabolic changes in the fetus during pregnancy caused by maternal nutrition not only influence fetal growth and development but also have a long-term or even life-long impact for the offspring. Epigenetic modifications, such as DNA methylation, histone modification, and non-coding RNAs, play important roles in intergenerational and transgenerational effects. In this context, this narrative review comprehensively summarizes and analyzes the molecular mechanisms underlying how maternal nutrition, including a high-fat diet, polyunsaturated fatty acid diet, methyl donor nutrient supplementation, feed restriction, and protein restriction during pregnancy, impacts the genes involved in glucolipid metabolism in the liver, adipose tissue, hypothalamus, muscle, and oocytes of the offspring in terms of the epigenetic modifications. This will provide a foundation for the further exploration of nutrigenetic and epigenetic mechanisms for integrative mother-child nutrition and promotion of the offspring's health through the regulation of maternal nutrition during pregnancy. Note: This paper is part of the Nutrition Reviews Special Collection on Precision Nutrition.

Mechanism of Apoptosis in Porcine Ovarian Granulosa Cells Triggered by T-2 Toxin.

T-2 toxin (T-2), an A-type mono mycotoxin produced by various Fusarium species, disrupts DNA/RNA and protein synthesis upon entering the body, resulting in pathological conditions in various tissues/organs and posing a significant threat to human and animal health. However, the mechanisms underlying its toxicity remain unclear. With the goal of learning how T-2 affects reproduction in animals, we utilized primary porcine ovarian granulosa cells (pGCs) as a carrier in vitro and constructed concentration models for analyzing cell morphology and RNA-sequencing (RNA-seq). Our findings showed that T-2 could influence pGCs morphology, induce cell cycle arrest, and promote apoptosis in a dose-dependent manner. The results of RNA-seq analyses indicated that a total of 8216 genes exhibited significant differential expression (DEG) following T-2 treatment, of which 4812 were observed to be down-regulated and 3404 were up-regulated. The DEGs following T-2 toxin treatment of pGCs had a notable impact on many metabolic pathways such as PI3K-Akt, Ras, MAPK, and apoptosis, which in turn altered important physiological processes. Gene set enrichment analysis (GSEA) indicated that the differences in the harmful effects of T-2 might be caused by the varying control of cellular processes and the pathway responsible for steroid metabolism. These results present further insights regarding the mechanism of T-2 action on sow reproductive toxicity, enhance our understanding of T-2 reproductive toxicological effects, and lay a theoretical foundation for the judicious prevention of T-2-induced reproductive toxicity.

Identification of Breed-Specific SNPs of Danish Large White Pig in Comparison with Four Chinese Local Pig Breed Genomes.

Genetic variation facilitates the evolution, environmental adaptability, and biodiversity of organisms. Danish Large White (LW) pigs have more desirable phenotypes compared with local Chinese pigs, which have difficulty adapting to the modern swine industry. However, the genome-wide mutational differences between these pig breeds are yet to be evaluated. Therefore, this study aimed to evaluate genomic variation and identify breed-specific SNPs in Danish LW pigs. Here, 43 LW, 15 Diqing Tibetan (DQZ), and 15 Diannan small-ear (DN) pigs whose genomes were re-sequenced with 5× depth were selected. This was followed by a conjoined analysis of our previous resequencing data of 24 Anqing six-end white (AQ) and six Asian wild (SS) pigs. In total, 39,158,378 SNPs and 13,143,989 insertion-deletions were obtained in all breeds. The variation number of LW pigs was the lowest, with 287,194 breed-specific and 1289 non-synonymous SNPs compared with Chinese breeds. Functional analysis of the breed-specific non-synonymous SNPs indicated that these mutations were mainly associated with the reproductive performance, feed intake, and feed conversion ratio of LW pigs. These findings provide a theoretical basis for genetic improvements in the Chinese swine industry.

Residual network improves the prediction accuracy of genomic selection.

Genetic improvement of complex traits in animal and plant breeding depends on the efficient and accurate estimation of breeding values. Deep learning methods have been shown to be not superior over traditional genomic selection (GS) methods, partially due to the degradation problem (i.e. with the increase of the model depth, the performance of the deeper model deteriorates). Since the deep learning method residual network (ResNet) is designed to solve gradient degradation, we examined its performance and factors related to its prediction accuracy in GS. Here we compared the prediction accuracy of conventional genomic best linear unbiased prediction, Bayesian methods (BayesA, BayesB, BayesC, and Bayesian Lasso), and two deep learning methods, convolutional neural network and ResNet, on three datasets (wheat, simulated and real pig data). ResNet outperformed other methods in both Pearson's correlation coefficient (PCC) and mean squared error (MSE) on the wheat and simulated data. For the pig backfat depth trait, ResNet still had the lowest MSE, whereas Bayesian Lasso had the highest PCC. We further clustered the pig data into four groups and, on one separated group, ResNet had the highest prediction accuracy (both PCC and MSE). Transfer learning was adopted and capable of enhancing the performance of both convolutional neural network and ResNet. Taken together, our findings indicate that ResNet could improve GS prediction accuracy, affected potentially by factors such as the genetic architecture of complex traits, data volume, and heterogeneity.

Genomic Prediction of Growth Traits in Yorkshire Pigs of Different Reference Group Sizes Using Different Estimated Breeding Value Models.

The need for sufficient reference population data poses a significant challenge in breeding programs aimed at improving pig farming on a small to medium scale. To overcome this hurdle, investigating the advantages of combing reference populations of varying sizes is crucial for enhancing the accuracy of the genomic estimated breeding value (GEBV). Genomic selection (GS) in populations with limited reference data can be optimized by combining populations of the same breed or related breeds. This study focused on understanding the effect of combing different reference group sizes on the accuracy of GS for determining the growth effectiveness and percentage of lean meat in Yorkshire pigs. Specifically, our study investigated two important traits: the age at 100 kg live weight (AGE100) and the backfat thickness at 100 kg live weight (BF100). This research assessed the efficiency of genomic prediction (GP) using different GEBV models across three Yorkshire populations with varying genetic backgrounds. The GeneSeek 50K GGP porcine high-density array was used for genotyping. A total of 2295 Yorkshire pigs were included, representing three Yorkshire pig populations with different genetic backgrounds-295 from Danish (small) lines from Huaibei City, Anhui Province, 500 from Canadian (medium) lines from Lixin County, Anhui Province, and 1500 from American (large) lines from Shanghai. To evaluate the impact of different population combination scenarios on the GS accuracy, three approaches were explored: (1) combining all three populations for prediction, (2) combining two populations to predict the third, and (3) predicting each population independently. Five GEBV models, including three Bayesian models (BayesA, BayesB, and BayesC), the genomic best linear unbiased prediction (GBLUP) model, and single-step GBLUP (ssGBLUP) were implemented through 20 repetitions of five-fold cross-validation (CV). The results indicate that predicting one target population using the other two populations yielded the highest accuracy, providing a novel approach for improving the genomic selection accuracy in Yorkshire pigs. In this study, it was found that using different populations of the same breed to predict small- and medium-sized herds might be effective in improving the GEBV. This investigation highlights the significance of incorporating population combinations in genetic models for predicting the breeding value, particularly for pig farmers confronted with resource limitations.

Comparative Analysis of the Ovary Transcriptome among Wanyue Black and Yorkshire Gilts Using RNA-Seq.

Pubertal genetic variations between the indigenous Chinese Wanyue Black pig breed and the imported Yorkshire breed significantly impact their reproductive capacity. In order to identify the differentially expressed genes, gene networks, and metabolic pathways in ovary transcriptome of gilts, the serum hormone levels were analyzed by ELISA, and RNA-seq was performed to analyze ovarian genes. Our results reveal higher estradiol (E2) levels in Wanyue black gilts compared to Yorkshire gilts, while Yorkshire gilts exhibit elevated progesterone (P4) and GnRH levels. We identified a total of 154 differentially expressed genes (DEGs), with 87 up-regulated and 67 down-regulated genes in the Wanyue black gilts ovaries compared to the Yorkshire gilts. GO enrichment analysis unveiled the participation of DEGs in processes such as "Reproduction", "Reproductive system development", and "Ovarian follicle development". Moreover, KEGG enrichment analysis revealed the involvement of DEGs in multiple signaling pathways associated with hormone biosynthesis and puberty, encompassing "Steroid hormone biosynthesis", "Estrogen signaling pathway", and "Prolactin signaling pathway". The subsequent bioinformatics analysis identified nine functional genes that potentially contribute to the disparity in ovaries between Wanyue black gilts and Yorkshire gilts. This study offers significant insights into the endocrine and genetic aspects of pubertal development in gilts.

Protein Post-Translational Modifications Based on Proteomics: A Potential Regulatory Role in Animal Science.

Genomic studies in animal breeding have provided a wide range of references; however, it is important to note that genes and mRNA alone do not fully capture the complexity of living organisms. Protein post-translational modification, which involves covalent modifications regulated by genetic and environmental factors, serves as a fundamental epigenetic mechanism that modulates protein structure, activity, and function. In this review, we comprehensively summarize various phosphorylation and acylation modifications on metabolic enzymes relevant to energy metabolism in animals, including acetylation, succinylation, crotonylation, ß-hydroxybutylation, acetoacetylation, and lactylation. It is worth noting that research on animal energy metabolism and modification regulation lags behind the demands for growth and development in animal breeding compared to human studies. Therefore, this review provides a novel research perspective by exploring unreported types of modifications in livestock based on relevant findings from human or animal models.

Genome-Wide Detection for Runs of Homozygosity in Baoshan Pigs Using Whole Genome Resequencing.

Baoshan pigs (BS) are a local breed in Yunnan Province that may face inbreeding owing to its limited population size. To accurately evaluate the inbreeding level of the BS pig population, we used whole-genome resequencing to identify runs of homozygosity (ROH) regions in BS pigs, calculated the inbreeding coefficient based on pedigree and ROH, and screened candidate genes with important economic traits from ROH islands. A total of 22,633,391 SNPS were obtained from the whole genome of BS pigs, and 201 ROHs were detected from 532,450 SNPS after quality control. The number of medium-length ROH (1-5 Mb) was the highest (98.43%), the number of long ROH (>5 Mb) was the lowest (1.57%), and the inbreeding of BS pigs mainly occurred in distant generations. The inbreeding coefficient FROH, calculated based on ROH, was 0.018 ± 0.016, and the FPED, calculated based on the pedigree, was 0.027 ± 0.028, which were positively correlated. Forty ROH islands were identified, containing 507 genes and 891 QTLs. Several genes were associated with growth and development (IGFALS, PTN, DLX5, DKK1, WNT2), meat quality traits (MC3R, ACSM3, ECI1, CD36, ROCK1, CACNA2D1), and reproductive traits (NPW, TSHR, BMP7). This study provides a reference for the protection and utilization of BS pigs.

Metformin Attenuates Neutrophil Recruitment through the H3K18 Lactylation/Reactive Oxygen Species Pathway in Zebrafish.

Beyond its well-established role in diabetes management, metformin has gained attention as a promising therapeutic for inflammation-related diseases, largely due to its antioxidant capabilities. However, the mechanistic underpinnings of this effect remain elusive. Using in vivo zebrafish models of inflammation, we explored the impact of metformin on neutrophil recruitment and the underlying mechanisms involved. Our data indicate that metformin reduces histone (H3K18) lactylation, leading to the decreased production of reactive oxygen species (ROS) and a muted neutrophil response to both caudal fin injury and otic vesicle inflammation. To investigate the precise mechanisms through which metformin modulates neutrophil migration via ROS and H3K18 lactylation, we meticulously established the correlation between metformin-induced suppression of H3K18 lactylation and ROS levels. Through supplementary experiments involving the restoration of lactate and ROS, our findings demonstrated that elevated levels of both lactate and ROS significantly promoted the inflammatory response in zebrafish. Collectively, our study illuminates previously unexplored avenues of metformin's antioxidant and anti-inflammatory actions through the downregulation of H3K18 lactylation and ROS production, highlighting the crucial role of epigenetic regulation in inflammation and pointing to metformin's potential in treating inflammation-associated conditions.

1.63-billion-year-old multicellular eukaryotes from the Chuanlinggou Formation in North China.

Multicellularity is key to the functional and ecological success of the Eukarya, underpinning much of their modern diversity in both terrestrial and marine ecosystems. Despite the widespread occurrence of simple multicellular organisms among eukaryotes, when this innovation arose remains an open question. Here, we report cellularly preserved multicellular microfossils (Qingshania magnifica) from the ~1635-million-year-old Chuanlinggou Formation, North China. The fossils consist of large uniseriate, unbranched filaments with cell diameters up to 190 micrometers; spheroidal structures, possibly spores, occur within some cells. In combination with spectroscopic characteristics, the large size and morphological complexity of these fossils support their interpretation as eukaryotes, likely photosynthetic, based on comparisons with extant organisms. The occurrence of multicellular eukaryotes in Paleoproterozoic rocks not much younger than those containing the oldest unambiguous evidence of eukaryotes as a whole supports the hypothesis that simple multicellularity arose early in eukaryotic history, as much as a billion years before complex multicellular organisms diversified in the oceans.

Using genomic selection to improve the accuracy of genomic prediction for multi-populations in pigs.

The size of the reference group is among the most critical determinants of genomic estimated breeding values (GEBVs) accuracy. However, small- and medium-sized pig farms often need help accumulating adequate reference data, posing significant challenges to breeding programs. To solve this problem, exploring the potential benefits of combining reference groups of different sizes is necessary to improve GEBV accuracy. The primary objective of this investigation was to assess a more effective statistical model for combined multi-populations and its potential to enhance the accuracy of GEBVs for small and medium populations. Three populations were simulated using the QMSim software, each consisting of different sizes (300, 600, and 1 500, respectively). To assess the impact of heritability on the accuracy of GEBVs, four different levels of heritability (0.05, 0.15, 0.35, and 0.5) were simulated. Simultaneously, to investigate the impact of kinship on multi-populations, the study created four distinct scenarios for the three sizes of populations. These scenarios included: (1) the three groups are all independent, (2) the large group and the small group with a familial connection (n = 1 800), a middle group (n = 600) acting independently with no kinship, (3) the large group with a familial connection to the middle group (n = 2 100) but no connection to the small group (n = 300), and (4) the small group with a familial connection to the middle group (n = 900), while the large group (n = 1 500) acted independently with no kinship. This study evaluates and compares the accuracy of predicting breeding values using four different methods, including genomic best linear unbiased prediction (GBLUP), single-stepGBLUP (ssGBLUP), and two Bayesian models (Bayes A and Bayes B), with varying sizes of reference groups. In each scenario, three different prediction strategies were compared: (1) Merging all three different sizes of populations for predicting, (2) predicting each independent population separately, and (3) the other two populations predict the population. Our findings reveal that combining populations enhances the Bayesian models, with Bayes B yielding the highest accuracy. In independent populations, the best linear unbiased prediction (BLUP) models demonstrated the highest accuracy. However, in cases where populations were related and the heritability was high, the Bayes B model exhibited the highest overall accuracy (slightly higher than BLUP models) in the independent population. Our results underscore the importance of considering population combinations when using genetic models to predict breeding values, particularly for pig farmers with limited resources.

l-valine supplementation disturbs vital molecular pathways and induces apoptosis in mouse testes.

The branched-chain amino acids (BCAAs: leucine, isoleucine and valine) are essential for animal growth and metabolic health. However, the effect of valine on male reproduction and its underlying molecular mechanism remain largely unknown. Here, we showed that l-valine supplementation (0.30% or 0.45%, water drinking for 3 weeks) did not change body and testis weights, but significantly altered morphology of sertoli cells and germ cells within seminiferous tubule, and enlarged the space between seminiferous tubules within mouse testis. l-valine treatment (0.45%) increased significantly the Caspase3/9 mRNA levels and CASPASE9 protein levels, therefore induced apoptosis of mouse testis. Moreover, gene expression levels related to autophagy (Atg5 and Lamb3), DNA 5 mC methylation (Dnmt1, Dnmt3a, Tet2 and Tet3), RNA m6A methylation (Mettl14, Alkbh5 and Fto), and m6A methylation binding proteins (Ythdf1/2/3 and Igf2bp1/2) were significantly reduced. Protein abundances of ALKBH5, FTO and YTHDF3 were also significantly reduced, but not for ATG5 and TET2. Testis transcriptome sequencing detected 537 differentially expressed genes (DEGs, 26 up-regulated and 511 down-regulated), involved in multiple important signaling pathways. RT-qPCR validated 8 of 9 DEGs (Cd36, Scd1, Insl3, Anxa5, Lcn2, Hsd17b3, Cyp11a1, Cyp17a1 and Agt) to be decreased significantly, consistent with RNA-seq results. Taken together, l-valine treatment could disturb multiple signaling pathways (autophagy and RNA methylation etc.), and induce apoptosis to destroy the tissue structure of mouse testis.

Integrated of multi-omics and molecular docking reveal PHGDH, PSAT1 and PSPH in the serine synthetic pathway as potential targets of T-2 toxin exposure in pig intestinal tract.

T-2 toxin (T-2) with a molecular weight of 466.52 g/mol is an inevitable mycotoxin in food products and feeds, posing a significant threat to human and animal health. However, the underlying molecular mechanisms of the cytotoxic effects of T-2 exposure on porcine intestinal epithelial cells (IPEC-J2) remain unclear. Here, we investigated the cytotoxic effects of T-2 exposure on IPEC-J2 through the detection of cell viability, cell morphology, mitochondrial membrane potential, ROS, apoptosis and autophagy. Further transcriptomic and proteomic analyses of IPEC-J2 upon T-2 exposure were performed by using RNA-seq and TMT techniques. A total of 546 differential expressed genes (DEGs) and 269 differentially expressed proteins (DEPs) were detected. Among these, 24 common DEGs/DEPs were involved in IPEC-J2 upon T-2 exposure. Interestingly, molecular docking analysis revealed potential interactions between T-2 and three key enzymes (PHGDP, PSAT1, and PSPH) in the serine biosynthesis pathway. Besides, further experimental showed that PSAT1 knockdown exacerbated T-2-induced oxidative damage. Together, our findings indicated that the serine biosynthesis pathway including PHGDP, PSAT1, PSPH genes probably acts critical roles in the regulation of T-2-induced cell damage. This study provided new insights into the global molecular effects of T-2 exposure and identified the serine biosynthesis pathway as molecular targets and potential treatment strategies against T-2.

Circadian clock1a coordinates neutrophil recruitment via nfe212a/duox-reactive oxygen species pathway in zebrafish.

Neutrophil recruitment to inflammatory sites appears to be an evolutionarily conserved strategy to fight against exogenous insults. However, the rhythmic characteristics and underlying mechanisms of neutrophil migration on a 24-h timescale are largely unknown. Using the advantage of in vivo imaging of zebrafish, this study explored how the circadian gene clock1a dynamically regulates the rhythmic recruitment of neutrophils to inflammatory challenges. We generated a clock1a mutant and found that neutrophil migration is significantly increased in caudal fin injury and lipopolysaccharide (LPS) injection. Transcriptome sequencing, chromatin immunoprecipitation (ChIP), and dual-luciferase reporting experiments suggest that the clock1a gene regulates neutrophil migration by coordinating the rhythmic expression of nfe212a and duox genes to control the reactive oxygen species (ROS) level. This study ultimately provides a visual model to expand the understanding of the rhythmic mechanisms of neutrophil recruitment on a circadian timescale in a diurnal organism from the perspective of ROS.

Genomic Scan for Runs of Homozygosity and Selective Signature Analysis to Identify Candidate Genes in Large White Pigs.

Large White pigs are extensively utilized in China for their remarkable characteristics of rapid growth and the high proportion of lean meat. The economic traits of pigs, comprising reproductive and meat quality traits, play a vital role in swine production. In this study, 2295 individuals, representing three different genetic backgrounds Large White pig populations were used: 500 from the Canadian line, 295 from the Danish line, and 1500 from the American line. The GeneSeek 50K GGP porcine HD array was employed to genotype the three pig populations. Firstly, genomic selective signature regions were identified using the pairwise fixation index (FST) and locus-specific branch length (LSBL). By applying a top 1% threshold for both parameters, a total of 888 candidate selective windows were identified, harbouring 1571 genes. Secondly, the investigation of regions of homozygosity (ROH) was performed utilizing the PLINK software. In total, 25 genomic regions exhibiting a high frequency of ROHs were detected, leading to the identification of 1216 genes. Finally, the identified potential functional genes from candidate genomic regions were annotated, and several important candidate genes associated with reproductive traits (ADCYAP1, U2, U6, CETN1, Thoc1, Usp14, GREB1L, FGF12) and meat quality traits (MiR-133, PLEKHO1, LPIN2, SHANK2, FLVCR1, MYL4, SFRP1, miR-486, MYH3, STYX) were identified. The findings of this study provide valuable insights into the genetic basis of economic traits in Large White pigs and may have potential use in future pig breeding programs.

Hypomethylated interferon regulatory factor 8 recruits activating protein-2α to attenuate porcine epidemic diarrhea virus infection in porcine jejunum.

Interferon regulatory factor 8 (IRF8) is a key regulator of innate immune receptor signaling that resists pathogen invasion by regulating cell growth and differentiation. Porcine epidemic diarrhea virus (PEDV) targets the intestine and damages the mucosal barrier. However, whether IRF8 regulates PEDV replication remains unclear. We revealed that PEDV infection activated IRF8 expression. Moreover, IRF8 deletion drastically promoted PEDV replication and invasion, increasing the virus copies and titers. Hypomethylation enrichment of activating protein (AP)-2α was significantly negatively correlated with high IRF8 expression, and AP-2α directly targeted the IRF8 promoter to regulate PEDV replication. Furthermore, IRF8 overexpression decreased the cellular reactive oxygen species levels and mitochondrial membrane potential and increased the antioxidant enzyme activities to alleviate PEDV-induced oxidative damage. IRF8 overexpression suppressed apoptotic gene expression, thereby inhibiting apoptosis in response to PEDV stimulation. Taken together, this study demonstrates that AP-2α is involved in PEDV-induced epigenetic modification of IRF8 to reduce cell apoptosis and oxidative stress and facilitate host resistance to PEDV in the intestinal epithelium.

GWLD: an R package for genome-wide linkage disequilibrium analysis.

Linkage disequilibrium (LD) analysis is fundamental to the investigation of the genetic architecture of complex traits (e.g. human disease, animal and plant breeding) and population structure and evolution dynamics. However, until now, studies primarily focus on LD status between genetic variants located on the same chromosome. Moreover, genome (re)sequencing produces unprecedented numbers of genetic variants, and fast LD computation becomes a challenge. Here, we have developed GWLD, a parallelized and generalized tool designed for the rapid genome-wide calculation of LD values, including conventional D/D', r2, and (reduced) mutual information (MI and RMI) measures. LD between genetic variants within and across chromosomes can be rapidly computed and visualized in either an R package or a standalone C++ software package. To evaluate the accuracy and speed of LD calculation, we conducted comparisons using 4 real datasets. Interchromosomal LD patterns observed potentially reflect levels of selection intensity across different species. Both versions of GWLD, the R package (https://github.com/Rong-Zh/GWLD/GWLD-R) and the standalone C++ software (https://github.com/Rong-Zh/GWLD/GWLD-C++), are freely available on GitHub.

A Great late Ediacaran ice age.

The emergence of the Ediacara biota soon after the Gaskiers glaciation ca. 580 million years ago (Ma) implies a possible glacial fuse for the evolution of animals. However, the timing of Ediacaran glaciation remains controversial because of poor age constraints on the ∼30 Ediacaran glacial deposits known worldwide. In addition, paleomagnetic constraints and a lack of convincing Snowball-like cap carbonates indicate that Ediacaran glaciations likely did not occur at low latitudes. Thus, reconciling the global occurrences without global glaciation remains a paradox. Here, we report that the large amplitude, globally synchronous ca. 571-562 Ma Shuram carbon isotope excursion occurs below the Ediacaran Hankalchough glacial deposit in Tarim, confirming a post-Shuram glaciation. Leveraging paleomagnetic evidence for a ∼90° reorientation of all continents due to true polar wander, and a non-Snowball condition that rules out low-latitude glaciations, we use paleogeographic reconstructions to further constrain glacial ages. Our results depict a 'Great Ediacaran Glaciation' occurring diachronously but continuously from ca. 580-560 Ma as different continents migrated through polar-temperate latitudes. The succession of radiation, turnover and extinction of the Ediacara biota strongly reflects glacial-deglacial dynamics.

Fecal Microbial Structure and Metabolic Profile in Post-Weaning Diarrheic Piglets.

(1) Background: Piglet diarrhea is one of the most serious diseases in pigs and has brought great economic losses to the pig industry. Alteration of the gut microbiota is an important factor in the etiology of piglet diarrhea. Therefore, this study aimed to analyze the differences in the gut microbial structures and fecal metabolic profile between post-weaning diarrhea and healthy Chinese Wannan Black pigs. (2) Methods: An integrated approach of 16S rRNA gene sequencing combined with LC/MS-based metabolomics was employed in this study. (3) Results: We found an increase in the relative abundance of the bacterial genus Campylobacter and a decrease in phylum Bacteroidetes and the species Streptococcus gallolyticus subsp. macedonicus. (S. macedonicus) in piglet diarrhea. Meanwhile, obvious changes in the fecal metabolic profile of diarrheic piglets were also detected, particularly higher levels of polyamines (spermine and spermidine). Moreover, there were substantial associations between the disturbed gut microbiota and the altered fecal metabolites, especially a strong positive relationship between spermidine and Campylobacter. (4) Conclusions: These observations may provide novel insights into potential etiologies related to post-weaning diarrhea and further enhance our understanding of the role of gut microbiota in host homeostasis and in modulating gut microbial structure.