Aquatic products, characterized by their high moisture content, abundant nutrients, and neutral pH, create an optimal environment for the rapid proliferation of spoilage organisms, lipid oxidation, and autolytic degradation. These factors collectively expedite the spoilage and deterioration of aquatic products during storage and transportation within the supply chain. To maintain the quality and extend the shelf-life of aquatic products, appropriate preservation methods must be implemented. The growing consumer preference for bio-preservatives, is primarily driven by consumer demands for naturalness and concerns about environmental sustainability. The present review discusses commonly employed bio-preservatives derived from plants, animals, and microorganisms and their utilization in the preservation of aquatic products. Moreover, the preservation mechanisms of bio-preservatives, including antioxidant activity, inhibition of spoilage bacteria and enzyme activity, and the formation of protective films are reviewed. Integration of bio-preservation techniques with other methods, such as nanotechnology, ozone technology, and coating technology that enhance the fresh-keeping effect are discussed. Importantly, the principal issues in the application of bio-preservation technology for aquatic products and their countermeasures are presented. Further studies and the identification of new bio-preservatives that preserve the safety and quality of aquatic products should continue.

MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate growth, development, and programmed death of cells. A newly-published study has shown that miRNA-23a could regulate 3T3-L1 adipocyte differentiation. Here, we identified miRNA-23a as a negative regulator of 3T3-L1 adipocyte differentiation again. Over-expression of miRNA-23a inhibited differentiation and decreased lipogenesis as well as down-regulated mRNA and protein expression of both peroxisome proliferator-activated receptor (PPAR) γ and fatty acid binding protein (FABP) 4, whereas knock down of miRNA-23a showed the opposite effects on differentiation as well as increasing the number of apoptotic cells. Additionally, digital gene expression profiling sequencing (DGE-Seq) was used to assay changes in gene expression profiles following alterations in the level of miR-23a. In total, over-expression or knock down of miRNA-23a significantly changed the expression of 313 and 425 genes, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that these genes were mainly involved in the stress response, immune system, metabolism, cell cycle, among other pathways. Additionally, the signal transducer and activator of transcription 1 (Stat1) was shown to be a target of miRNA-23a by computational and dual-luciferase reporter assays that indicated Janus Kinase (Jak)-Stat signal pathway was implicated in regulating adipogenesis mediated by miRNA-23a in adipocytes.

This study aimed to investigate the effects of dietary supplementation with Selenium nanoparticles (SeNPs) on lactation performance, rumen microbial communities, and metabolism in dairy goats under heat stress conditions. Twenty Guanzhong dairy goats with the same parity, similar lactation period (120 ± 15 days), and similar milk yield (1.20 ± 0.16 kg/day) were randomly divided into two groups, with 10 replicates in each group. The control group was fed a standard diet, while the experimental group was supplemented with 0.5 mg SeNPs/kg DM based on the standard diet. The pretrial period lasted for seven days, followed by a 30-day trial period. The results showed that dietary supplementation with SeNPs significantly increased milk yield, milk fat and lactose content in dairy goats, under heat stress conditions. SeNPs significantly altered the composition of the rumen microbiota, increasing the relative abundance of Prevotella and Ruminococcus while decreasing the relative abundance of Succiniclasticum. This enhanced the rumen’s ability to degrade starch and fiber under heat stress conditions. Non-targeted metabolomic analysis revealed a total of 119 differential metabolites between the two groups, indicating changes in rumen metabolism. Further correlation analysis indicated that Rumen bacterium R-21 was positively correlated with propionate, while Ralstonia insidiosa was negatively correlated with γ-glutamylcysteine. Additionally, several differential microbes, including Succinivibrio dextrinosolvens, Rummeliibacillus pycnus, Ralstonia insidiosa, and Prevotella sp BP1-56, were significantly correlated with milk composition. In conclusion, dietary supplementation with SeNPs can positively impact milk yield, milk components, and metabolism in dairy goats by improving the composition of the rumen microbiota under heat stress conditions.

This study aimed to investigate the effects of dietary supplementation with zinc oxide nanoparticles (ZnONPs) on lactation, rumen microbiota, and metabolomics in dairy goats. Twenty Guanzhong dairy goats, with comparable milk yields and in the mid-lactation stage, were randomly divided into two groups, with 10 goats in each group. The control group was fed a standard diet, while the ZnONP group received the control diet plus 30 mg ZnONPs/kg DM. The pre-trial period lasted for 7 days, followed by a trial period of 30 days. The results showed that the addition of ZnONPs increased the milk yield and milk fat content (p < 0.05). The results of rumen microbial sequencing showed that the Chao1, Observed species, and PD_whole_tree indices of the ZnONP group were higher than those of the control group. The addition of ZnONPs altered the composition of the rumen microbiota, increasing the abundance of beneficial bacteria (Prevotella and Rikenellaceae_RC9_gut_group) and decreasing the abundance of the harmful bacterium Sediminispirochaeta. Non-targeted metabolomics analysis identified a total of 261 differential metabolites between the two groups, indicating changes in rumen metabolism. Further correlation analysis revealed a positive correlation between beneficial bacteria (Rikenellaceae RC9 gut group and Anaeroplasma) and metabolites such as nicotinamide riboside, inosine, and guanosine (p < 0.05). In addition, a positive correlation was observed between milk yield and beneficial bacteria (RF39 and Clostridia vadinBB60 group), as well as between milk fat content and Quinella (p < 0.05). In summary, ZnONP supplementation can improve the structure of the rumen microbiota in dairy goats, positively influencing milk yield, milk composition, and metabolism.

The forest musk deer (FMD, Moschus berezovskii), an endangered small ruminant, is listed as a class I protected wild animals in China. However, compared to their wild counterparts, captive FMD are more prone to gastrointestinal diseases caused by gut microbial dysbiosis, which severely limits population growth and increases the risk of mortality. Active dry yeast (ADY), as a commonly used feed additive, has been widely applied in domestic livestock to improve gut microbiota and enhance immune function. Whether dietary supplementation with ADY in captive FMD contributes to gut microbial homeostasis and physical health is still unclear. Thus, the study aimed to evaluate the effects of dietary supplementation with ADY on the immunity, gut microbial composition, and serum metabolites in FMD. Fourteen male FMD from the Chongqing Institute of Medicinal Plant Cultivation (Chongqing, China), with similar initial bodyweights (7.0±0.3kg) and an average age of 4.5 years, were selected and randomly divided into two groups. The control group was fed a standard diet, while the ADY group received the standard diet supplemented with ADY at a dosage of 10 g/kg DM. ADY supplementation significantly increased the concentrations of immunoglobulin A (IgA), immunoglobulin G (IgG) and immunoglobulin M (IgM) in the serum. ADY improved the richness and diversity of the gut microbiota, increased the relative abundance of the Firmicutes and Bacteroidota, but decreased the relative abundance of the Proteobacteria. A widely targeted metabolomics analysis identified a total of 25 differential metabolites, with 10 being upregulated and 15 downregulated. Many differential metabolites, for example phosphatidylcholine, Glu-His, L-cysteine and other differential metabolites contributed to strengthening the immunity of the FMD by affecting arachidonic acid metabolism, linoleic acid metabolism, alpha-linolenic acid metabolism, and so on. Dietary supplementation with ADY positively impacts the immunity of FMD by modulating the composition of the gut microbial communities and serum metabolites.

The Chinese forest musk deer (Moschus berezovskii) is a small ruminant animal with special economic value. It is listed as a National Level I key protected species in China. However, these animals are prone to stress responses in captive environments. Epimedium, a traditional Chinese herb with aphrodisiac and anti-stress properties, may have potential benefits for the health of the captive Chinese forest musk deer, though its efficacy requires further investigation. This study aimed to evaluate the effects of dietary supplementation with Epimedium on the hormone levels, gut microbiota composition, and serum metabolism of the Chinese forest musk deer. The fourteen adult male Chinese forest musk deer with similar initial body weights (7.0 ± 0.3 kg) and an average age of 4.5 years were randomly divided into two groups, each containing seven animals. The control group was fed a standard diet without Epimedium, while the Epimedium group received the standard diet supplemented with 15 g Epimedium /kg DM. The results indicated that the inclusion of Epimedium in the diet increased dry matter intake (DMI) and improved the ratio of feed to gain (F/G), with an increase in fecal testosterone levels (p < 0.05). 16S rDNA sequencing analysis revealed that Epimedium enhanced the richness and diversity of the gut microbiota in the Chinese forest musk deer, increasing the relative abundance of beneficial bacteria such as Firmicutes, while reducing the relative abundance of the potentially pathogenic Proteobacteria (p < 0.05). A widely targeted metabolomics analysis identified 25 differential metabolites between the two groups. Significant alterations were observed in key metabolic pathways related to lipid metabolism, hormone regulation, and antioxidation, such as ovarian steroidogenesis, tyrosine metabolism, and glycerophospholipid metabolism. Furthermore, correlation analysis between gut microbiota and serum differential metabolites showed that the relative abundances of Clostridia_vadinBB60_group and UCG-010 were positively correlated with anserine and 7-ketocholesterol, respectively (p < 0.05). In conclusion, Epimedium positively influenced feed intake and hormone levels in the Chinese forest musk deer by modulating gut microbiota composition and serum metabolism.