Search Results (148)

Siniperca chuatsi is an important high-quality freshwater aquaculture species in China. In nature, it feeds exclusively on live food. In this study, domesticated juvenile S. chuatsi were divided into three groups and fed live food (group L), compound feed (group C), or a mixed diet (group M) for three months to investigate the molecular mechanisms underlying adaptation to compound feed. Histopathological examination revealed that compound feed consumption induced looser liver cell arrangement, hepatocyte morphological irregularities, and vacuolization. A total of 1033 and 1428 differentially expressed genes (DEGs), and 187 and 184 differential metabolites (DMs), were identified in the C vs. L and C vs. M groups, respectively. Transcriptomic analysis revealed that the significantly and commonly enriched metabolic pathways shared by both comparison groups were predominantly involved in amino acid, carbohydrate, and lipid metabolisms. Metabolomic analysis demonstrated that the significantly and commonly enriched metabolic pathways shared by both comparison groups were the arachidonic acid metabolism, linoleic acid metabolism, oxidative phosphorylation, and PPAR signalling pathways. Integrated omics analysis showed that the PPAR signalling pathway was the only significantly co-enriched pathway across both omics datasets. This study provides new insights into the molecular mechanisms of compound feed adaptation and provides theoretical support for selecting feed traits in S. chuatsi. Full article

Honeybees (Apis mellifera) are pollinators for most crops in nature and a core species for the production of bee products. 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. In this study, small interfering RNA (siRNA) targeting 15-Hydroxyprostaglandin dehydrogenase (15-PGDH) was incorporated into the feed for feeding worker bee larvae, thereby achieving the silencing of this gene’s expression. The research further analyzed the impact of the RNA expression level of the 15-PGDH gene on the juvenile hormone (JH) titer and its subsequent effects on the body weight and size of worker bees. The results show that inhibiting the expression of 15-PGDH in larvae could significantly increase JH titer, which in turn led to an increase in the body weight of worker bees (1.13-fold higher than that of the control group reared under normal conditions (CK group); p < 0.01; SE: 7.85) and a significant extension in femur (1.08-fold longer than that of the CK group; p < 0.01; SE: 0.18). This study confirms that 15-PGDH can serve as a molecular marker related to body weight and size in honey bees, providing an important basis for molecular marker-assisted selection in honey bee breeding. Full article

Background: The relationship between genetic diversity and fitness is well understood, but few studies have investigated how behavior influences genetic diversity, or vice versa. We investigated the relationship between feeding behavior (on a pelleted diet) and genetic diversity in pikeperch, a piscivorous species. Methods: A total of 135 juvenile pikeperch from the same stock were grouped into three behavioral groups: pellet consuming, pellet refusing, and cannibalistic. Eighteen microsatellite markers were used to characterize the genetic diversity and structure of individuals. Results: The juveniles were classified into two genetic clusters: one dominated by pellet-consuming individuals and the other by pellet-refusing individuals containing equal proportions of cannibal individuals. Three of the microsatellite markers were under selection, but only one showed significant genetic segregation between the groups. For this marker, the pellet consumption was associated with low fragment length. Individual multilocus heterozygosity was significantly higher in the pellet-refusing group. Conclusions: These results suggest that pellet consumption acts as an uncontrolled selective force during domestication, influencing the genetic variability of domesticated populations. The ability to habituate to pellets has a significant genetic basis. Cannibalism does not affect genetic variability, and the emergence of the trait is independent of the propensity to consume pellets. Full article

Silk yield enhancement in sericulture has plateaued. Sodium butyrate (NaB) is known to improve production performance in livestock and poultry, yet its effects on silkworm silk yield remain uncharacterized. Here, we evaluated the impact of dietary NaB supplementation on silkworm growth, silk gland development, and cocoon output. Mulberry leaves were immersed in NaB solutions at concentrations of 0, 2.5, 5, 10, 20, 40, or 80 mM, and subsequently provided as feed to third- to fifth-instar larvae. Among these, 10 mM NaB treatment most effectively promoted larval and pupal weight gain and increased food intake. Phenotypic and economic trait analyses revealed that 10 mM NaB treatment significantly enlarged the silk gland and boosted overall silk yield. Mechanistically, NaB enhanced body growth by increasing feeding intake and influencing the juvenile hormone and ecdysteroid signaling pathways; moreover, it promoted DNA replication in silk gland cells, thereby influencing silk gland development. Taken together, our findings demonstrate that dietary supplementation with an appropriate concentration of NaB concurrently enhances body growth and silk gland development, leading to higher silk production, and underscore the potential of short-chain fatty acid salts in advancing sericulture. Full article

This study investigates the effects of salinity, temperature, and diet on the biological characteristics of the rotifer Brachionus plicatilis, an essential live feed in aquaculture. The results indicate that environmental factors have a significant influence on reproductive traits and survival. At a salinity of 5 ppt, B. plicatilis achieved the highest fecundity (25.50 ± 0.58 inds.), while the longest lifespan (273.00 ± 72.52 h) was observed at 35 ppt. The temperature had a strong influence on developmental rates, with the shortest juvenile period recorded at 35 °C (8.00 ± 0.00 h) and the longest lifespan at 20 °C (270.62 ± 30.38 h). The diet also played a critical role, with Chlorella vulgaris supporting maximum fecundity, whereas mixed diets prolonged lifespan to 290.50 ± 62.83 (h). These findings provide valuable insights into optimizing rotifer culture systems to improve aquaculture productivity and sustainability. Full article

Background/Objectives: Epilepsy and sleep disturbances frequently co-occur, yet the causal nature of this relationship remains uncertain, particularly in relation to epilepsy subtypes and status epilepticus. We investigated potential bidirectional causal associations between sleep-related traits and epilepsy, including subtypes and status epilepticus, using Mendelian randomization (MR). Methods: We conducted two-sample MR using genome-wide association study (GWAS) summary statistics from European ancestry cohorts. Epilepsy, its subtypes, and status epilepticus were analyzed using data from the International League Against Epilepsy Consortium on Complex Epilepsies (ILAE) and the FinnGen study. Nine self-reported sleep-related traits were derived from the UK Biobank-based GWAS. Causal estimates were primarily obtained using inverse variance weighted models with additional MR analysis methods. Pleiotropy and heterogeneity were assessed to enhance the robustness of the finding. Results: Several subtype-specific associations were identified, with direction and statistical significance varying across cohorts and subtypes. After correction for multiple testing and filtering for tests with ≥10 instrumental variables to ensure robust and reliable MR estimates, several consistent and potentially mutually reinforcing associations emerged. In the ILAE cohort, focal epilepsy with hippocampal sclerosis was associated with an increased risk of insomnia, and juvenile myoclonic epilepsy with reduced sleep duration. In the FinnGen cohort, overall epilepsy was associated with increased risk of both insomnia and daytime sleepiness. In reverse MR, daytime sleepiness and napping were associated with increased risk of epilepsy, while daytime napping and frequent insomnia symptoms were linked to elevated risk of status epilepticus. Conclusions: Our findings reveal subtype-specific and bidirectional causal links between epilepsy and sleep-related traits. These results highlight the biological interplay between epileptic networks and sleep regulation and underscore the need for further clinical and mechanistic studies. Full article

Understanding how fish communities respond to long-term environmental changes in regulated floodplain ecosystems is essential for managing biodiversity amid increasing anthropogenic and climatic pressures. This study evaluates the spatiotemporal dynamics of functional diversity in juvenile fish assemblages within the Dnipro-Orilskiy Nature Reserve (Ukraine) from 1997 to 2015. By employing a combination of extensive ichthyological field surveys and satellite-derived environmental indices (including NDVI, chlorophyll-a, turbidity, and spectral proxies for algal blooms), we assessed the impacts of eutrophication, hydrological alterations, and climate warming on functional structure. Our results reveal three key responses in fish functional diversity: (1) a decline in functional specialization and imbalance, indicating the loss of unique ecological roles and increased redundancy; (2) a rise in functional divergence, reflecting a shift toward species with outlying trait combinations; and (3) a complex pattern in functional richness, with trends varying by site and trait structure. These shifts are linked to increasing eutrophication and warming, particularly in floodplain areas. Remote sensing effectively captured spatial variation in eutrophication-related water quality and proved to be a powerful tool for linking environmental change to fish community dynamics, not least in inaccessible areas. Full article

This study investigated the effects of feeding striped beakfish (Oplegnathus fasciatus) newly hatched larvae on the survival and growth of kawakawa (Euthynnus affinis) larvae and juveniles, as well as their relative growth patterns. Fertilized eggs of kawakawa were reared in 1 m³ experimental tanks until 13 days post-hatch (dph). From 3 to 8 dph, larvae were fed enriched rotifers, and from 9 to 12 dph, they were assigned to two experimental groups: one receiving only a formulated diet and the other receiving a combination of the formulated diet and 10,000 striped beakfish newly hatched larvae every day in each tank. The group fed newly hatched larvae exhibited approximately 36% greater growth than the group fed only the formulated diet. However, survival at 13 dph was approximately 34% lower, suggesting that further investigation is needed to determine the optimal feeding quantity of newly hatched larvae. The relative growth patterns of larvae and juveniles reared in a commercial 30 m³ tank showed morphological traits characteristic of scombrid fish, such as a longer preanal length and upper jaw length. Growth patterns varied at three key body lengths (notochord length or standard length; 3, 8–10, and 30 mm), as well as at their corresponding standard lengths. In kawakawa, the upper jaw exhibited early accelerated growth compared to other scombrid species. This characteristic is believed to facilitate the early onset of piscivory under captive conditions. Full article

Intraspecific variations in the morphological traits of juveniles and adults of the Brazilian silverside, Atherinella brasiliensis, from three estuarine habitats were studied to understanding whether their morphology interacts with their dietary composition and habitat structure. For each individual, fourteen morphological measurements and eight functional traits were recorded related to food acquisition and locomotion. The highest abundance of A. brasiliensis was recorded in mudflats, which were often associated with a greater number of juveniles. Overall, 392 A. brasiliensis stomachs were examined, and their diet comprised mainly zooplankton organisms, followed by insects and benthic crustaceans. Among the morphological measures, our data revealed that in vegetated habitats (seagrass and riparian vegetation), individuals showed a higher oral gape surface and caudal peduncle and fed predominately on epibiotic or benthic fauna, while for individuals that had bigger eyes in unvegetated habitats (mudflat), this facilitated the ingestion of zooplankton and diatoms. Furthermore, a greater relative body height recorded in unvegetated habitats enhanced swimming performance and was linked to the effects of the lowest habitat structure. The results highlight the significant effects of morphological variation on juvenile and adult food acquisition and swimming ability. Full article

Understanding how thermal variability affects marine ectotherms is essential for predicting species resilience under climate change. We investigated the physiological responses of juvenile Nodipecten subnodosus (lion’s paw scallop), offspring of two genetically distinct populations (Bahía de Los Ángeles and Laguna Ojo de Liebre), reared under common garden conditions and exposed to three temperature regimes: constant, regular oscillation, and stochastic variability. After 15 days of exposure, scallops underwent an acute hyperthermia challenge. We measured metabolic rates, scope for growth (SFG), tissue biochemical composition, and oxidative stress markers (SOD, CAT, GPx, TBARS). No significant differences were detected between populations for most traits, suggesting that phenotypic plasticity predominates over evolutionary divergence in thermal responses. However, the temperature regime significantly influenced metabolic, biochemical and oxidative stress markers, indicating that scallops in variable conditions compensated through improved energy balance and food assimilation but also showed higher oxidative stress compared to the constant regime. Following acute hyperthermic exposure, energy demand escalated, compensatory mechanisms were impaired, and scallops attained a state of physiological maintenance and survival under stress, irrespective of their population or prior thermal regime exposure. Full article

Although the Antisocial Process Screening Device (APSD) is one of the most widely used instruments for assessing psychopathic traits, the reliability estimates of the APSD show great heterogeneity across different studies. This investigation evaluated the reliability of the APSD using a reliability generalization meta-analytic technique across 158 studies (N = 75,749). The APSD demonstrated marginal to acceptable coefficient alphas ranging from 0.62 (for the Callous–Unemotional subscale) to 0.79 (for the total scale). Further moderation analysis revealed that the differences in administration formats significantly explained the variance of coefficient alphas for the APSD total and subscales, and the self-report version of the APSD manifested poorer coefficient alphas than other-report versions. The standard deviation of scale scores also partly accounted for the variance of the coefficient alphas. Overall, the APSD was found to be a reliable, practical measurement of psychopathic traits in youth, which can be widely applied in various study settings. Nevertheless, we recommend that parent- and teacher-report versions of the APSD as the preferred administering format of the measure when used for children and juveniles, while the self-report version of the APSD is recommended with caution when assessing youth psychopathy, unless multiple-assess methods are used. Full article

Background: Single-step genomic BLUP (ssGBLUP) has gained increasing interest from forest tree breeders. ssGBLUP combines phenotypic and pedigree data with marker data to enhance the prediction accuracy of estimated breeding values. However, potential errors in determining progeny relationships among open-pollinated species may result in lower accuracy of estimated breeding values. Unknown parent groups (UPG) and metafounders (MF) were developed to address missing pedigrees in a population. This study aimed to incorporate MF into ssGBLUP models to select the best parents for controlled mating and the best progenies for cloning in a tree breeding population of Eucalyptus globulus. Methods: Genetic groups were defined to include base individuals of similar genetic origin. Tree growth was measured as total height (TH) and diameter at breast height (DBH), while disease resistance was assessed through heteroblasty (the transition from juvenile to adult foliage: ADFO). All traits were evaluated at 14 and 21 months. Two genomic multi-trait threshold linear models were fitted, with and without MF. Also, two multi-trait threshold-linear models based on phenotypic and pedigree information (ABLUP) were used to evaluate the increase in accuracy when adding genomic information to the model. To test the quality of models by cross-validation, the linear regression method (LR) was used. Results: The LR statistics indicated that the ssGBLUP models without MF performed better, as the inclusion of MF increased the bias of predictions. The ssGBLUP accuracy for both validations ranged from 0.42 to 0.68. Conclusions: The best model to select parents for controlled matings and individuals for cloning is ssGBLUP without MF. Full article

Tilapia (Oreochromis spp.) is a globally important farmed fish. Analyses of genetic variation across different types of tilapia are essential for the development of superior breeding populations. We investigated the genetic structures of breeding populations of blue tilapia (Oreochromis aureus) (OA), Nile tilapia (Oreochromis niloticus) (ON), and red tilapia (Oreochromis spp.) (OS) by whole-genome resequencing. The results showed that the OS population had maintained high genetic diversity but significant genetic differentiation from the OA population. Principal component analysis, phylogenetic analysis, and genetic clustering analysis revealed a clear pattern of genetic differentiation among the three populations. The genetic structure of the ON population differed from that of the OA population but was similar to that of the OS population. Population kinship analysis revealed a close relationship between the ON and OS populations. Selective scanning analyses of three comparison groups (OA vs. ON, OA vs. OS, and ON vs. OS) revealed population-selected regions related to metabolism, endocrine, and immune systems, harboring key genes (qrsl1, pde4d, hras, ikbkb, prkag1, prkaa2, prkacb, irs2, and eif4e2). These key genes were related to growth, reproduction, and disease resistance, indicating that breeding programs have selected for these traits. Due to the lack of stable morphological characteristics of juvenile fish and the changes in external environmental conditions that lead to changes in individual morphological characteristics, SNP fingerprints were successfully constructed for the identification of the three populations based on the differences in SNPs. Based on the five core SNP markers, two combinations of SNP markers were developed to accurately identify the three populations of tilapia at the genomic level. These results provide new information about tilapia genetic resources and reference data for identification and breeding purposes. Full article

The invasive European green crab (Carcinus maenas) poses a significant ecological threat due to its rapid global spread and disruptive impact on coastal ecosystems. In the southwestern Atlantic, the northernmost population was recently recorded in the San Matías Gulf, offering a unique opportunity to study its demographic and life-history traits at the leading edge of its range. We assessed the sex ratio, population density, size distribution, and size at which 50% of females were ovigerous (SM₅₀) in the intertidal zone. Our findings revealed a male-biased sex ratio (1.50 males per female) and low population density (0.42 crabs m⁻²), suggesting early-stage establishment. A size-structure analysis showed a well-structured population with clear cohort separation in both sexes and evidence of two recruitment events. The carapace width at which 50% of females were ovigerous was estimated at 61.48 mm. Although egg-bearing females exhibited a well-marked seasonality, with the highest prevalence from May to July, their presence nearly year-round suggests an extended reproductive period and adaptability to local conditions, which may be advantageous in recently established populations, facilitating invasion success. These traits, combined with the species’ ongoing range expansion, highlight the invasive potential of C. maenas and its possible ecological impacts on the San Matías Gulf. Full article

Tryptophan hydroxylase 2 (TPH2) hydroxylates L-tryptophan to L-5-hydroxy tryptophan—the key step of 5-HT synthesis in the mammalian brain. Some mutations in the human hTPH2 gene are associated with psychopathologies and resistance to antidepressant therapy. The C1473G polymorphism in the mouse Tph2 gene decreases the TPH2 activity in the mouse brain. In the present paper, B6-1473C and B6-1473G congenic mice that were different only in the C > G substitution were used. The molecular mechanism of decrease in the mutant enzyme activity and some physiological and behavioral traits affected by this mutation were revealed for the first time. Analysis of thermal denaturation curves in vitro revealed that the C > G substitution reduces the free energy of denaturation, stability and lifetime of mutant TPH2. Later, we evaluated the effect of the 1473G allele on the hierarchical state, competition for a sexual partner in adult mice, mouse embryos, hind legs dystonia and the response to LPS treatment in young mice. No effect of this mutation on the hierarchical state and competition for a female was observed in adult males. The C > G substitution does not affect survival, body mass or the TPH activity in the brain of 19-day-old mouse embryos. At the same time, we found that the 1473G allele causes hind legs dystonia in juvenile (3 weeks old) mice, which can affect their escape capability in threatening situations. Moreover, a significant increase in the vulnerability to LPS in juvenile B6-1473G males was shown: a single ip LPS administration killed about 40% of young mutant mice, but not wild-type ones. The body mass of mutant males was lower compared to wild-type ones, which also can indirectly decrease their concurrent and reproductive success. Full article