Search Results (1,477)

Fertility traits are core functional traits in dairy cattle, yet their low heritability makes traditional phenotypic selection inefficient. Weighted single-step GWAS (WssGWAS) improves detection power by integrating pedigree, phenotype, and genotype data. This study aimed to estimate genetic parameters and identify genomic regions associated with eight fertility traits in Chinese Holstein cattle using pedigree, phenotype, and genotype data. Genetic parameters were estimated via pedigree-based BLUP (PBLUP) and ssGBLUP, and a WssGWAS was performed to detect QTL. A total of 23,771 cattle were genotyped using liquid-phase chips and 150 K chips; after imputation and quality control, 13,690 individuals and 103,262 SNPs were retained. The eight traits comprised heifer traits (AFS, AFC, NS_H, and IFL_H) and cow traits (ICF, CI, NS_C, and IFL_C). The findings indicate that while most fertility traits exhibit low heritability (ranging from 0.024 to 0.085), AFS displays high heritability (0.390). WssGWAS identified 162 QTL intervals and 645 candidate genes, including OVOS2, PMEPA1, TEPP, and the RAG family, which are closely associated with reproductive function. These findings provide a foundation for future research into the genetic mechanisms of fertility and support improved genomic predictions in Chinese Holstein cattle. Full article

High temperatures accelerate bolting and shorten the vegetative phase, thereby reducing the marketable yield in lettuce(Lactuca sativa L.). Using the KNOU lettuce core collection (KLC; n = 288), which represents major horticultural types, we integrated genome-wide association studies (GWAS) with genotyping-by-target-sequencing (GBTS), a multiplex target amplicon sequencing approach, to develop compact SNP marker panels for breeding-relevant prediction of reproductive timing. The KLC was genotyped via genotyping-by-sequencing (GBS; 97,528 SNPs) and phenotyped across two spring-to-summer seasons to analyze cumulative temperature to bolting (CTTB) and cumulative temperature to anthesis (CTTA) under protected cultivation conditions, revealing broad variation and high heritability (H = 0.79 and 0.74, respectively). Multi-model GWAS consistently identified a major hotspot on chromosome 7 for both traits, whereas additional loci showed trait- and year-specific effects. A lead SNP on chromosome 7 was validated by KASP, confirming a consistent allelic effect across genetic backgrounds. GWAS-supported loci were converted into compact GBTS panels (CTTB-only, CTTA-only, and pooled), and their ability to predict genomic estimated breeding values (GEBVs) was evaluated via repeated 5-fold cross-validation. The pooled panel achieved the highest predictive performance for CTTB (up to R² = 0.41 with random forest and R² = 0.37 with RR-BLUP), outperforming the CTTB-only panel. In contrast, CTTA prediction was more moderate (up to R² = 0.32). Overall, this GWAS-to-GBTS panel strategy provides a practical basis for low-cost, early selection of reproductive timing in lettuce breeding. 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

Sex control technology has become a key technique in aquatic animal breeding, as many aquatic species exhibit distinct sexual dimorphism in growth, reproduction, immunity, and other economically important traits. Therefore, methods such as regulating sex ratios and establishing unisexual populations can significantly enhance aquaculture productivity and breeding efficiency. Recent years have seen a rapid advancement in the field of research on the mechanisms of sex determination and differentiation in aquatic animals, as well as sex control technologies. This review summarizes the latest advances in research on the mechanisms of sex formation in aquatic animals, including genetic sex determination, environmental sex determination, and genotype-environment interactions. Furthermore, this review outlines the major sex-linked genes and molecular markers used for genetic sex identification, introduces key male and female regulatory factors involved in gonadal differentiation, and explores the application of major sex control methods in aquaculture breeding, including techniques such as interspecific hybridization, environmental regulation, hormone induction, parthenogenesis, and gene editing. Full article

Progesterone (P4) exerts important vascular and immunomodulatory effects that influence platelet (PLT) activation and serotonin (5-HT) handling across mammalian species; nevertheless, its role in modulating PLT physiology during diestrus in mares remains poorly defined. This study hypothesized that physiological variations in luteal activity during diestrus are associated with changes in PLT activation and 5-HT-related parameters. The first objective was to determine whether changes in circulating P4 during diestrus are associated with alterations in PLT aggregation, circulating 5-HT, and PLT morphological indices in healthy mares; the second objective was to identify a diestrus day providing consistent physiological conditions for assessing PLT-related biomarkers. Twenty clinically healthy Spanish Purebred mares aged 4–9 years old were monitored. Blood samples were collected on days 5, 14, and 16 post-ovulation, with luteal status confirmed by ultrasonography. P4 concentrations were determined using a solid-phase I-125 radioimmunoassay (RIA), 5-HT concentrations were quantified using a competitive enzyme immunoassay, and PLT indices were measured using an ADVIA 2120i hematology analyzer. Data were compared using appropriate parametric or non-parametric tests after assessing distribution, and correlations were analyzed using rank-based correlation analysis, using Pearson or Spearman coefficients according to variable distribution. P4 concentrations were higher on days 14 and 16 compared with day 5 (p < 0.05), with no significant differences between days 14 and 16. Platelet aggregates (AGREG) showed the greatest variation, with significantly higher values on day 14 compared with day 5 (p < 0.05). In contrast, circulating 5-HT and all PLT morphological indices (PLT count, PCT, MPV, PLCR, PDW, PCDW, MPM, and PMDW) remained unchanged across diestrus. PLT aggregation showed a strong positive association with circulating P4 concentrations (r = 0.88, p < 0.05), whereas no meaningful correlations were observed between 5-HT and AGREG or between 5-HT and PLT morphological parameters. Internal correlations among PLT indices followed expected biological patterns, confirming the stability of structural PLT traits over short physiological intervals. These findings demonstrate that during diestrus, PLT activation—but not PLT morphology or circulating 5-HT—varies in parallel with P4 in mares. Day 14, corresponding to mid-diestrus, characterized by high luteal activity, represents an informative time point for assessing PLT activation and related biomarkers, providing a framework for standardizing sampling protocols for PLT-derived products in equine reproductive medicine. Full article

As a dual-purpose (meat and fat) coarse-wool sheep breed in Xinjiang, the Pishan Red sheep exhibits year-round estrus and excellent reproductive performance. The aim of this study was to systematically estimate the genetic parameters of growth traits in Pishan Red sheep at each stage from 0 to 12 months of age, and to provide a scientific basis for optimizing early selection indices for this breed. Year of birth, type of birth, and sex were included as fixed effects, while maternal genetic effects and individual additive genetic effects were treated as random effects. A multi-trait animal model was constructed using DMU software to analyze the genetic parameters. The results showed that for growth traits at 0 months of age, heritability ranged from 0.09 to 0.64, genetic correlations from –0.03 to 0.84, and phenotypic correlations from 8.2 × 10⁻³ to 0.32. Among these, the direct heritability of body weight was 0.18, and the maternal heritability was 0.21, while cannon circumference was identified as a high-heritability trait. At 2 months of age, heritability ranged from 0.04 to 0.69, genetic correlations from −0.78 to 0.96, and phenotypic correlations from 0.036 to 0.44. Body weight, body length, and cannon circumference were high-heritability traits. At 6 months of age, heritability ranged from 0.04 to 0.71, genetic correlations from −0.32 to 0.70, and phenotypic correlations from −0.13 to 0.54. Body weight was a medium-heritability trait, while chest width and cannon circumference were high-heritability traits. At 12 months of age, heritability ranged from 0.07 to 0.48, genetic correlations from −0.04 to 0.87, and phenotypic correlations from 0.28 to 0.72. Body weight was a medium-heritability trait, whereas body height, body length, cannon circumference, and heart girth were high-heritability traits. Both body weight and cannon circumference exhibited high heritability throughout the 0–12 month period and can therefore serve as key selection indices for early breeding in this breed. The findings of this study provide essential local baseline data for the genetic improvement, breeding program design, and genetic evaluation of Pishan Red sheep. Full article

Chinese Simmental cattle are a high-quality breed developed through long-term crossbreeding and selection after their introduction into China and have become the main dual-purpose cattle population in the Xinjiang region. To deeply dissect the population structure, characteristics of the population structure, and the genetic basis of the twinning trait, this study focused on Xinjiang Chinese Simmental cattle as the main research subject. It integrated genomic data from global public databases to systematically conduct population structure analysis, genetic relationship analysis, and genome-wide selection signature analysis. Population genetic analysis revealed that the IBS matrix and G matrix indicated that some individuals from different geographical origins exhibited distant genetic relationships; the Xinjiang population showed the fastest LD decay, suggesting abundant genetic diversity; the inbreeding coefficient based on Runs of Homozygosity (ROH) across populations ranged from 0.036 to 0.063; principal component analysis and phylogenetic tree showed that some individuals from different geographical origins had certain genetic interconnections; admixture analysis indicated that K = 5 was the optimal model, with each population exhibiting clear genetic differentiation and admixture characteristics. Furthermore, by combining F_st and θπ analysis (comparing the Xinjiang population with other geographical populations), a total of 89 candidate genes associated with the twinning trait in Xinjiang Chinese Simmental cattle were screened, including CYP19A1, HORMAD1, GRB14, CADM2, CXCR4, and others that have been reported to be closely related to oogenesis and reproductive function. In summary, this study explores genome-wide genetic differences among Simmental cattle populations from different regions, deepens our understanding of their population structures, and offers new candidate genes and molecular markers for high-fecundity breeding in Simmental cattle. Full article

Biological invasions are among the main threats to freshwater biodiversity, yet ecological patterns associated with assemblage structure and high relative abundances of non-native fishes in spring ecosystems remain insufficiently documented. We evaluated seasonal variation in community composition, reproductive traits, and trophic interactions in La Zarcita springs, part of the Natural Protected Area Laguna de Zacapu, central Mexico. Bimonthly sampling was conducted, including stomach content analysis and reproductive trait assessment. A total of 14 fish taxa were recorded (seven native and seven non-native), with the assemblage numerically dominated by Oreochromis niloticus (30%), Pseudoxiphophorus bimaculatus (24%), and Xiphophorus hellerii (14%). Overall diet composition did not differ significantly between taxa classified as native and non-native (PERMANOVA, p > 0.05), consistent with overlap in resource use within the assemblage. Exploratory assemblage-level analyses detected differences in omnivory index values among taxa grouped according to species origin (LMM, p < 0.05). Reproductive analyses detected variation in fertility values (GLMM, p < 0.05), reproductive activity (Wilcoxon test, p < 0.05), gonadosomatic index values, and Fulton’s condition factor values (LMM, p < 0.01) among taxa within the assemblage. Physicochemical variables varied seasonally but were not significantly associated with trophic composition, condition factor values, or reproductive traits in the statistical analyses performed. Overall, the results document variation in reproductive characteristics and trophic patterns among taxa within this urbanized spring system and highlight the value of assemblage-level ecological studies for understanding fish community structure in small freshwater habitats. Full article

Insect migration is an energetically costly process often involving a trade-off with reproduction. However, how adult nutritional stress regulates resource allocation between these two life-history traits remains unclear. Here, we compared morphological traits, flight performance, ovarian development, fecundity, and energy reserves between migrants and residents of Cnaphalocrocis medinalis under fed and starved conditions. Morphological analyses showed no significant differences in body weight, body length or forewing length between migrants and residents, regardless of nutritional status. Under starvation, migrants exhibited significantly greater flight distances and speeds than residents, and their flight distance and duration were also higher than those of fed migrants. Starved migrants showed a higher proportion of immature ovaries and higher fecundity, accompanied by a prolonged pre-oviposition period, indicating reproductive delay. Under fed conditions, ovarian development and fecundity were similar between migrants and residents. Energy reserve assays revealed that starved migrants accumulated more abdominal triglycerides but had lower thoracic glycogen than residents, suggesting preferentially triglyceride storage in the abdomen for long-distance flight. Under fed conditions, residents possessed higher thoracic glycogen levels than migrants, whereas no differences were observed in triglyceride levels. These results indicate that C. medinalis prioritizes energy allocation to migration over reproduction under energy shortage, but switches to a strategy that simultaneously meets the demands of both when nutrition is sufficient. Our findings underscore the role of adult nutrition in mediating the energy allocation between migration and reproduction, offering a scientific basis for the precise monitoring and management of this pest. Full article

Phytoestrogens are plant-derived phenolic compounds that structurally resemble endogenous estrogens and can exert both estrogenic and anti-estrogenic effects in animals. In ruminant nutrition, the main classes of phytoestrogens (isoflavones, lignans, stilbenes, coumestans and selected flavonoids) are supplied predominantly by legume forages and soybean-based feeds, in which concentrations can reach several mg/g of dry matter. After ingestion, these compounds are extensively metabolized by the rumen microbiota to derivatives with altered biological potency, such as equol and p-ethyl-phenol, which influence endocrine, immune and metabolic pathways. Experimental and field studies in cattle, sheep and goats indicate that dietary phytoestrogens may improve nitrogen utilization, immune competence, growth performance, antioxidant status and milk yield. However, they can also impair fertility, modify hormone profiles and compromise embryo survival in a compound-, dose-, and species-dependent manner. In this review, we summarize current knowledge on the botanical and nutritional sources, ruminal metabolism and transfer of phytoestrogens in ruminants, and critically examine their effects on blood metabolites, immune responses, growth and carcass traits and lactational performance and reproductive function. A structured literature search based on PRISMA principles was used to identify and appraise experimental and observational studies in both grazing and intensive production systems up to 2025. Remaining knowledge gaps and practical implications for the safe use of phytoestrogen-rich feeds in livestock production are highlighted. Full article

Duolang sheep, an indigenous breed of southern Xinjiang, are significant for their agricultural systems due to their adaptation to arid and semi-arid environments. This review integrates recent advancements in Duolang’s reproductive biology, genomic studies, and management strategies to address the breed’s reproductive efficiency under challenging ecological conditions. Reproductive traits such as puberty onset, estrous cycle characteristics, and seasonal breeding are influenced by complex genetic and several environmental factors. Numerous remarkable genomic findings highlight key loci related to fecundity, including the Booroola FecB mutation, as well as genes involved in steroidogenesis, folliculogenesis, and HPG axis regulation. Despite the genetic potential for increased prolificacy, Duolang sheep often exhibit low litter sizes, largely constrained by detrimental environmental factors and management practices. This review emphasizes the significance of integrating genetics, nutrition, and reproductive management to optimize productivity. Strategies such as nutritional flushing, hormone-based estrous synchronization, and selective breeding for increased litter size are discussed, with a focus on minimizing the risks associated with early puberty and lamb survival. Furthermore, the review explores the potential of genomic selection, marker-assisted breeding, and advanced reproductive technologies to enhance the breed’s performance. Finally, the review outlines future research directions, necessitating the development of genomic resources, precise breeding programs, and field trials on reproductive interventions to accelerate genetic gains in Duolang sheep. This integrated approach promises to improve reproductive outcomes, with implications for sustainable sheep production in Xinjiang and similar environments across the globe. Full article

Genetic resources of small ruminants are essential for food security in arid regions; however, basic data for each breed in Saudi Arabia remain incomplete. This study establishes a comprehensive national database through a systematic survey of 104 farms, covering 21,214 heads of livestock (sheep and goats) across the kingdom’s primary agro-ecological zones between January and October 2025. Although national census data indicate that major breeds of sheep such as Naeemi, Najdi, Arabi, and Harri or goats such as Ardi exceed the FAO’s numerical thresholds for “not at risk,” our analysis reveals a fundamental paradox of “genetic vulnerability,” defined as a high risk of inbreeding depression and genetic stagnation despite high census numbers. The results show significant regional variations in prolificacy (p < 0.05), with the southern region displaying a substantial productivity gap compared to the central and eastern regions, mainly due to reliance on traditional grazing (46.7%) and limited infrastructure. This vulnerability is driven by a high risk of systematic inbreeding, with 65.7% of breeders acquiring sires from their own herds, a situation worsened by a severe 80% shortage of high-quality breeding males in the central region. Furthermore, selection criteria heavily emphasize esthetic phenotypic traits (over 80%) rather than production indicators (less than 8%), hindering genetic progress. Correlation analysis showed that higher farmer education levels were negatively associated with reproductive challenges (r = −0.216), while high feed prices remained a near-universal obstacle (97.1%). To mitigate these risks, we recommend implementing region-specific sire exchange programs to break closed breeding loops and establishing a national performance recording system to shift selection focus from phenotypic traits to measurable productivity. This study provides a vital, evidence-based framework for transitioning toward data-driven, resilient conservation and breeding strategies. Full article

The Dwarf Ombú, Phytolacca tetramera, is a rare and highly unusual plant endemic to the northeastern Pampean grasslands of Argentina and is currently considered of high conservation priority. In order to better understand its biology, ecology, and conservation requirements, we studied its anatomy, reproductive traits, life history, and distribution based on field observations and herbarium material. Our results show that P. tetramera possesses a combination of traits consistent with the concept of ecological anachronism. The species produces large fleshy fruits whose size and shape are comparable to those interpreted as adapted for dispersal by extinct megafauna. In addition, the plant exhibits morphological and ecological adaptations associated with intense grazing, trampling, and drought tolerance, including robust underground structures and a growth pattern comparable to underground trees from seasonally dry open habitats. These findings suggest that P. tetramera evolved under ecological conditions markedly different from those existing today, including megafaunal disclimax environments that disappeared after the late Pleistocene extinctions. This ecological mismatch may help to explain its present rarity, fragmented distribution, and low population numbers. Our results also indicate that current conservation strategies for P. tetramera should consider the role of disturbance regimes and extinct ecological interactions in shaping the biology of this species. Full article

Economic traits in livestock and poultry arise from the intricate interplay between genetic inheritance and environmental factors, mediated largely by epigenetic regulation. Histone modifications, particularly methylation and acetylation, serve as fundamental epigenetic mechanisms that dynamically remodel chromatin architecture and regulate gene expression in response to developmental and environmental cues. By bridging the gap between static DNA sequences and complex phenotypes, these dynamic marks offer a novel perspective for elucidating trait formation. This review examines the regulatory roles of histone modifications in shaping key economic traits, focusing on skeletal muscle development, fat deposition, and reproductive performance. Furthermore, we highlight two prospective strategies for integrating histone modification data into modern breeding programs: utilizing comprehensive epigenomic maps as novel biomarkers for precision selection, and implementing targeted nutritional regimens to program early phenotypic development. Despite substantial mechanistic advances, critical challenges persist, including high detection costs, inherent tissue specificity, and the necessity to validate transgenerational stability. Looking forward, the integration of multi-omics approaches is anticipated to propel animal breeding beyond traditional genomic selection toward an era of precise epigenomic design. Full article

The buffalo is an important agricultural species due to its many productive characteristics, which encourage its use worldwide. Uncovering the processes of selective sweeps is critical for a comprehensive understanding of genomic mechanisms that influence phenotypic differentiation in buffalo. This study aims to refine signatures of selection in Bulgarian (BUL), Hungarian (HUN), and Romanian (ROM) buffalo breeds using runs of homozygosity (ROHs), the integrated haplotype score (iHS), the standardized log-ratio of the integrated site-specific extended haplotype homozygosity (EHH) between pairs of breeds test (Rsb), and cross-population EHH (XP-EHH) approaches. The SNP dataset of 160 genotypes from BUL, HUN, and ROM buffalo breeds was genotyped using the Axiom^® Buffalo Genotyping Array 90K from Affymetrix. By combining the ROH, iHS, Rsb, and XP-EHH methods, we identified many important genomic regions and candidate genes associated with milk production (SLC24A2, TMEM132C, and ALCAM), reproduction (CSMD1, NTS, PLIN2, GPC5, and FSHR), growth (MYOM2, CLN8, and RRAGA), immune response (METTL25, MLLT3, NAALADL2, and GAB2), and adaptation (ADAMTSL1) in BUL, HUN, and ROM buffalo breeds. Our findings highlighted selection signals and genes related to important economic traits in the BUL, HUN, and ROM buffalo breeds, providing promising candidate genes for further research and inclusion in conservation and selection plans for these breeds. Full article