Dairy polar lipids have demonstrated anti-inflammatory properties and protective effects on intestinal integrity, potentially mitigating the adverse impacts of weaning in piglets by modulating microbiota composition and intermediary metabolism. This study evaluated a dairy by-product rich in polar lipids on the microbiome and plasma lipid mediators of weaned piglets. A total of 240 male piglets (21 days old; 6.3 ± 0.5 kg) received either a soybean lipid-based diet (SD) or a polar lipid-based diet (PD) from weaning to day 21, followed by a common diet until day 42. Within each diet, animals were provided with one of the three milk replacers (MRs) for the first 7 days: (1) Commercial MR (CO); (2) Polar lipid-based MR (PO); and (3) Soybean lipid-based MR (SO). Fecal and plasma samples were analyzed to assess microbial composition and lipid mediator profiles. Taxonomical distance between diets increased over time, whereas MR type had no effect. The PD diet significantly altered microbiota composition, increasing, for instance, the relative abundance of Firmicutes-belonging genera of the Lachnospiraceae family (Coprococcus, Roseburia), and increasing levels of ethanolamides (e.g., AEA, PEA, SEA, and DPEA). In contrast, the SD diet increased pro-inflammatory lipid mediators (e.g., 13-HODE, 13-KODE) derived from linoleic acid. Polar lipid supplementation in diet, but not in MRs, influenced microbiota diversity and lipid mediator profiles, suggesting a potential long-term impact on immune regulation and metabolism, highlighting their potential to enhance resilience during early-life stress. Future studies should explore these effects under traditional weaning conditions or other stress models.

Subacute ruminal acidosis (SARA) is a common metabolic disorder in ruminants fed high-concentrate diets. This study hypothesized that the abundance of lactate dehydrogenase gene (ldh) in the rumen could predict the individual animal’s susceptibility to SARA. A total of 121 Hu lambs were used in the study, and ldh gene abundance was inferred by PICRUST based on 16S rRNA gene sequencing. From this population, two extreme cohorts were screened, including six lambs with the highest ldh gene abundance (HLDH group) and six lambs with the lowest ldh gene abundance (LLDH group). Subsequently, the selected lambs were challenged with a SARA-risk diet, and metagenomic sequencing technology was conducted for comparative analysis of microbial functions between the two groups. Key findings revealed that HLDH lambs exhibited the following characteristics: (1) significantly higher ldh abundance as verified by metagenomic method (P < 0.001); (2) lower rumen pH with significantly prolonged duration below the 5.8 threshold (P < 0.001); (3) a tendency to reduced total bacterial abundance (P = 0.055); (4) significantly increased molar proportion of acetate (P = 0.02); and (5) suppressed carbohydrate metabolic pathways, with tendency of decreased abundance of glycoside hydrolase family (P ≤ 0.07). Notably, the rumen microbiome of the HLDH group showed significantly higher abundance of genes encoding pyruvate ferredoxin oxidoreductase (porA-D) (P < 0.001). In conclusion, the relative abundance of the ldh gene in the rumen can serve as a biomarker for predicting the susceptibility of lambs to SARA when fed highly fermentable diets, providing theoretical basis and technical support for the early warning and precise prevention of SARA.

Weaning pigs have increased iron requirements due to rapid growth and increased red blood cell production. Traditionally, iron is supplemented using inorganic sources, such as ferrous sulfate. However, a form of iron, SQM® iron, offers better bioavailability and may have benefits for growth and gut health and reduce pathogenic bacteria. This study aimed to compare the effects of SQM® iron and ferrous sulfate on growth performance, gut health, and iron concentration in feces in nursery pigs. A total of 320 pigs weaned at 21 ± 2 days were assigned to a 2 × 2 factorial design by sanitation condition (clean or dirty) and iron source (SQM® iron or ferrous sulfate; 100 mg iron/kg diet). Results showed that pigs fed SQM® iron had greater BW on day 14 and day 28 than those fed ferrous sulfate (P < 0.05), while pigs raised under clean sanitary conditions had greater BW on day 28 than those raised under dirty conditions (P < 0.001). SQM® iron also improved average daily gain during the first 14 days and increased average daily feed intake throughout the 28-day period (P < 0.05). Additionally, pigs fed SQM® iron had higher fecal iron levels on day 21 and improved fecal scores by day 27 (P < 0.05). Under dirty conditions, SQM® iron reduced gut microbiota alpha diversity compared with ferrous sulfate under clean conditions (P < 0.05). However, this decrease in diversity did not indicate dysbiosis, as there were no significant changes in pathogenic and commensal bacteria. In conclusion, SQM® iron led to improved growth performance and fecal score in weaning pigs. While it reduced gut microbiota diversity under dirty conditions, this did not negatively affect the pigs’ gut health, suggesting that SQM® iron could be a promising alternative to traditional iron sources in pig diets.

In intensive livestock and poultry production systems, animals are often exposed to environmental and physiological stressors that impair intestinal barrier function and growth performance. Akkermansia muciniphila (AKK) has gained attention as a next-generation probiotic. However, its practical application is often hindered by its strict anaerobic nature and sensitivity to feed processing conditions. In this review, the AKK secretome is defined as the total collection of bioactive factors released or shed into the extracellular space, encompassing functional proteins, extracellular vesicles, metabolic by-products, and cell envelope-derived fragments, which collectively constitute the cell-free supernatant. This review summarizes current knowledge on the molecular components of AKK secretome and discusses its potential application as a functional feed additive. At the mechanistic level, AKK secretome supports intestinal epithelial integrity by regulating tight junctions through TLR2 signaling and promoting mucosal repair via Wnt/β-catenin-dependent stem cell activity. Individual components of the secretome, including branched-chain phospholipids, the AmTARS protein, and Amuc_1100, contribute to immune homeostasis and Nrf2-mediated redox regulation, respectively, thereby increasing host tolerance to oxidative stress. For animal production applications, AKK secretome has several practical advantages over live bacterial preparations, such as improved thermal stability during processing and reduced biosafety concerns related to bacterial translocation and antibiotic resistance gene transfer. In conclusion, the AKK secretome represents a promising and practical strategy for translating mechanistic insights into effective interventions for stress mitigation in modern animal production systems.

Viral infections continue to pose a substantial threat to global public health and animal production systems. Increasing evidence indicates that disease outcomes are largely dictated by host immune regulation rather than viral replication alone. This review presents a comprehensive nutriomic perspective on host-directed therapeutic strategies, highlighting the role of vitamins, minerals, fatty acids, and phytochemicals in modulating systemic immune responses. We explore the mechanistic convergence of these nutrients on key immunological regulatory checkpoints, including type I interferon signaling, redox homeostasis, and immune metabolism. Particular emphasis is placed on the gut–lung axis and the contribution of microbial metabolites in strengthening mucosal resilience, a critical determinant in the context of zoonotic respiratory viral infections and livestock health. By integrating clinical evidence with molecular insights, this review emphasizes the potential of precision nutritional immunomodulation to recalibrate inflammatory thresholds and enhance vaccine-specific immune responses across species. Finally, we address key translational challenges, including nutrient bioavailability within dietary and feed matrices, and propose a systems-level framework to guide future research in nutritional immunology.

Low-protein (LP) diets are increasingly adopted in poultry production to improve nitrogen efficiency. While their effects on the utilization of trace minerals have been demonstrated, the optimal supplementation strategies for these minerals remain insufficiently explored. This study investigated the interactive effects of dietary iron (Fe), copper (Cu), manganese (Mn), and zinc (Zn) supplementation in laying hens fed a 15% crude protein LP diet using a uniform design approach. A total of 1,008 Hy-Line Brown laying hens (49–60 weeks of age) were randomly allocated to 12 dietary treatments with graded combinations of the four trace elements. Production performance, egg quality, apparent nutrient digestibility, fecal mineral excretion, and duodenal metal ion transporters were assessed. Trace minerals supplementation did not affect laying performance (P > 0.05). However, significant interactions among minerals influenced egg quality, ash digestibility, and fecal mineral excretion (P < 0.05). Antagonistic interactions were observed for Cu × Zn and Fe × Zn, while Mn × Zn showed synergism (P < 0.05). Regression analyses demonstrated that optimal trace minerals combinations varied depending on the specific response variables. Given that production performance remained stable across minerals treatments, minimizing total mineral excretion was prioritized as the optimization objective. The optimization results indicate that no additional supplementation of Cu, Mn, and Zn is required, whereas 33 mg/kg of Fe represents the optimal level for minimizing total mineral excretion. These findings suggest that basal diet Cu, Mn, and Zn concentrations may largely meet the requirements of laying hens from 49 to 60 weeks of age in terms of production performance and mineral utilization. Overall, this study provides an effective approach for identifying key influencing factors and developing precision trace minerals supplementation strategies that maintain production performance while substantially reducing mineral excretion, thereby supporting environmentally sustainable poultry production.

Organoids have emerged as powerful in vitro models that bridge the gap between traditional two-dimensional cultures and in vivo studies. Over the past decade, advances in stem cell biology and extracellular matrix (ECM) engineering have enabled the establishment of organoids that partially recapitulate the structural and functional features of the mammary gland. These models have provided new opportunities to investigate mammary development, lactation biology, and breast cancer. In this review, we summarize recent progress in the establishment of mammary organoids across species, including humans, mice, and livestock. We discuss the effects of cell source, ECM, and growth factors on organoid culture. We further highlight the applications of organoid culture in mammary gland development, lactation biology, drug screening, precision medicine, and cell-based milk production. Despite the large advances achieved in the technique, the current mammary organoid culture still has many limitations due to the incomplete understanding of tissue complexity, insufficient vascularization, loss of microenvironmental interactions, and challenges in reproducibility. Emerging strategies, such as multi-organ systems, three-dimensional bioprinting, and organoids-on-a-chip, offer promising approaches to improve the physiological relevance of this technique and functional maturity. Overall, mammary organoids represent a rapidly evolving platform with broad applications. They are expected to become important platforms linking mammary biology to livestock production and next-generation dairy biomanufacturing.

This study was conducted to explore the effects of organic trace elements on milk composition, serum trace element concentrations, antioxidant and immune function, and metabolites in dairy cows. Thirty Holstein cows with similar body condition scores (3.5 ± 0.25 points) and parity were randomly divided into a control group (C), a 50% organic group (O_50), and a 100% organic group (O_100), with 10 cows in each group. The C group was fed a basal diet supplemented with 3% inorganic trace element premix, the O_50 group received 1.5% inorganic and 1.5% organic trace element premix, and the O_100 group received 3% organic trace element premix. Organic trace elements were supplemented from 21 days postpartum for 90 days. The results showed that milk protein concentration showed a linear response to organic trace element supplementation, with the highest value in the O_50 group (P < 0.05). Lactose concentration showed an increased quadratic effect (P < 0.01), whereas total solids (TS) and solid-not-fat (SNF) concentrations decreased linearly and quadratically. Serum selenium (Se) concentration increased linearly with increasing organic trace element supplementation (P < 0.05). Malondialdehyde (MDA) concentration decreased linearly (P < 0.05), whereas serum immunoglobulin A (IgA), superoxide dismutase activity, and immunoglobulin G (IgG) concentration increased significantly (P < 0.05). Liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis identified 70 and 76 differential metabolites in the O_50 and O_100 groups, respectively, compared with the C group. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that these metabolites were mainly involved in inflammatory mediator regulation, lysine degradation, sphingolipid metabolism, cytochrome P450-mediated drug metabolism, and ABC transporters. In conclusion, dietary supplementation with organic trace elements improved milk composition, antioxidant capacity, immune function, and serum metabolic profiles in dairy cows.

Developing accurate, dynamic feeding formulas for growing-finishing pigs via meta-analysis of large datasets can effectively reduce feed waste from ad libitum feeding and curb environmental pollution from nutrient excretion in feces and urine. This study aims to obtain a dynamic feed formula suitable for growing-finishing pigs through model fitting and to verify its effectiveness. We utilized data from 523 treatments across 112 studies to establish the relationship between daily digestible energy intake and body weight in growing-finishing pigs using three fitting models: linear mixed-effects (LME), Bayesian ridge regression (BRR) and random forest regression (RFR) models. After analysis, LME is the optimized dynamic model. To verify its validity, we selected 16 healthy Duroc × Landrace × Yorkshire crossbred castrated male pigs with an average initial body weight of about 85 kg and randomly assigned them to two groups. The Con group was allowed ad libitum feeding, while the Meta group used the LME model to restrict feeding. After 42 days, the growth performance between the two groups were no significant difference. The Meta group exhibited significantly lower feed-to-gain and average daily feed intake (P < 0.05), serum low-density lipoprotein cholesterol and aspartate aminotransferase levels (P < 0.05), and an increased abundance of beneficial gut microbial communities. The LME model, a precise and dynamic feeding formula derived from meta-analysis, effectively curbs feed intake while enhancing nutrient utilization and feed efficiency. It also mitigates environmental pollution and positively modulates gut microbiota composition.

This study evaluated long-term effects of replacing corn and soybean meal with wheat, broken rice, rice bran meal, rapeseed meal, and fermented distillers’ grains in gestating sow diets on offspring growing-finishing pigs’ growth performance, carcass traits, meat quality, and colonic microbiota. Thirty sows were assigned to corn-soybean meal (CON), unconventional ingredient (UCD), or unconventional low-protein diet (LP-UCD, 2 percentage points lower in CP). After weaning, 90 piglets (30 per group) were randomly allocated to pens (3 piglets/pen, 10 pens/group) and raised to approximately 120 kg body weight; growth data were recorded with pen as the experimental unit. At slaughter, 21 pigs (7/group) were sampled. Neither UCD nor LP-UCD affected overall growth performance, carcass traits, or meat quality of offspring. Compared to UCD, LP-UCD showed a lower feed-to-gain ratio at 8–25 kg (P < 0.05) but reduced average daily feed intake at 25–50 kg (P < 0.05). UCD had lower serum urea than CON (P < 0.05). LP-UCD had lower total protein, alanine aminotransferase, creatinine, and higher alkaline phosphatase, total cholesterol, and triglycerides than UCD (P < 0.05). LP-UCD tended to upregulate lipid metabolism genes like peroxisome proliferator-activated receptor delta. Colonic microbiota alpha/beta diversity did not differ. UCD increased the Firmicutes/Bacteroidota ratio vs. CON (P < 0.05). LP-UCD had higher Streptococcus and Coprococcus, and lower Anaerovibrio and Phascolarctobacterium vs. UCD (P < 0.05). In conclusion, gestational unconventional diets did not impair offspring growth or meat quality but were associated with alterations in metabolism, lipid-related gene expression, and microbiota composition. Notably, the unconventional low-protein diet showed potential to improve early feed efficiency.

Zinc is an essential trace element critical for animal growth, immune function, and antioxidant defense. Organic zinc sources chelated with amino acids are increasingly used as alternatives to inorganic zinc due to their potentially higher bioavailability. This study compared intracellular accumulation and transcellular transport of inorganic zinc sulfate (ZnS) and three organic zinc sources: zinc hydroxymethionine (ZnM), zinc valine, and zinc glycine (ZnG) in the porcine intestinal epithelial IPEC-J2 cell model, with particular emphasis on the effects of high-calcium levels. Results showed that ZnM and ZnG exhibited significantly greater intracellular zinc accumulation at 50–100 μM and higher transcellular transport efficiency than ZnS (P < 0.05), with ZnG displaying the highest transport rate (P < 0.05). High calcium (2400 μM) promoted apical zinc uptake and intracellular retention across all sources but inhibited early basolateral efflux; organic sources were less affected overall. Transcriptome analysis revealed 300 differentially expressed genes uniquely shared by ZnM and ZnG, enriched in riboflavin metabolism, fatty acid metabolism, taurine metabolism, and tight junction pathways. Under high calcium, organic zinc-specific pathways included sulfur metabolism and thyroid hormone signaling, whereas calcium broadly activated MAPK signaling and endoplasmic reticulum protein processing. These findings indicate that selected organic zinc sources offer superior transport efficiency and reduced susceptibility to high-calcium interference, likely through differential metabolic and transporter regulation.