Search Results (384)

Fat deposition in laying hens involves lipid synthesis, transport, storage, and allocation across multiple tissues, yet the metabolic links between abdominal fat (AF) and egg yolk (EY) lipid deposition remain unclear. Here, we integrated whole-genome resequencing data with untargeted metabolomic profiles from the liver, duodenum, ileum, cecum, and serum of 248 purebred Rhode Island Red hens at 100 weeks of age. We estimated metabolite-explained variance (me²) for 22 fat deposition-related traits, evaluated metabolite heritability, and combined Spearman correlation analysis with bidirectional generalized summary-data-based Mendelian randomization (GSMR) to identify shared metabolites and pathways associated with AF and EY traits. The me² showed clear tissue specificity, with the liver, serum, and duodenum showing significant explanatory signals for 77.3% (17/22), 72.7% (16/22), and 68.2% (15/22) of fat-related traits. Liver-, AF-, and body weight-related traits showed stronger metabolomic explanatory signals, with significant proportions of 71.4–100.0%, 28.6–100.0%, and 100.0% across tissues, respectively, whereas EY-related traits showed more restricted and tissue-specific associations (0–33.3%). Correlation analysis identified liver-enriched AF–EY shared metabolites (e.g., NADPH, cholesteryl sulfate, N6,N6,N6-trimethyllysine), most of which showed opposite association patterns between AF- and EY-related traits. Bidirectional GSMR prioritized 20 candidate metabolites with opposite putative effects on AF and EY traits, including CDP-choline, phosphorylcholine, and allantoin. Pathway integration highlighted fructose/mannose metabolism, glycerophospholipid metabolism, ABC transporters, folate/one-carbon metabolism, amino acid metabolism, and energy metabolism as core components of the AF–EY shared network. These findings reveal tissue-specific and shared metabolic bases of fat deposition and identify candidate metabolic signatures associated with lipid partitioning between abdominal fat and egg yolk in laying hens. Full article

Neolissochilus heterostomus, a cyprinid fish endemic to Yunnan Province, China, is highly valued for both ornamental and edible purposes, yet its wild populations are currently declining and classified as endangered. In this study, we present a chromosome-level genome assembly of N. heterostomus, utilizing the PacBio HiFi and Hi-C strategies. The assembled genome spans 1793.99 Mb and is anchored to 50 chromosomes, comprising a total of 50,203 genes. Genomic features and chromosomal karyotype data recorded in the present study are consistent with an allotetraploid origin for N. heterostomus. Comparative genomics shows that N. heterostomus shares a close phylogenetic relationship with another allotetraploid fish, the common carp Cyprinus carpio. In total, 4687 expanded and 1365 contracted gene families were identified in N. heterostomus. Further enrichment analyses indicated an overrepresentation of metabolism-related pathways among the expanded and positively selected gene families, whereas the contracted gene families were enriched in reproduction- and embryonic development-related pathways. Reproductive observations further indicate that N. heterostomus produces fewer eggs than other cyprinid species characterized by relatively long embryonic development periods (106.1 h; accumulated temperature: 2260.6 °C·h), including common carp, goldfish (Carassius auratus), grass carp (Ctenopharyngodon idella), pond loach (Misgurnus anguillicaudatus), and blunt snout bream (Megalobrama amblycephala). These findings suggest a potential association between metabolism-related genomic features and reproductive traits, although functional validation remains necessary. Overall, this study may offer insights into the polyploidization, metabolic, and reproductive traits of N. heterostomus, thereby providing genomic and biological resources that may support future studies relevant to the conservation and management of this endangered species. Full article

Among the ten local breeds of the Veneto region in Italy, Pepoi (PP) and Ermellinata di Rovigo (ER) hens start laying eggs earlier than the others. The egg laying rate (27–34 weeks of age) is higher (p < 0.01) in PP than in ER hens. Egg quality (at 33 weeks of age, 120 eggs/breed) was studied in fresh 1 day-old eggs and in preserved 21 day-old eggs according to breed and storage temperature (12 and 21 °C). Fresh ER eggs showed higher (p < 0.01) egg weights, yolk pH, Haugh units and yolk indices and lower (p < 0.01) eggshell lightness and thickness, surface area-to-volume ratios, and albumen pH than PP eggs, but the yolk-to-albumen ratio was similar between the breeds. After 21 days of storage, the egg traits showed the same trend for significant differences between breeds, with the exception of albumen pH and Haugh units, which were similar. Eggs stored at 21 °C showed lower (p < 0.01) Haugh units and yolk index values and higher (p < 0.01) albumen and yolk pH, albumen yellowness, and weight loss than eggs stored at 12 °C. Stored PP and ER eggs also differed in terms of observed changes in Haugh units, yolk pH and yolk index values with storage temperature: ER eggs showed higher (p < 0.01) yolk index values than PP eggs at both storage temperatures. Eleven weeks after the onset of laying, significant differences were observed in several traits of fresh and stored eggs from the studied breeds, particularly regarding the strength of the vitelline membrane. These preliminary results contribute to the characterization of the storage suitability of eggs from local breeds and to future crossbreeding programmes for enhancing chicken biodiversity. Full article

Apis cerana (A. cerana) is a native and widely managed honey bee species in China. Body size and body weight are crucial breeding traits, as colonies possessing individuals with large body weight tend to be healthier and exhibit high productivity. This study aimed to clarify the relationships between body size and body weight in A. cerana and to evaluate their associations with geographic, climatic, and colony productive traits for selective breeding. Body size and body weight were measured in virgin queens, drones, and workers from Jinfo Mountain, Chongqing, and additional measurements of queens and drones were implemented in five other regions across China. Linear mixed-effects models confirmed that body size had a significant positive effect on body weight in virgin queens, drones, and workers. However, correlations of body-size and body-weight traits among different bee groups were weak and non-significant after FDR correction, indicating that drones or workers cannot be used as direct substitutes for queen body-size traits in the present dataset. Standardized model estimates showed that queen and drone body-size and body-weight traits were consistently negatively associated with annual minimum and annual mean temperatures, but positively associated with latitude after FDR adjustment. Annual precipitation was also negatively associated with queens’ body size, queens’ body weight, and drones’ body size, whereas annual maximum temperature, longitude, and elevation showed no significant associations after FDR adjustment. Moreover, queens’ body size and body weight were significantly positively associated with honey yield, honey yield during the main nectar flow, and colony gentleness after FDR correction, whereas their associations with the number of effective eggs laid by queens, colony strength, and robbery were not significant after FDR correction. These findings suggest that queen body-type traits may serve as useful auxiliary indicators for selecting colonies with higher honey production and gentler behavior, but their relationships with other colony traits should be interpreted cautiously. This research is beneficial for initiating a body size-weight selective breeding program for A. cerana, as it can help optimize breeding objectives and accelerate genetic progress. Full article

Egg production in Gallus gallus domesticus represents a complex, economically critical trait shaped by multiple interrelated phenotypes, including age at first egg, total egg number, egg weight, and clutch characteristics. These traits are governed by polygenic inheritance and modulated by environmental factors, making the dissection of their genetic architecture essential for improving breeding efficiency, particularly under the emerging “long-life layers” production model. This systematic review aimed to integrate current knowledge on the genetic and molecular basis of egg production traits through analysis of genome-wide association studies and related genomic approaches. A structured literature search identified 27 eligible studies, which were evaluated following PRISMA guidelines. Data extraction and meta-analysis were conducted using standardized genome annotations and computational pipelines. The synthesis of available evidence demonstrates moderate to high heritability for key reproductive traits and highlights consistent genomic signals across multiple chromosomes. Importantly, the findings reveal a shift toward a systems-level understanding of egg production, involving conserved biological pathways related to neuroendocrine regulation, folliculogenesis, and energy metabolism. The integration of diverse genomic approaches enables the development of more precise, breed-specific selection strategies. Overall, these advances support a transition from traditional selection toward molecularly informed breeding frameworks, with significant implications for productivity, sustainability, and global food security. Full article

In recent decades, conservation of local poultry breeds has gained relevance to preserve genetic resources adapted to low-input systems and to enhance their valorization. This study addresses a key knowledge gap by providing a comprehensive characterization of the endangered Murciana chicken breed, native to southeastern Spain. We jointly evaluate recent population dynamics, conservation framework, morphology and morphometrics, growth patterns, and reproductive and productive traits. Data includes census and pedigree records, standardized morphological assessments, growth modeling, and production data from the conservation nucleus. The population increased from fewer than 150 registered animals in 2017 to more than 550 in 2024, indicating stabilization. The breed showed characteristics of slow-growing dual-purpose Mediterranean genotypes, with marked sexual dimorphism, Gompertz relative growth rates of 0.020 d⁻¹ (males) and 0.023 d⁻¹ (females), and adult weights of 3.2 kg and 2.4 kg, respectively. Carcass yield was moderate (61.9%), with higher leg (36.7%) than breast proportion (16.9%). Reproductive (fertility 88.6%, hatchability 80.6%) and laying performance (116.6 eggs/hen/year) were consistent with local extensive systems. These results provide a robust baseline to support conservation, genetic management, and sustainable use of the Murciana chicken breed, contributing to its long-term preservation and valorization. Full article

Bean weevil, Acanthoscelides obtectus, is a major post-harvest pest causing substantial losses in Phaseolus species worldwide. Identifying genetic resources with reduced susceptibility offers a sustainable alternative to chemical control. In this study, four Phaseolus coccineus and nine Phaseolus vulgaris landraces, along with one commercial cultivar, were evaluated under laboratory conditions using a free-choice test. Resistance-related traits, including oviposition (eggs per seed), adult emergence (holes per seed), damage incidence, and seed weight loss, were assessed across three replications. Significant genotypic variation was observed for all traits. Several P. vulgaris landraces (APN 42, APN 51, Yar) and one P. coccineus landrace (APN 85) showed no detectable seed damage or seed weight loss under free-choice conditions, whereas the susceptible check exhibited high infestation levels and up to 39.3% seed weight loss. Principal component analysis further distinguished low-damage genotypes from susceptible landraces, with resistance-associated traits contributing strongly to variation. These findings indicate that certain landraces exhibit reduced susceptibility to, or non-preference for, the bean weevil and may serve as valuable genetic resources for sustainable pest management. Full article

Muscovy ducks (Cairina moschata) exhibit strong nesting tendencies, which result in reduced egg-laying performance. The research team previously identified differential expression of the Ras homolog family member B (RHOB) gene in the ovaries of Muscovy duck during the nesting and laying periods through RNA-seq and quantitative real-time polymerase chain reaction (qPCR) analysis. This finding suggested that RHOB may be associated with nesting behavior in Muscovy ducks. Previous studies have demonstrated that the nesting behavior of Muscovy ducks is closely associated with the proliferation and apoptosis of their ovarian granulosa cells. It is speculated that RHOB may be involved in the proliferation and apoptosis of Muscovy duck ovarian granulosa cells. This study employed qPCR, immunofluorescence staining, live-cell Caspase3 activity and mitochondrial membrane potential assays, reactive oxygen species (ROS) staining, 5-Ethynyl-2′-deoxyuridine (EdU) staining, cell cycle analysis, cell apoptosis detection and cell counting kit-8 (CCK-8) assays. Our results showed that RHOB inhibited granulosa cell apoptosis and promoted granulosa cell proliferation. Similarly, in a granulosa cell apoptosis model, RHOB was also found to inhibit apoptosis in Muscovy duck granulosa cells. Further studies revealed that RHOB regulates mitochondrial function in granulosa cells. The combined experimental results indicate that RHOB regulates granulosa cell apoptosis in Muscovy duck follicles via the mitochondrial apoptosis pathway. These findings provide an experimental basis and theoretical foundation for the selective breeding of desirable traits in Muscovy ducks, such as low nesting behavior and high egg production. Full article

This study evaluated variations in phenotypic and physiological traits of Snowy White chickens reared under high-altitude conditions in Lhasa, China, at 3650 m and low-altitude conditions in Ya’an, China, at 600 m. Chickens reared at high altitude showed delayed sexual maturity and peak laying, as well as lower laying rate and hatchability. In contrast, egg weight at first laying was higher in chickens reared at high altitude. Organ index analysis showed that high-altitude chickens had a higher heart index but lower liver, stomach, and spleen indices than low-altitude chickens (p < 0.05). High-altitude chickens also had greater chest depth and chest circumference but shorter shank length and smaller shank circumference (p < 0.05). Multivariate analyses further indicated liver and spleen indices as major contributors to the separation between altitude groups. These results show that high-altitude rearing is associated with altered reproductive performance, organ development, and body conformation in Snowy White chickens. These findings may inform the evaluation, breeding, and management of layer chickens in plateau production systems. Full article

High-density SNP chips have been demonstrated to be effective instruments for simultaneously genotyping large numbers of loci, thereby facilitating genome-scale analyses and advancing genomic selection (GS) in poultry and livestock. The meat-type duck, an economically valuable poultry species in China, has so far lacked precise and high-throughput genotyping systems, which has constrained the broader implementation of GS and genome-wide association analyses (GWASs) and consequently slowed genetic progress. In this study, we developed and validated a novel SNP array based on Genotyping-by-Targeted-Sequencing (GBTS) technology. The array comprises 40,875 SNP markers evenly distributed across 32 duck chromosomes. Using data generated from this array, genomic heritability estimates were obtained for six economic traits in a cultured duck population (n = 400), with values of 0.61 ± 0.09, 0.69 ± 0.08, 0.80 ± 0.08, 0.11 ± 0.09, 0.14 ± 0.08, 0.31 ± 0.09 for age at first egg (AFE), egg production number at 38 weeks (EN38w), egg weight at 38 weeks (EW38w), body weight at 35 days (BW35d), shank length at 35 days (SL35d) and thickness of breast muscle at 40 days (TB40d). A total of 163 significant SNPs associated with economic traits were identified through GWAS, and annotation revealed 28 candidate genes related to five of these traits. Moreover, the prediction accuracy of ssGBLUP for AFE, EN38w, EW38w, BW35d, SL35d, and TB40d reached 0.55 ± 0.16, 0.56 ± 0.12, 0.57 ± 0.08, 0.25 ± 0.19, 0.31 ± 0.19, and 0.47 ± 0.17, respectively—values that exceeded those obtained using BLUP. Population genomic analyses of 400 ducks demonstrated that this SNP array provides improved genomic prediction accuracy over pedigree-based BLUP for most analyzed traits. Overall, the developed SNP array provides a robust, high-efficiency, and cost-effective genotyping platform that will accelerate genetic progress and promote the sustainable development of the meat-type duck industry. Full article

Heat stress is a major constraint to productivity and physiological homeostasis in laying hens. This study investigated integrated responses to acute heat stress using a multi-omics approach, including performance traits, serum biochemical parameters, histology, hepatic transcriptomics, cecal metagenomics, and metabolomics. Acute heat stress impaired productive performance, as reflected by changes in egg production and reduced eggshell strength, and induced systemic physiological disturbances, including increased stress- and injury-related blood indicators and disrupted metabolic and electrolyte balance. Histological analysis confirmed liver and intestinal tissue damage. Hepatic transcriptomics revealed inflammatory activation and suppression of metabolic pathways, particularly those involved in lipid metabolism, energy production, and redox homeostasis. Cecal metagenomic and metabolomic analyses showed altered microbial composition and functional potential, along with disruptions in amino acid, lipid, and energy metabolism. Collectively, these findings suggest that acute heat stress is associated with coordinated inflammatory responses and metabolic reprogramming, together with liver and intestinal injury and gut microbiota–metabolite alterations. The study provides a framework for understanding early heat stress responses and highlights potential targets for nutritional and microbiota-based interventions in poultry production. Importantly, serum biochemical indicators such as D-lactic acid and aspartate aminotransferase may serve as potential early biomarkers for monitoring heat-stress-induced physiological disturbances. Full article

The population of the blue crab Callinectes sapidus is rapidly expanding in the Mediterranean Sea, where it is causing increasing ecological and economic impacts. However, biological information from recently colonised areas remains limited. This study combined controlled experiments and reproductive analyses to investigate the key biological traits of C. sapidus in the northern Adriatic Sea. Feeding trials were conducted under controlled conditions to assess prey consumption and feeding behaviours using Manila clams (Ruditapes philippinarum) and Mediterranean mussels (Mytilus galloprovincialis), offered as monospecific and mixed diets. The results showed that, while the number of prey items consumed did not differ markedly between species, mussels provided a significantly higher edible biomass, indicating greater energetic profitability. Handling and consumption times were comparable between prey types, suggesting compensatory differences between opening and feeding phases. Food intake was strongly influenced by temperature, with peak consumption observed between 25 and 28 °C and reduced feeding at both lower and higher temperatures. Reproductive analysis of ovigerous females revealed high fecundity, with a mean of 1.63 ± 0.53 million eggs per individual and a positive relationship between fecundity and body size. Overall, the results confirm that C. sapidus combines trophic flexibility with high reproductive output—traits that support its invasive success. These findings improve the understanding of the blue crab’s ecological role in the northern Adriatic, providing useful insights for assessing its impact on shellfish aquaculture and developing management strategies. Full article

This study evaluated the effects of dietary crude glycerol supplementation on laying performance, egg quality traits, and egg yolk fatty acid composition in laying hens. A systematic search of peer-reviewed literature from major scientific databases identified thirteen eligible studies. Effect sizes were calculated as mean differences using random-effects models, and subgroup and meta-regression analyses were conducted to assess the influence of inclusion level, hen age, strain, and dose–response relationships. Moderate inclusion of crude glycerol (≤4%) significantly increased egg production (MD = +0.71 percentage points; p = 0.019) and egg mass (MD = +1.08 g; p = 0.007). External egg quality traits, including shell thickness, shell breaking strength, and shell percentage, were not significantly affected, while albumen height decreased slightly (MD = −0.14 mm; p = 0.004) and Haugh unit remained unchanged. Crude glycerol supplementation also increased linoleic acid, total unsaturated fatty acids, and total polyunsaturated fatty acids (p < 0.001). Responses varied with inclusion level, hen age, and strain, and a positive dose–response relationship between crude glycerol level and yolk linoleic acid was observed in white-egg strains. Overall, moderate crude glycerol inclusion can partially replace conventional dietary energy sources with minimal adverse effects on egg quality. Full article

Clutch persistence, defined as the ability to sustain consecutive egg-laying cycles, is a pivotal determinant of profitability in the poultry industry, particularly for aging laying hens (≥65 weeks). However, the molecular mechanisms governing this trait remain elusive, largely due to the traditional “ovary-centric” paradigm that overlooks systemic regulation by the gut microbiota. To address this knowledge gap, the present study aimed to dissect the comprehensive regulatory network governing clutch persistence using integrated multi-omics analyses. A total of 20 sixty-five-week-old Rhode Island Red (RIR) laying hens with cumulative egg production exceeding 300 eggs but distinct clutch persistence were stratified into a high-clutch persistence group (HCP, ≥25 clutches, n = 10) and a low-clutch persistence group (LCPLCP, ≤15 clutches, n = 10). Multi-omics profiling, including ovarian transcriptomics, proteomics, and metabolomics; serum metabolomics; and cecal microbiota 16S rRNA sequencing was performed. Data integration and association mining were conducted via Spearman correlation analysis with stringent thresholds (r > 0.6, p < 0.01). Integrated analyses revealed a “gut–ovary axis” regulatory model mediated by a lipid mediator network, operating through a three-tiered mechanism: (1) Gut Initiation: The HCP group exhibited enriched cecal γ-Proteobacteria, which promoted biosynthesis of lipid precursors. (2) Serum Transport: Key serum lipid mediators, most notably LysoPC (22:6) (VIP = 4.5) and cholesterol ester CE (20:4), served as critical carriers transducing gut-derived signals to the ovary. (3) Ovarian Execution: These lipid signals activated a core ovarian metabolic pathway centered on the PLA2G6-ALOX15B-AGPAT3 axis, which coordinated follicular development and ovulation by supplying steroid hormone synthesis substrates, exerting anti-inflammatory effects, and stabilizing membrane structures. Collectively, this study demonstrates that gut microbiota modulates clutch persistence in aging laying hens via lipid mediators, orchestrating a systemic “gut–serum–ovary” regulatory cascade. These findings provide a novel molecular framework for extending the economic egg-laying cycle through the targeted manipulation of intestinal microbiota or serum lipid metabolism. Full article

Ooencyrtus kuvanae is an egg parasitoid species that attacks the egg masses of Dendrolimus spp. and Lymantria spp. in China, which gives it a temporal niche advantage against pest infestations by Dendrolimus spp. and Lymantria spp. Moreover, it has a short life cycle, high offspring outcome, and female-biased population, showing distinctive ovarian development and oviposition behaviors and thus providing an ideal model for reproductivity and regulatory mechanisms. Previous studies have found that the Vitellogenin (Vg) and Vitellogenin Receptor (VgR) genes play important regulatory roles in the ovarian development of a few wasp species, but little is known about how these two genes work within O. kuvanae. Therefore, we observed their oviposition traits, characterized their gene structure, and clarified the function of Vg and VgR. The results showed that continuous daily oviposition significantly reduced the daily mature eggs and offspring per female by providing a single host egg for oviposition in each experimental trial, while the proportion of female offspring reached 100%, indicating that thelytokous parthenogenesis occurred. The full-length sequences of OkVg and OkVgR were cloned and submitted to GenBank. qPCR detection revealed that the transcription levels were the highest in adults. Feeding 20-hydroxyecdysone can increase OkVg gene expression (by 2.4-fold), while feeding juvenile hormone can promote their OkVgR expression (by 2.3-fold). RNA interference significantly downregulated OkVg and OkVgR expression in adult ovaries. And dsVg significantly reduced the ovarian egg load by 45% (p < 0.05), while dsVgR caused oviduct contraction and offspring decrease. Simultaneous silencing of OkVg and OkVgR significantly reduced offspring outcomes, indicating both genes may jointly dominate oocyte development. This study provides functional evidence of molecular regulation and interaction between OkVg and its receptor genes. Full article