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"Demonstration farms" can disseminate knowledge on farming practices and help to promote animal welfare. When on-farm visits are impractical, remote demonstrations are a feasible alternative. This study used videos of higher welfare beef, fish and free-range egg farms in China. It aimed to determine whether the videos affected attitudes and intentions toward animal welfare and whether such videos are useful training tools. Participants indicated a high acceptability of demonstration farm videos for learning about their industry and the needs of animals. Videos shifted participant attitudes toward animal welfare, but only when actively engaged in rating the farm on specific characteristics. Attitude changes suggested participants gained a greater understanding of animal welfare, a greater intention to improve on-farm welfare, and more confidence in peer support for welfare innovations after viewing the video. The findings indicate videos of demonstration farms are useful for remote training but passive viewing may be insufficient to create change, and outcomes should be monitored for success. [ABSTRACT FROM AUTHOR]

Wireless positioning and tracking technology are key technologies in applying wireless sensor networks and have vital research significance and application value. In this paper, in terms of positioning multiple non-coincident dynamic targets, aiming at the problem of low precision and large computational complexity when locating multiple dynamic targets by the two-step least squares algorithm and the constrained total least squares algorithm, an improved constrained total least squares algorithm is proposed. This algorithm fully considers the constraints, introduces the Lagrangian multiplier technology and the quasi-Newton BFGS iterative formula, avoids the calculation of the Hessian matrix, reduces the amount of calculation, and improves the positioning accuracy. Simulation experiments show that when the measurement error and sensor position error are moderate, the ICTLS positioning algorithm has a smaller RMSE than the TSWLS and CTLS positioning algorithms, showing higher positioning accuracy and stronger robustness. Secondly, aiming at the problem that the target is close to the reference node or any coordinate axis causes the positioning error of the traditional positioning algorithm to increase sharply, an optimized two-step least squares algorithm is proposed. This algorithm corrects the defects of the TSWLS algorithm by selecting the reference station and rotating the coordinate system again, and improves the positioning performance of the algorithm while reducing the amount of calculation. [ABSTRACT FROM AUTHOR]

The circadian misalignment of the gut microbiota caused by unusual eating times in adult animals is related to disease development. However, whether the composition and diurnal rhythm of gut microbiota can be optimized by synchronizing the window period of eating with natural eating habits to reduce the risk of diarrhea remains unclear, especially in growing animals. In this study, 108 5-week-old weaned rabbits (nocturnal animals) were randomly subjected to daytime feeding (DF) and night-restricted feeding (NRF). At age 12 weeks, six rabbits were selected from each group, and caecum and cecal contents, as well as serum samples were collected at 4-h intervals during 24 h. Overall, NRF was found to reduce the risk of diarrhea in growing rabbits, improved the diurnal rhythm and abundance of beneficial microorganisms, along with the production of beneficial metabolites, whereas reduced the abundance of potential pathogens (Synergistes , Desulfovibrio , and Alistipes). Moreover, NRF improved diurnal rhythm of tryptophan hydroxylase isoform 1 and serotonin. Furthermore, NRF strengthened the diurnal amplitude of body core temperature, and promoted the diurnal expression of intestinal clock genes (BMAL1 , CLOCK , REV-ERBα , and PER1), and genes related to the regulation of the intestinal barrier (CLAUDIN-1), and intestinal epithelial cell self-proliferation and renewal (BMI1). In vitro simulation experiments further revealed that synchronization of microbial-driven serotonin rhythm and eating activity-driven body temperature oscillations, which are important zeitgebers, could promote the diurnal expression of clock genes and CLAUDIN-1 in rabbit intestinal epithelial cells (RIEC), and enhance RIEC proliferation. This is the first study to reveal that NRF reprograms the diurnal rhythm of the gut microbiome, promotes the diurnal expression of clock genes and tight junction genes via synchronization of microbial-driven serotonin rhythm and eating activity-driven body temperature oscillations, thereby improving intestinal health and reducing the risk of diarrhea in growing rabbits. Collectively, these results provide a new perspective for the healthy feeding and management of growing animals. [ABSTRACT FROM AUTHOR]

Assisted reproductive technology (ART) is being increasingly applied to overcome infertility. However, the in vitro production process, the main procedure of ART, can lead to aberrant embryonic development and health-related problems in offspring. Understanding the mechanisms underlying the ART-induced side effects is important to improve the ART process. In this study, we carried out comparative transcriptome profiling between in vivo- (IVO) and in vitro- produced (IVP) mouse blastocysts. Our results suggested that aberrant actin organization might be a major factor contributing to the impaired development of IVP embryos. To test this, we examined the effect of actin disorganization on the development of IVP preimplantation embryos. Specific disruption of actin organization by cytochalasin B (CB) indicated that well-organized actin is essential for in vitro embryonic development. Supplementing the culture medium with 10–9 M melatonin, a cytoskeletal modulator in adult somatic cells, significantly reversed the disrupted expression patterns of genes related to actin organization, including Arhgef2, Bcl2, Coro2b, Flnc, and Palld. Immunofluorescence analysis showed that melatonin treatment of IVP embryos significantly improved the distribution and organization of actin filaments (F-actin) from the 8-cell stage onwards. More importantly, we found that melatonin alleviated the CB-mediated aberrant F-actin distribution and organization and rescued CB-induced impaired embryonic development. This is the first study to indicate that actin disorganization is implicated in impaired development of IVP embryos during the preimplantation stage. We also demonstrated that improving actin organization is a promising strategy to optimize existing IVP systems. [ABSTRACT FROM AUTHOR]

This study focused on the effect of melatonin on reprogramming with specific regard to the generation of induced pluripotent stem cells (i PSCs). Here, a secondary inducible system, which is more accurate and suitable for studying the involvement of chemicals in reprogramming efficiency, was used to evaluate the effect of melatonin on mouse i PSC generation. Secondary fibroblasts collected from all-i PSC mice through tetraploid complementation were cultured in induction medium supplemented with melatonin at different concentrations (0, 10−6, 10−7, 10−8, 10−9, or 10−10 m) or with vitamin C (50 μg/mL) as a positive control. Compared with untreated group (0.22 ± 0.04% efficiency), 10−8 (0.81 ± 0.04%), and 10−9 m (0.83 ± 0.08%) melatonin supplementation significantly improved reprogramming efficiency ( P < 0.05). Moreover, we verified that the i PSCs induced by melatonin treatment ( Mi PSCs) had the same characteristics as typical embryonic stem cells ( ESCs), including expression of the pluripotency markers Oct4, Sox2, and Nanog, the ability to form teratomas and all three germ layers of the embryo, as well as produce chimeric mice with contribution to the germ line. Interestingly, only the melatonin receptor MT2 was detected in secondary fibroblasts, while Mi PSCs and ESCs expressed MT1 and MT2 receptors. Furthermore, during the early stage of reprogramming, expression of the apoptosis-related genes p53 and p21 was lower in the group treated with 10−9 m melatonin compared with the untreated controls. In conclusion, melatonin supplementation enhances the efficiency of murine i PSC generation. These beneficial effects may be associated with inhibition of the p53-mediated apoptotic pathway. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effect of melatonin during the culture of donor cells and cloned embryos on the in vitro developmental competence and quality of cloned porcine embryos. At concentrations of 10-6 m or 10-8 m, melatonin significantly enhanced the proliferation of porcine fetal fibroblasts (PFFs), and the blastocyst rate was significantly increased in the 10-10 m melatonin-treated donor cell group. Cloned embryo development was also improved in embryo culture medium that was supplemented with 10-9 m or 10-12 m melatonin. When both donor cells and cloned embryos were treated with melatonin, the cleavage rate and total cell number of blastocysts were not significantly affected; however, the blastocyst rate was increased significantly (20.0% versus 11.7%). TUNEL assays showed that combined melatonin treatment reduced the rate of apoptotic nuclei (3.6% versus 6.1%). Gene expression analysis of the apoptosis-related genes BAX, BCL2L1, and p53 showed that the expression of BCL2L1 was significantly elevated 2.7-fold relative to the control group, while the expression of BAX and p53 was significantly decreased by 3.7-fold and 23.2-fold, respectively. In addition, we detected the expression of two melatonin receptors (MT1 and MT2) in PFFs but not in porcine cloned embryos. We conclude that exogenous melatonin enhances the development of porcine cloned embryos and improves embryo quality by inhibiting p53-mediated apoptotic pathway. The proliferation of PFFs may be mediated by receptor binding, but the beneficial effects of melatonin on embryonic development may be receptor-independent, possibly through melatonin's ability to directly scavenge free radicals. [ABSTRACT FROM AUTHOR]

Seasonal environmental shifts and improper eating habits are the important causes of diarrhea in children and growing animals. Whether adjusting feeding time at varying temperatures can modify cecal bacterial structure and improve diarrhea remains unknown. Three batches growing rabbits with two groups per batch were raised under different feeding regimens (fed at daytime vs. nighttime) in spring, summer and winter separately, and contents were collected at six time points in 1 day and used 16S rRNA sequencing to investigate the effects of feeding regimens and season on the composition and circadian rhythms of cecum bacteria. Randomized forest regression screened 12 genera that were significantly associated with seasonal ambient temperature changes. Nighttime feeding reduced the abundance of the conditionally pathogenic bacteria Desulfovibrio and Alistipes in summer and Campylobacter in winter. And also increases the circadian rhythmic Amplicon Sequence Variants in the cecum, enhancing the rhythm of bacterial metabolic activity. This rhythmic metabolic profile of cecum bacteria may be conducive to the digestion and absorption of nutrients in the host cecum. In addition, this study has identified 9 genera that were affected by the combination of seasons and feeding time. In general, we found that seasons and feeding time and their combinations affect cecum composition and circadian rhythms, and that daytime feeding during summer and winter disrupts the balance of cecum bacteria of growing rabbits, which may adversely affect cecum health and induce diarrhea risk., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 He, Zhang, Jin, Wang, Huang, Li, Guo, Liu, Liu, Liu, Geng, Li, Li, Liu and Wu.)

The misalignment of eating time and the endogenous circadian rhythm impairs the body's ability to maintain homeostasis. Although it is well established that children and growing animals differ from adults in their energy metabolism and behavioral patterns, little is known about how mistimed feeding disturbs the diurnal rhythms of behavior and metabolism in children and growing diurnal animals. In this study, growing pigs (diurnal animal) were randomly assigned to the daytime-restricted feeding (DRF) and nighttime-restricted feeding (NRF) groups for 5 weeks. Compared with observations in the DRF group, NRF disrupted the diurnal rhythm of behavior and clock genes and lowered the serum ghrelin, dopamine, and serotonin levels during the daytime and nighttime. Microbiome analysis results suggested that NRF altered the diurnal rhythm and composition of the gut microbiota, and increased log-ratios of Catenibacterium:Butyrivibrio and Streptococcus:Butyrivibrio. Based on the serum proteome, the results further revealed that rhythmic and upregulated proteins in NRF were mainly involved in oxidative stress, lipid metabolism, immunity, and cancer biological pathways. Serum physiological indicators further confirmed that NRF decreased the concentration of melatonin and fibroblast growth factor 21 during the daytime and nighttime, increased the diurnal amplitude and concentrations of very-low-density lipoprotein cholesterol, triglyceride, and total cholesterol, and increased the apolipoprotein B/ApoA1 ratio, which is a marker of metabolic syndrome. Taken together, this study is the first to reveal that mistimed feeding disrupts the behavioral rhythms of growing pigs, reprograms gut microbiota composition, reduces the serum levels of hormones associated with fighting depression and anxiety, and increases the risk of lipid metabolic dysregulation., (© 2021 Federation of American Societies for Experimental Biology.)

The high quality of induced pluripotent stem cells (iPSCs) has been determined to be high-grade chimeras that are competent for germline transmission, and viable mice can be generated through tetraploid complementation. Most of the high-quality iPSCs described to date have been male. Female iPSCs, especially fully pluripotent female iPSCs, are also essential for clinical applications and scientific research. Here, we show, for the first time, that a gender-mixed induction strategy could lead to a skewed sex ratio of iPSCs. After reprogramming, 50%, 70%, and 90% female initiating mouse embryonic fibroblasts at different male ratios resulted in 14.1 ± 6.8% (P < 0.05), 31.8 ± 5.4% (P < 0.05), and 80.1 ± 2.8% (P < 0.05) female iPSCs, respectively. Furthermore, these female iPSCs had pluripotent properties typical of embryonic stem cells. Importantly, these fully pluripotent female iPSCs could generate viable mice by tetraploid complementation. These findings indicate that high-quality female iPSCs could be derived effectively, and suggest that clinical application of female iPSCs is feasible., (© 2015 by the Society for the Study of Reproduction, Inc.)

The microtubule-associated protein ASPM (abnormal spindle-like microcephaly-associated) plays an important role in spindle organization and cell division in mitosis and meiosis in lower animals, but its function in mouse oocyte meiosis has not been investigated. In this study, we characterized the localization and expression dynamics of ASPM during mouse oocyte meiotic maturation and analyzed the effects of the downregulation of ASPM expression on meiotic spindle assembly and meiotic progression. Immunofluorescence analysis showed that ASPM localized to the entire spindle at metaphase I (MI) and metaphase II (MII), colocalizing with the spindle microtubule protein acetylated tubulin (Ac-tubulin). In taxol-treated oocytes, ASPM colocalized with Ac-tubulin on the excessively polymerized microtubule fibers of enlarged spindles and the numerous asters in the cytoplasm. Nocodazole treatment induced the gradual disassembly of microtubule fibers, during which ASPM remained colocalized with the dynamic Ac-tubulin. The downregulation of ASPM expression by a gene-specific morpholino resulted in an abnormal meiotic spindle and inhibited meiotic progression; most of the treated oocytes were blocked in the MI stage with elongated meiotic spindles. Furthermore, coimmunoprecipitation combined with mass spectrometry and western blot analysis revealed that ASPM interacted with calmodulin in MI oocytes and that these proteins colocalized at the spindle. Our results provide strong evidence that ASPM plays a critical role in meiotic spindle assembly and meiotic progression in mouse oocytes.

Vector injection into the perivitelline space has emerged as the standard delivery method to transduce lentivirus to mammalian oocytes or one-cell embryos, but its application is limited by the need for high titers of lentivirus. Herein we developed a new method by using a Piezo impact micro-manipulator for injecting low titer of lentivirus into the subzonal space of two-cell embryos or the perivitelline space of one-cell embryos that were shrunk with a highly concentrated sucrose solution. The survival rate of embryos was greater than 98% using this micromanipulation strategy, which was increased compared to the normal one-cell embryo injection method. More than 90% of injected embryos were GFP positive after subzonal injection of a lentivirus vector carrying the GFP gene with titers of 2 × 10⁸ I.U./ml. Even when a low titer of lentivirus (2 × 10⁶ I.U./ml) was used, 53.26% and 40.85% transgenic embryos were obtained after two-cell embryonic injection and one-cell sucrose treated embryonic injection, respectively. The GFP-positive rates were also greater than in the conventional method of injecting one-cell embryos (25.39%). In addition, blastocysts from the two-cell embryo injection group displayed stronger GFP fluorescence than the one-cell embryo injection groups treated with or without the sucrose solution. Increased expression of GFP suggests that the embryos obtained from this injection method have higher exogenous gene expression levels compared to previous methods. Therefore, in contrast with the traditional injection method, we have demonstrated a simplified and efficient lentivirus-mediated gene transfer method based on a low-titer virus preparation.

We recently reported that electrical activation followed by secondary chemical activation greatly enhanced the developmental competence of in vitro matured porcine oocytes fertilized by intracytoplasmic sperm injection (ICSI). We hypothesized that sperm treatment with disulfide bond reducing agents will enhance the development competence of porcine embryos produced by this ICSI procedure. We examined the effects of glutathione (GSH), dithiothreitol (DTT), GSH or DTT in combination with heparin on sperm DNA structure, paternal chromosomal integrity, pronuclear formation, and developmental competence of in vitro matured porcine oocytes after ICSI. Acridine orange staining and flow cytometry based sperm chromatin structure assay were used to determine sperm DNA integrity by calculating the cells outside the main population (COMP alphaT). No differences were observed in COMP alphaT values among GSH-treated and control groups. COMP alphaT values in GSH-treated groups were significantly lower than that in DTT-treated groups. Following ICSI, GSH treatments did not significantly alter paternal chromosomal integrity. Paternal chromosomal integrity in sperm treated with DTT plus or minus heparin was also the lowest among all groups. GSH-treated sperm yielded the highest rates of normal fertilization and blastocyst formation, which were significantly higher than that of control and DTT-treated groups. The majority of blastocysts derived from control and GSH-treated spermatozoa were diploid, whereas blastocysts derived from DTT-treated spermatozoa were haploid. In conclusion, sperm treatment with GSH enhanced the developmental capacity of porcine embryos produced by our optimized ICSI procedure.