Journal of Animal Science and Biotechnology最新文献

Background: Proteome characterization of the porcine endometrium and extraembryonic membranes is important to understand mother-embryo cross-communication. In this study, the proteome of the endometrium and chorioallantoic membrane was characterized in pregnant sows (PS) during early gestation (d 18 and 24 of gestation) and in the endometrium of non-pregnant sows (NPS) during the same days using LC-MS/MS analysis. The UniProtKB database and ClueGO were used to obtain functional Gene Ontology annotations and biological and functional networks, respectively.

Results: Our analysis yielded 3,254 and 3,457 proteins identified in the endometrium of PS and NPS, respectively; of these, 1,753 being common while 1,501 and 1,704 were exclusive to PS and NPS, respectively. In addition, we identified 3,968 proteins in the extraembryonic membranes of PS. Further analyses of function revealed some proteins had relevance for the immune system process and biological adhesion in endometrium while the embryonic chorion displayed abundance of proteins related to cell adhesion and cytoskeletal organization, suggesting they dominated the moment of endometrial remodeling, implantation and adhesion of the lining epithelia. Data are available via ProteomeXchange with identifier PXD042565.

Conclusion: This is the first in-depth proteomic characterization of the endometrium and extraembryonic membranes during weeks 3 to 4 of gestation; data that contribute to the molecular understanding of the dynamic environment during this critical period, associated with the majority of pregnancy losses.

Background: The aim of this experiment was to investigate the effect of different levels of betaine (Bet) inclusion in the diet on the intestinal health of growing rabbits under summer heat. A total of 100 weaned Qixing meat rabbits aged 35 d with body weight of 748.61 ± 38.59 g were randomly divided into 5 treatment groups: control group (basal diet) and Bet groups (basal diet + 0.75, 1.0, 1.5 or 2.0 g/kg Bet). The average daily temperature in the rabbitry during the experiment was 30.48 °C and the relative humidity was 69.44%.

Results: Dietary addition of Bet had no significant effect on growth performance and health status of growing rabbits (P > 0.05), but it increased ileal secretory immunoglobulin A content compared to the control under summer heat (P < 0.05). Addition of 0.75 g/kg Bet up-regulated jejunal IL-4, down-regulated ileal TNF-α expression (P < 0.05). The addition of 1.0 g/kg Bet increased the villi height (VH) in the jejunum (P < 0.05). Serum glucose levels were reduced, and the expression of SLC6A20 was up-regulated in jejunum and ileum of rabbits fed with 1.5 g/kg Bet (P < 0.05). When added at 2.0 g/kg, Bet reduced serum HSP70 content, increased jejunal VH, and up-regulated duodenal SLC7A6, SLC38A2, mTOR and 4EBP-2 expression (P < 0.05). Correlation analysis revealed that intestinal mTOR expression was significantly and positively correlated with SLC7A6, SLC38A2, SLC36A1 and IL-4 expression (P < 0.05).

Conclusions: Dietary addition of Bet can up-regulate the expression of anti-inflammatory factors through the AAT/mTOR pathway, improve the intestinal immune function, alleviate intestinal damage in growing rabbits caused by summer heat, and improve intestinal health.

Background: Fatty liver disease causes huge economic losses in the poultry industry due to its high occurrence and lethality rate. Three-dimensional (3D) chromatin architecture takes part in disease processing by regulating transcriptional reprogramming. The study is carried out to investigate the alterations of hepatic 3D genome and H3K27ac profiling in early fatty liver (FLS) and reveal their effect on hepatic transcriptional reprogramming in laying hens.

Results: Results show that FLS model is constructed with obvious phenotypes including hepatic visible lipid deposition as well as higher total triglyceride and cholesterol in serum. A/B compartment switching, topologically associating domain (TAD) and chromatin loop changes are identified by high-throughput/resolution chromosome conformation capture (HiC) technology. Targeted genes of these alternations in hepatic 3D genome organization significantly enrich pathways related to lipid metabolism and hepatic damage. H3K27ac differential peaks and differential expression genes (DEGs) identified through RNA-seq analysis are also enriched in these pathways. Notably, certain DEGs are found to correspond with changes in 3D chromatin structure and H3K27ac binding in their promoters. DNA motif analysis reveals that candidate transcription factors are implicated in regulating transcriptional reprogramming. Furthermore, disturbed folate metabolism is observed, as evidenced by lower folate levels and altered enzyme expression.

Conclusion: Our findings establish a link between transcriptional reprogramming changes and 3D chromatin structure variations during early FLS formation, which provides candidate transcription factors and folate as targets for FLS prevention or treatment.

Background: Dairy cows experiencing ketosis after calving suffer greater disease incidence and are at greater risk of leaving the herd. In vitro administration of beta-hydroxybutyric acid (BHBA; the primary blood ketone) has inhibitory effects on the function of bovine leukocytes. BHBA is a ligand of HCAR2 and the activation of these receptors promotes an anti-inflammatory response which may be related with immunosuppression observed in transition dairy cattle. The objective of this study was to identify and test antagonists for HCAR2 in bovine immune cells cultured with BHBA.

Results: We observed expression of HCAR2 at the protein level within lymphocytes, monocytes, and granulocytes. The proportion of cells expressing HCAR2 tended to be greater in mid-lactation compared to early lactation cows; the increase was a result of increased proportion of T and B cells expressing HCAR2. Stimulation of HCAR2 with niacin or BHBA promoted Ca²⁺ mobilization in neutrophils and mononuclear cells. Mononuclear cells treated with BHBA had diminished intracellular Ca²⁺ responses when HCAR2 was knocked down by siRNA silencing, indicating Ca²⁺ mobilization was mediated by HCAR2 signaling. Two candidate antagonists for HCAR2, synthesized from niacin (NA-1 and NA-5), were tested; monocytes and neutrophils pre-treated with NA-1 and NA-5 had reduced Ca²⁺ mobilization after incubation with BHBA. Furthermore, NA-5 but not NA-1 prevented BHBA-associated reductions in cyclic AMP.

Conclusions: We demonstrated that HCAR2 is present on bovine leukocytes and has greater expression later in lactation. We confirmed that BHBA and niacin derived HCAR2 antagonists alter bovine leukocyte activity. Our results demonstrate that both BHBA and niacin affect bovine leukocyte Ca²⁺ mobilization in a HCAR2-dependent manner.

Perennial forage plants are efficient utilizers of solar radiation and nutrients so that there is a lot of scope to increase the production of green biomass in many areas. Currently, grasses are mainly used as feeds for ruminants and equines, but there could be higher added value use for several components of the green biomass. Interest in green biorefining has risen recently motivated by the increased sustainability pressures and need to break the reliance on fossil fuels. Novel products derived from grass, such as paper and packaging, nanofibers, animal bedding, novel protein feeds, extracted proteins, biochemicals, nutraceuticals, bioactive compounds, biogas and biochar could create new sustainable business opportunities in rural areas. Most green biorefinery concepts focus on using fresh green biomass as the feedstock, but preservation of it by ensiling would provide several benefits such as all-year-around availability of the feedstock and increased stability of the press juice and press cake. The major difference between fresh and ensiled grass is the conversion of water soluble carbohydrates into fermentation end products, mainly lactic and acetic acids, that lower the pH of the silage so that it becomes stable in anaerobic conditions. This has some important consequences on the processability and quality of products, which are partly positive and partly negative, e.g., degradation of protein into peptides, amino acids and ammonia. These aspects are discussed in this review.

Background: One of the main roles of the intestinal mucosa is to protect against environmental hazards. Supplementation of xylo-oligosaccharides (XOS) is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in chickens. XOS may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier functions. The aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction (AXRF) supplementation on gut function and epithelial integrity in broiler chickens.

Methods: A total of 128 broiler chickens (Ross 308) were assigned into one of two different dietary treatments for a period of 42 d: 1) control diet consisting of a corn/soybean meal-based diet; or 2) a control diet supplemented with 0.5% XOS and 1% AXRF. Each treatment was randomly distributed across 8 pens (n = 8) with 8 chickens each. Feed intake and body weight were recorded weekly. On d 42, one male chicken per pen was selected based on average weight and euthanized, jejunum samples were collected for proteomics analysis.

Results: Dietary XOS/AXRF supplementation improved feed efficiency (P < 0.05) from d 1 to 42 compared to the control group. Proteomic analysis was used to understand the mechanism of improved efficiency uncovering 346 differentially abundant proteins (DAP) (P_adj < 0.00001) in supplemented chickens compared to the non-supplemented group. In the jejunum, the DAP translated into decreased ATP production indicating lower energy expenditure by the tissue (e.g., inhibition of glycolysis and tricarboxylic acid cycle pathways). In addition, DAP were associated with decreased epithelial cell differentiation, and migration by reducing the actin polymerization pathway. Putting the two main pathways together, XOS/AXRF supplementation may decrease around 19% the energy required for the maintenance of the gastrointestinal tract.

Conclusions: Dietary XOS/AXRF supplementation improved growth efficiency by reducing epithelial cell migration and differentiation (hence, turnover), actin polymerization, and consequently energy requirement for maintenance of the jejunum of broiler chickens.

Background: Necrotic enteritis (NE) is a major enteric disease in poultry, yet effective mitigation strategies remain elusive. Deoxycholic acid (DCA) and butyrate, two major metabolites derived from the intestinal microbiota, have independently been shown to induce host defense peptide (HDP) synthesis. However, the potential synergy between these two compounds remains unexplored.

Methods: To investigate the possible synergistic effect between DCA and butyrate in regulating HDP synthesis and barrier function, we treated chicken HD11 macrophage cells and jejunal explants with DCA and sodium butyrate (NaB), either individually or in combination, for 24 h. Subsequently, we performed RNA isolation and reverse transcription-quantitative PCR to analyze HDP genes as well as the major genes associated with barrier function. To further determine the synergy between DCA and NaB in enhancing NE resistance, we conducted two independent trials with Cobb broiler chicks. In each trial, the diet was supplemented with DCA or NaB on the day-of-hatch, followed by NE induction through sequential challenges with Eimeria maxima and Clostridium perfringens on d 10 and 14, respectively. We recorded animal mortality after infection and assessed intestinal lesions on d 17. The impact of DCA and NaB on the microbiota in the ileum and cecum was evaluated through bacterial 16S rRNA gene sequencing.

Results: We found that the combination of DCA and NaB synergistically induced multiple HDP genes in both chicken HD11 cells and jejunal explants. Additionally, the gene for claudin-1, a major tight junction protein, also exhibited synergistic induction in response to DCA and NaB. Furthermore, dietary supplementation with a combination of 0.75 g/kg DCA and 1 g/kg NaB led to a significant improvement in animal survival and a reduction in intestinal lesions compared to either compound alone in a chicken model of NE. Notably, the cecal microbiota of NE-infected chickens showed a marked decrease in SCFA-producing bacteria such as Bacteroides, Faecalibacterium, and Cuneatibacter, with lactobacilli becoming the most dominant species. However, supplementation with DCA and NaB largely restored the intestinal microbiota to healthy levels.

Conclusions: DCA synergizes with NaB to induce HDP and claudin-1 expression and enhance NE resistance, with potential for further development as cost-effective antibiotic alternatives.

Transfer RNA-derived small RNAs (tsRNAs) have been shown to be involved in early embryo development and repression of endogenous retroelements in embryos and stem cells. However, it is unknown whether tsRNAs also regulate embryo hatching. In this study, we mined the sequencing data of a previous experiment in which we demonstrated that the microRNA (miRNA) cargo of preimplantation embryonic extracellular vesicles (EVs) influences embryo development. We thus profiled the tsRNA cargo of EVs secreted by blastocysts and non-blastocysts. The majority of tsRNAs was identified as tRNA halves originating from the 5´ ends of tRNAs. Among the 148 differentially expressed tsRNAs, the 19 nt tRNA fragment (tRF) tDR-14:32-Glu-CTC-1 was found to be significantly up-regulated in EVs derived from non-blastocysts. RT-qPCR assays confirmed its significant up-regulation in non-blastocyst embryos and their conditioned medium compared to the blastocyst group (P < 0.05). Inhibition of tDR-14:32-Glu-CTC-1 by supplementing antagomirs to the conditioned medium improved embryo hatching (P < 0.05). Transcriptomic analysis of embryos treated with tDR-14:32-Glu-CTC-1 antagomirs further showed differential expression of genes that are associated with embryo hatching and implantation. In summary, tDR-14:32-Glu-CTC-1 is up-regulated in non-blastocyst embryos and their secretions, and inhibition of tDR-14:32-Glu-CTC-1 promotes embryo hatching, while influencing embryo implantation-related genes and pathways. These results indicate that embryonic EVs containing specific tRFs may regulate preimplantation embryo development.

Background: Fatty liver hemorrhage syndrome (FLHS) becomes one of the most major factors resulting in the laying hen death for caged egg production. This study aimed to investigate the therapeutic effects of Lactiplantibacillus plantarum (Lp. plantarum) FRT4 on FLHS model in laying hen with a focus on liver lipid metabolism, and gut microbiota.

Results: The FLHS model of laying hens was established by feeding a high-energy low-protein (HELP) diet, and the treatment groups were fed a HELP diet supplemented with differential proportions of Lp. plantarum FRT4. The results indicated that Lp. plantarum FRT4 increased laying rate, and reduced the liver lipid accumulation by regulating lipid metabolism (lipid synthesis and transport) and improving the gut microbiota composition. Moreover, Lp. plantarum FRT4 regulated the liver glycerophospholipid metabolism. Meanwhile, "gut-liver" axis analysis showed that there was a correlation between gut microbiota and lipid metabolites.

Conclusions: The results indicated that Lp. plantarum FRT4 improved the laying performance and alleviated FLHS in HELP diet-induced laying hens through regulating "gut-liver" axis. Our findings reveal that glycerophospholipid metabolism could be the underlying mechanism for the anti-FLHS effect of Lp. plantarum FRT4 and for future use of Lp. plantarum FRT4 as an excellent additive for the prevention and mitigation of FLHS in laying hens.

At a time when there is a growing public interest in animal welfare, it is critical to have objective means to assess the way that an animal experiences a situation. Objectivity is critical to ensure appropriate animal welfare outcomes. Existing behavioural, physiological, and neurobiological indicators that are used to assess animal welfare can verify the absence of extremely negative outcomes. But welfare is more than an absence of negative outcomes and an appropriate indicator should reflect the full spectrum of experience of an animal, from negative to positive. In this review, we draw from the knowledge of human biomedical science to propose a list of candidate biological markers (biomarkers) that should reflect the experiential state of non-human animals. The proposed biomarkers can be classified on their main function as endocrine, oxidative stress, non-coding molecular, and thermobiological markers. We also discuss practical challenges that must be addressed before any of these biomarkers can become useful to assess the experience of an animal in real-life.