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Abstracts Results of artificial insemination (AI) are affected by changes in sperm quality and the function throughout collection and preservation procedures. Proteome and metabolome alterations of sperm treated with the different procedures in goat, however, aren’t fully understood. To this end, we sought to investigate the impacts of rectal probe electrostimulation (EE) and artificial vagina (AV) semen collection methods on the quality and the cryotolerance of goat sperm, with additional focus on proteomic and metabolomic analyses. Semen samples were collected from Yunshang black goats and categorized into four groups: fresh sperm collected via AV (XAZ), fresh sperm collected via EE (XEZ), frozen sperm post-AV collection (DAZ) and frozen sperm post-EE collection (DEZ). Four comparisons (XAZ vs. XEZ, DAZ vs. XAZ, DEZ vs. XEZ, DAZ vs. DEZ) were performed, respectively. This study first evaluated sperm motility, acrosome integrity, plasma membrane integrity, mitochondrial activity, and reactive oxygen species (ROS) levels. The results indicated that there were no significant differences in fresh sperm quality parameters between the EE and AV methods. However, notable differences emerged post-cryopreservation. Specifically, the AV method proved more advantageous in preserving the motility, integrities of acrosome and plasma membrane, mitochondrial activity of frozen sperm compared to the EE method. Through the multi-omics approaches, a total of 210 differentially abundant proteins (DAPs) related to sperm characteristics and function were identified across the four comparations. Moreover, 32 differentially abundant metabolites (DAMs) were detected. Comprehensive bioinformatics analysis underscored significant molecular pathways in the co-enrichment of DAPs and DAMs, particularly focusing on the citrate cycle, ROS, oxidative phosphorylation, and glycine, serine, and threonine metabolism etc. We elucidated the differential impacts of AV and EE collection methods on the quality and cryotolerance of goat semen from omics perspectives, which offer a critical foundation for further exploration into optimizing semen collection and cryopreservation techniques in goat breeding program.

Unmanned aerial vehicle (UAV)-enabled edge computing is emerging as a potential enabler for Artificial Intelligence of Things (AIoT) in the forthcoming sixth-generation (6G) communication networks. With the use of flexible UAVs, massive sensing data is gathered and processed promptly without considering geographical locations. Deep neural networks (DNNs) are becoming a driving force to extract valuable information from sensing data. However, the lightweight servers installed on UAVs are not able to meet the extremely high requirements of inference tasks due to the limited battery capacities of UAVs. In this work, we investigate a DNN model placement problem for AIoT applications, where the trained DNN models are selected and placed on UAVs to execute inference tasks locally. It is impractical to obtain future DNN model request profiles and system operation states in UAV-enabled edge computing. The Lyapunov optimization technique is leveraged for the proposed DNN model placement problem. Based on the observed system overview, an advanced online placement (AOP) algorithm is developed to solve the transformed problem in each time slot, which can reduce DNN model transmission delay and disk I/O energy cost simultaneously while keeping the input data queues stable. Finally, extensive simulations are provided to depict the effectiveness of the AOP algorithm. The numerical results demonstrate that the AOP algorithm can reduce 18.14% of the model placement cost and 29.89% of the input data queue backlog on average by comparing it with benchmark algorithms.

Abstract Plasma membrane damage in vitrified oocytes is closely linked to mitochondrial dysfunction. However, the mechanism underlying mitochondria-regulated membrane stability is not elucidated. A growing body of evidence indicates that mitochondrial activity plays a pivotal role in cell adaptation. Since mitochondria work at a higher temperature than the constant external temperature of the cell, we hypothesize that suppressing mitochondrial activity would protect oocytes from extreme stimuli during vitrification. Here we show that metformin suppresses mitochondrial activity by reducing mitochondrial temperature. In addition, metformin affects the developmental potential of oocytes and improves the survival rate after vitrification. Transmission electron microscopy results show that mitochondrial abnormalities are markedly reduced in vitrified oocytes pretreated with metformin. Moreover, we find that metformin transiently inhibits mitochondrial activity. Interestingly, metformin pretreatment decreases cell membrane fluidity after vitrification. Furthermore, transcriptome results demonstrate that metformin pretreatment modulates the expression levels of genes involved in fatty acid elongation process, which is further verified by the increased long-chain saturated fatty acid contents in metformin-pretreated vitrified oocytes by lipidomic profile analysis. In summary, our study indicates that metformin alleviates cryoinjuries by reducing membrane fluidity via mitochondrial activity regulation.

Sperm cryopreservation is an approach to preserve sperm cells in liquid nitrogen or other cryogenic media for future use in assisted reproductive technologies, such as in vitro fertilization or artificial insemination. Sperm cryopreservation has been extensively used in the dairy industry and has attained excellent results after artificial insemination. However, for small ruminants the application of sperm cryopreservation is limited, due to the poor quality of frozen semen and special characteristics of the reproductive female tract. In order to improve post-thaw semen quality various cryoprotectants are used. Currently, many types of cryoprotectants, such as permeable organic solvents, sugars, antioxidants, and natural or synthetic ice blockers, have been tested on small ruminants’ sperm cryopreservation. Among them, trehalose; has shown potential acting as an excellent cryoprotectant for semen freezing. While, the exact roles and action mechanisms of trehalose during cryopreservation remain unclear. In this review, we systematically summarized the present usage status, potential action mechanisms, and future application prospects of trehalose in small-ruminant sperm cryopreservation.

T-2 toxin, a trichothecene mycotoxin, is an important environmental pollutant that poses a threat globally to the health of humans and animals. It has been found to induce nephrotoxicity; however, the precise molecular mechanism involved remains unclear. In this study, mice were administered at a single dose of 2 mg/kg body weight T-2 toxin intraperitoneally, and kidney function and ultrastructural observations were assessed after 1 d, 3 d, and 7 d. Histopathological findings revealed that exposure to T-2 toxin caused noticeable tubular degeneration, necrosis and epithelial cell shedding in mouse kidneys. Transmission electron microscopy indicated that exposure to T-2 toxin caused mitochondrial swelling and vacuolization. Transcriptomic data revealed significant differences in the expression of 1122, 58, and 391 genes in kidney tissues 1 d, 3 d, or 7 d after T-2 toxin exposure, respectively. Moreover, after 1 d, the downregulated differentially expressed genes (DEGs) were found to be involved in the cell cycle, p53 signaling, and cellular senescence pathways, while the upregulated DEGs were found to be associated with the ribosomal pathway. Temporal changes in gene expression patterns (i.e., after 3 d and 7 d) and disturbances in cellular metabolism during the recovery period (7 d) were detected in mouse kidneys after exposure to T-2 toxin. In conclusion, this study is the first to provide a comprehensive comparative transcriptomic analysis of T-2 toxin exposure-induced nephrotoxicity-related gene regulation at different time points and to investigate the mechanism underlying the nephrotoxicity of T-2 toxin at the mRNA expression level.

At present, there are few reports about the proteomics changes provoked by butylated hydroxytoluene (BHT) supplementation on cryopreserved semen in mammals. Thus, we aimed to evaluate the effects of different concentrations of BHT on goat sperm and to investigate the proteomics changes of adding BHT to cryopreserved goat (Capra hircus) sperm. Firstly, semen samples were collected from four goats, and frozen in the basic extenders containing different concentrations of BHT (0.5 mM, 1.0 mM, 2.0 mM) and a control without BHT, respectively. After thawing, the protective effects of dose-dependent replenished BHT to the freezing medium on post-thaw sperm motility, integrities of plasma membrane and acrosome, reactive oxygen species levels were confirmed, with 0.5 mM BHT being the best (B group) as compared to the control (without BHT, C group). Afterwards, TMT-based quantitative proteomic technique was performed to profile proteome of the goat sperm between C group and B group. Parallel reaction monitoring was used to confirm reliability of the data. Overall, 2,476 proteins were identified and quantified via this approach. Comparing the C and B groups directly (C vs. B), there were 17 differentially abundant proteins (DAPs) po-tentially associated with sperm characteristics and functions were identified, wherein three were upregulated and 14 were downregulated, respectively. GO annotation analysis demonstrated the potential involvement of the identified DAPs in metabolic process, multi-organism process, reproduction, reproductive process, and cellular process. KEGG enrichment analysis further indicated their potential roles in renin-angiotensin system and glutathione metabolism pathways. Together, this novel study clearly shows that BHT can effectively improve quality parameters and fertility potential of post-thawed goat sperm at the optimal concentration, and its cryoprotection may be realized through regulation of sperm metabolism and antioxidative capability from the perspective of sperm proteomic modification.

Reinforcement Learning (RL) is an effective method to solve stochastic sequential decision-making problems. This is a problem description common to supply chain operations, however, most RL algorithms are tailored for game-based benchmarks. Here, we propose a deep RL method tailored for supply chain problems. The proposed algorithm deploys a derivative free approach to balance exploration and exploitation of the neural policy’s parameter space, providing means to avoid low quality local optima. Furthermore, the method allows consideration of risk-sensitive formulations to learn a policy that optimizes, for example, the conditional value-at-risk. The capabilities of our algorithm are tested on a multi-echelon supply chain problem, and several combinatorial optimization problems. The results empirically demonstrate the method’s improved sample efficiency compared to the benchmark algorithm proximal policy optimization, and superior performance to shrinking horizon mixed integer formulations. Additionally, its risk-sensitive policy can offer protection from low probability, high severity scenarios. Finally, we provide a sensitivity analysis for technical intuition.

Abstract Sperm motility is an index tightly associated with male fertility. A close relationship between seminal plasma and sperm motility has been confirmed. This study was to assess the protein and metabolite profiles of seminal plasma obtained from adult goats with high or low sperm motility using the proteomic and metabolomic strategies. In total, 2098 proteins were found. 449 differentially abundant proteins (DAPs) were identified, and 175 DAPs were enriched in the high motility group. The obtained DAPs primarily exist in cytoplasma and extra-cellular portion. The Gene Ontology enrichment analysis demonstrated the main functional roles of these DAPs in regulating biological process, metabolic process of organic substances, cellular-metabolic process, primary-metabolic process, metabolic process of nitrogen compounds, etc. Additionally, the Kyoto-Encyclopedia of Genes and Genomes (KEGG) analysis revealed that these DAPs were primarily involved in phosphatidylinositol signaling system, salivary secretion, proteasome, apoptosis, mitophagy-animal, etc. Aided by the parallel reaction monitoring technology, the abundance changing pattern of 19 selected DAPs was consistent with that of the corresponding proteins obtained by TMT. A total of 4603 metabolites were identified in seminal plasma. 1857 differential metabolites were found between the high motility group and the low motility group, and 999 metabolites were up-regulated in the high motility group. The KEGG analysis demonstrated the primary involvement of the differential metabolites in metabolic and synthetic activities. In conclusion, we first established the proteome and metabolome databank of goat seminal plasma, detecting some proteins and metabolites which may affect sperm motility. This study will be valuable for understanding mechanisms leading to poor sperm motility.

Cryopreservation of embryos has been confirmed to cause oxidative stress as a factor responsible for impaired developmental competence. Currently, astaxanthin (Ax) raises considerable interest as a strong exogenous antioxidant and for its potential in reproductive biology. The present study aimed to investigate the beneficial effects of Ax supplementation during in vitro culture of vitrified porcine zygotes and the possible underlying mechanisms. First, the parthenogenetic zygotes were submitted to vitrification and then cultured in the medium added with various concentrations of Ax (0, 0.5, 1.5, and 2.5 μM). Supplementation of 1.5 μM Ax achieved the highest blastocyst yield and was considered as the optimal concentration. This concentration also improved the blastocyst formation rate of vitrified cloned zygotes. Moreover, the vitrified parthenogenetic zygotes cultured with Ax exhibited significantly increased mRNA expression of CDX2, SOD2, and GPX4 in their blastocysts. We further analyzed oxidative stress, mitochondrial and lysosomal function in the 4-cell embryos and blastocysts derived from parthenogenetic zygotes. For the 4-cell embryos, vitrification disturbed the levels of reactive oxygen species (ROS) and glutathione (GSH), and the activities of mitochondria, lysosome and cathepsin B, and Ax supplementation could fully or partially rescue these values. The blastocysts obtained from vitrified zygotes showed significantly reduced ATP content and elevated cathepsin B activity, which also was recovered by Ax supplementation. There were no significant differences in other parameters mentioned above for the resultant blastocysts. Furthermore, the addition of Ax significantly enhanced mitochondrial activity and reduced lysosomal activity in resultant blastocysts. In conclusion, these findings revealed that Ax supplementation during the culture period improved subsequent embryonic development and quality of porcine zygotes after vitrification and might be used to ameliorate the recovery culture condition for vitrified embryos.

Yunnan semi-fine wool sheep are among the most important cultivated sheep breeds in China. However, their population structure, genetic characteristics and traits of interest are poorly studied. In this study, we systematically studied the population characteristics and selection signatures of 40 Yunnan semi-fine wool sheep using SNPs obtained from whole-genome resequencing data. A total of 1393 Gb of clean data were acquired. The mapping rate against the reference genome was 91.23% on average (86.01%–92.26%), and the average sequence depth was 9.51X. After filtering, 28,593,198 SNPs and 4,725,259 indels with high quality were obtained. The heterozygosity rate, inbreeding coefficient and effective population size of the sheep were calculated to preliminarily explore their genetic characteristics. The average heterozygosity rate was 0.264, the average inbreeding coefficient was 0.0099, and the effective population size estimated from the heterozygote excess (HE) was 242.9. Based on the Tajima’s D and integrated haplotype score (iHS) approaches, 562 windows and 11,356 core SNPs showed selection signatures in the Yunnan semi-fine wool sheep population. After genome annotation and gene enrichment analysis, we found traces of early domestication in sensory organs, behavioural activity and the nervous system as well as adaptive changes in reproductive and wool traits under selection in this population. Some selected genes related to litter size, including FSHR, BMPR1B and OXT, were identified as being under selection. Specific missense mutations of the FSHR gene that differed from the reference genome were also identified in the population, and we found some SNP variations that may affect litter size. Our findings provide a theoretical basis for the conservation and utilization of Yunnan semi-fine wool sheep. Furthermore, our results reveal some changes common to sheep after domestication and provide a new opportunity to investigate the genetic variation influencing fecundity within a population evolving under artificial selection.

The dynamic changes in protein expression are well known to be required for oocyte meiotic maturation. Although proteomic analysis has been performed in porcine oocytes during in vitro maturation, there is still no full data because of the technical limitations at that time. Here, a novel tandem mass tag (TMT)-based quantitative approach was used to compare the proteomic profiles of porcine immature and in vitro mature oocytes. The results of our study showed that there were 763 proteins considered with significant difference−450 over-expressed and 313 under-expressed proteins. The GO and KEGG analyses revealed multiple regulatory mechanisms of oocyte nuclear and cytoplasmic maturation such as spindle and chromosome configurations, cytoskeletal reconstruction, epigenetic modifications, energy metabolism, signal transduction and others. In addition, 12 proteins identified with high-confidence peptide and related to oocyte maturation were quantified by a parallel reaction monitoring technique to validate the reliability of TMT results. In conclusion, we provided a detailed proteomics dataset to enrich the understanding of molecular characteristics underlying porcine oocyte maturation in vitro.

Cryopreservation of porcine cloned zygotes has important implications for biotechnology and biomedicine research; however, lower embryo developmental potential remains an urgent problem to be resolved. For exploring the sublethal cryodamages during embryo development, this study was designed to acquire the mRNA and long non-coding RNA (lncRNA) profiles of 2-cells, 4-cells and blastocysts derived from vitrified porcine cloned zygotes using transcriptome sequencing. We identified 167 differentially expressed (DE) mRNAs and 516 DE lncRNAs in 2-cell stage, 469 DE mRNAs and 565 lncRNAs in 4-cell stage, and 389 DE mRNAs and 816 DE lncRNAs in blastocyst stage. Functional enrichment analysis revealed that the DE mRNAs during embryo development were involved in many regulatory mechanisms related to cell cycle, cell proliferation, apoptosis, metabolism and others. Moreover, the target genes of DE lncRNAs in the three embryonic stages were also enriched in many key GO terms or pathways such as “defense response”, “linoleic acid metabolic process”, “embryonic axis specification”, “negative regulation of protein neddylation”, etc., In conclusion, the present study provided comprehensive transcriptomic data about mRNAs and lncRNAs for the vitrified porcine cloned zygotes during different developmental stages, which contributed to further understand the potential cryodamage mechanisms responsible for impaired embryo development.

Cryopreservation of immature germinal vesicle (GV) oocytes is a promising strategy in pigs but still results in reduced oocyte quality due to inevitable cryodamages. Recently, there has been more focus on the molecular changes of oocytes after vitrification, but the alteration in the proteome level remains elusive. The aim of this study therefore was to decipher the proteomic characteristics of porcine GV oocytes following vitrification and in vitro maturation (IVM) by using tandem mass tag (TMT)-based quantitative approach and bioinformatics analysis. A total of 4,499 proteins were identified, out of which 153 presented significant difference. There were 94 up-regulated and 59 down-regulated proteins expressed differentially in the vitrified oocytes. Functional classification and enrichment analyses revealed that many of these proteins were involved in metabolism, signal transduction, response to stimulus, immune response, complement, coagulation cascades, and so on. Moreover, a parallel reaction monitoring technique validated the reliability of TMT data through quantitative analysis for 10 candidate proteins. In conclusion, our results provided a novel perspective of proteomics to comprehend the quality change in the vitrified porcine GV oocytes after IVM.