Search Results (23)

The replacement of fishmeal with plant-based proteins in aquafeeds is key for sustainable aquaculture but may compromise filet pigmentation in rainbow trout (Oncorhynchus mykiss), a quality trait dependent on astaxanthin (Ax) deposition and metabolism. This study aimed to assess the effects of graded fishmeal replacement with a plant protein blend on Ax retention, pigmentation, lipid metabolism, and gut microbiota composition. Rainbow trout were fed three isoenergetic diets containing 60%, 36%, or 12% fishmeal, each supplemented with equal amounts of natural Ax from Haematococcus pluvialis, for 12 weeks. Ax retention, pigmentation, plasma metabolites, lipid digestibility, and distal intestinal microbiota were evaluated. The high plant protein diet (12% fishmeal) significantly reduced Ax concentrations in filet and plasma and decreased dorsal and belly pigmentation scores (p < 0.05). It also lowered plasma cholesterol and bile acid levels by 18–30%, reduced di-esterified Ax digestibility by 15%, and lipid absorption efficiency by 12%. The gut microbiota shifted significantly, with a marked reduction in Bacillaceae, positively correlated with Ax retention and pigmentation. Fish fed High Plant Meal diets exhibited impaired performance parameters, along with reduced lipid accumulation in the liver. High plant meal compromises Ax bioavailability by altering cholesterol–bile acid metabolism and gut microbiota, impairing Ax absorption. However, moderate inclusion of plant meal preserved pigmentation, underscoring the need for dietary cholesterol management and microbiota modulation in plant-based aquafeeds. Full article

Urbanization reshapes bird communities by filtering species according to their ecological traits, often reducing richness, altering relative abundances, and favoring a subset of functionally tolerant species that dominate urban assemblages. Some native taxa are able to inhabit cities, even using them as stepping stones for range expansion. We examined urban habitat use, microhabitat selection, and potential niche partitioning between two range-expanding thrushes (Austral Thrush [Turdus falcklandii] and Rufous-bellied Thrush [Turdus rufiventris]) in two urban settlements in the Pampas region, Argentina. Using 131 transects across green areas and urbanized zones, we related abundance patterns to habitat features at the transect scale and evaluated microhabitat selection at the individual level. Austral Thrush abundance increased with herbaceous cover, tree cover, and even concrete surfaces, suggesting a relatively high tolerance to fragmented green spaces within dense urban matrices. In contrast, Rufous-bellied Thrush showed a positive association with tree cover, avoided tall buildings, and reached higher abundance in the smaller city, consistent with its recent arrival in the region and preference for less intensively urbanized environments. Microhabitat data revealed marked vertical stratification: Austral Thrush foraged almost exclusively at ground level on grassy or bare substrates, while Rufous-bellied Thrush used trees, shrubs, and vines more frequently. These differences reflect fine-scale resource partitioning that may contribute to reducing niche overlap and favor the coexistence of both species in recently colonized urban areas, while recognizing that such dynamics occur within broader bird assemblages where multiple species interact and compete for space and resources. Our findings highlight that even closely related species can respond divergently to urban structure, and that maintaining structural and substrate heterogeneity within cities may help support native bird diversity. Full article

Australian elapid snakes possess potent procoagulant venoms, capable of inducing severe venom-induced consumption coagulopathy (VICC) in snakebite victims through rapid activation of the coagulation cascade by converting the FVII and prothrombin zymogens into their active forms. These venoms fall into two mechanistic categories: FXa-only venoms, which hijack host factor Va, and FXa:FVa venoms, containing a complete venom-derived prothrombinase complex. While previous studies have largely focused on human plasma, the ecological and evolutionary drivers behind prey-selective venom efficacy remain understudied. Here, thromboelastography was employed to comparatively evaluate venom coagulotoxicity across prey classes (amphibian, avian, rodent) and human plasma, using a taxonomically diverse selection of Australian snakes. The amphibian-specialist species Pseudechis porphyriacus (Red-Bellied Black Snake) exhibited significantly slower effects on rodent plasma, suggesting evolutionary refinement towards ectothermic prey. In contrast, venoms from dietary generalists retained broad efficacy across all prey types. Intriguingly, notable divergence was observed within Pseudonaja textilis (Eastern Brown Snake): Queensland populations of this species, and all other Pseudonaja (brown snake) species, formed rapid but weak clots in prey and human plasma. However, the South Australian populations of P. textilis produced strong, stable clots across prey plasmas and in human plasma. This is a trait shared with Oxyuranus species (taipans) and therefore represents an evolutionary reversion towards the prothrombinase phenotype present in the Oxyuranus and Pseudonaja last common ancestor. Clinically, this distinction has implications for the pathophysiology of human envenomation, potentially influencing clinical progression, including variations in clinical coagulopathy tests, and antivenom effectiveness. Thus, this study provides critical insight into the ecological selection pressures shaping venom function, highlights intraspecific venom variation linked to geographic and phylogenetic divergence, and underscores the importance of prey-focused research for both evolutionary toxinology and improved clinical management of snakebite. Full article

The likely increase in the frequency and severity of droughts with climate warming will pose an enormous challenge for the conservation of forest biodiversity. Documenting the response of species to recent droughts can inform future conservation actions. Mammals that breed and mature slowly may be especially vulnerable to drought-induced disruption to breeding. The yellow-bellied glider (Petaurus australis, Shaw) is a threatened low-density, arboreal marsupial of eastern Australia. Following a severe drought in 2019, one population had declined by 48% by 2021. The present study investigated whether this population had recovered 3–4 years (2022 and 2023) after that drought. Audio surveys of this highly vocal species were conducted at 42 sites, sampling > 1000 h per year, and producing recordings of 2038–2856 call sequences. The probability of occupancy varied little across the two survey years (0.92–0.97). Local abundance in 2023 had returned to pre-drought levels (45% of occupied sites had ≥3 individuals compared to 6% in 2021). These findings show a recovery from a drought-induced decline required at least 3 years, in keeping with the slow life history traits of this species. This study highlights the importance of considering a species’ life history strategy when evaluating its sensitivity to drought. Full article

This study identified genomic variants and potential candidate genes associated with 11 primal cut traits (back fat, belly fat, total fat, loin fat, ham fat, picnic fat, butt fat, loin intramuscular fat content, ham side fat, shoulder dorsal fat, and belly side fat thicknesses) in Canadian commercial crossbred pigs. Genome-wide association studies using whole genome sequencing data were conducted using genotyping data from 1118 commercial crossbred pigs. This analysis revealed multiple QTLs across chromosomes SSC1, 2, 3, 6, 7, 9, 14, 15, and 17, associated with fat traits. Notably, an SNP at position 160,230,075 bp on SSC1 was significantly associated with multiple fat traits, including belly fat, butt fat, ham fat, loin fat, picnic fat, and side fat. Common genes in windows associated with multiple traits, such as MC4R, RNF152, and CDH20 were shared across these traits, suggesting pleiotropic effects. Some of the QTLs were near previously identified QTLs or candidate genes that have been reported to be linked to meat quality traits associated with backfat and intramuscular fat. Other candidate genes identified in the study include TNFRSF11A, LEPR, and genes from the SERPINB family, highlighting their roles in fat deposition and composition. Additional candidate genes were also implicated in regulation of fat metabolism, adipogenesis, and adiposity. These findings offer valuable insights into the genetic architecture of fat traits in pigs, which could inform breeding strategies aimed at improving the pork quality. Full article

The improvement of carcass traits is a key focus in pig genetic breeding programs. To identify quantitative trait loci (QTLs) and genes linked to key carcass traits, we conducted a genome-wide association study (GWAS) using whole-genome sequencing data from 1118 commercial pigs (Duroc sires and Yorkshire/Landrace F1 dams). This study focused on six phenotypes: iodine value, belly firmness, belly side fat, total side thickness (belly SThK), belly subcutaneous fat (Subq), and belly seam. Phenotypes were measured using image analysis, DEXA, and fatty acid profiling, and genotyping was performed using low-pass sequencing (SkimSeq). After quality control, 18,911,793 single nucleotide polymorphisms (SNPs) were retained for further analysis. A GWAS was conducted using a linear mixed model implemented in GCTA. Key findings include a significant QTL on SSC15 (110.83–112.23 Mb), which is associated with the iodine value, containing genes such as COX15, CHUK, SCD, and HIF1AN, which have known roles in fatty acid metabolism. Additionally, PNKD, VIL1, and PRKAG3 (120.74–121.88 Mb on SSC15) were linked to belly firmness, influencing muscle structure and fat composition. Three QTLs for belly side fat were identified on SSC1, SSC2, and SSC3, highlighting genes like SLC22A18, PHLDA2, and OSBPL5, which regulate fat deposition and lipid metabolism. The results provide novel molecular markers that can be incorporated into selective breeding programs to improve pork quality, fat distribution, and meat composition. These findings enhance our understanding of the genetic mechanisms underlying carcass belly traits while offering tools to improve pork quality, optimize fat composition, and align with consumer preferences in the meat production industry. Full article

The use of electronic sow feeders (ESFs) during lactation has been associated with weaning of heavier piglets when compared to traditional feeders, with a lower amount of sow feed per kg of weaned piglet, improved welfare of the sow, and no negative effects on body condition or metabolic traits at weaning or subsequent reproductive yields. However, there have been no studies assessing the possible effects of ESF use on the lifelong development of the progeny. This study reveals that piglets weaned from sows fed with ESFs were heavier than those from sows fed with traditional feeders (5.91 ± 1.45 vs. 5.58 ± 1.23 kg, p < 0.005), with a lower amount of feed per kg of weaned piglet (2.41 ± 0.42 vs. 1.88 ± 0.28 kg, p < 0.0005). Subsequent differences in body weight increased due to a higher average daily weight gain during both the periods of nursery (0.332 ± 0.92 vs. 0.312 ± 0.80 kg/day, p < 0.01) and growing–finishing (0.921 ± 0.11 vs. 0.871 ± 0.09 kg/day, p < 0.001). Finally, the weights of the carcasses and primal pork pieces (ham, shoulder, loin, and belly) were also higher in pigs from sows fed with ESFs (p < 0.001 for all). Full article

In the meat industry, the quality grading system is commonly applied to classify carcasses based on quality and value. Presently, to facilitate consumer convenience, pork bellies are prepared into slices and retailed in supermarkets and butchers. The objective of this study was to assess the effect of quality grade (QG) and retail cutting manner on the quality properties of pork bellies. Thirty-two bellies with different QGs: QG1⁺, 1, 2, and off-grade (n = 8 each) randomly collected from a commercial slaughterhouse were used. Each belly was cut into 3 portions: A (5–10th rib, cranial edge), B (11–15th rib), and C (without rib, caudal edge) according to the commonly used retail cutting manner. Samples were subjected to chemical composition, quality traits, and aroma analysis. Fat content was highest in QG1⁺ and lowest in off-grade and distributed at a higher level in portions A and B than in portion C in all QGs (p < 0.05). Off-grade was associated with higher shear force and chewiness values and lower levels of palmitic and stearic acids, regardless of the cutting portion. The bellies used in this study exhibited variations in chemical composition and quality properties not only among the QGs but also across the cutting portions within each QG. Full article

Pork belly, prized for its unique flavor and texture, is often overlooked in breeding programs that prioritize lean meat production. The quality of pork belly is determined by the number and distribution of muscle and fat layers. This study aimed to assess the number of pork belly layers using deep learning techniques. Initially, semantic segmentation was considered, but the intersection over union (IoU) scores for the segmented parts were below 70%, which is insufficient for practical application. Consequently, the focus shifted to image classification methods. Based on the number of fat and muscle layers, a dataset was categorized into three groups: three layers (n = 1811), five layers (n = 1294), and seven layers (n = 879). Drawing upon established model architectures, the initial model was refined for the task of learning and predicting layer traits from B-ultrasound images of pork belly. After a thorough evaluation of various performance metrics, the ResNet18 model emerged as the most effective, achieving a remarkable training set accuracy of 99.99% and a validation set accuracy of 96.22%, with corresponding loss values of 0.1478 and 0.1976. The robustness of the model was confirmed through three interpretable analysis methods, including grad-CAM, ensuring its reliability. Furthermore, the model was successfully deployed in a local setting to process B-ultrasound video frames in real time, consistently identifying the pork belly layer count with a confidence level exceeding 70%. By employing a scoring system with 100 points as the threshold, the number of pork belly layers in vivo was categorized into superior and inferior grades. This innovative system offers immediate decision-making support for breeding determinations and presents a highly efficient and precise method for assessment of pork belly layers. Full article

The quality of rice, evaluated using multiple quality-related traits, is the main determinant of its market competitiveness. In this study, two japonica rice varieties with significant differences in quality-related traits were used as parents to construct two populations, BC₃F₂ and BC₃F_2:3, with Kongyu131 (KY131) as the recurrent parent. A genetic linkage map was constructed using the BC₃F₂ population based on 151 pairs of SSR/InDel polymorphic markers selected between the parents. Grain-shape-related traits (grain length GL, grain width GW, and length-to-width ratio LWR), chalkiness-related traits (white-core rate WCR, white-belly rate WBR, white-back rate BR, and chalkiness rate CR), and amylose content (AC) were investigated in the two populations in 2017 and 2018. Except for BR and CR, the traits showed similar characteristics with a normal distribution in both populations. Genetic linkage analysis was conducted for these quality-related traits, and a total of 37 QTLs were detected in the two populations. Further validation was performed on the newly identified QTLs with larger effects, and three grain shape QTLs and four chalkiness QTLs were successfully validated in different environments. One repeatedly validated QTL, qWCR3, was selected for fine mapping and was successfully narrowed down to a 100 kb region in which only two genes, LOC_0s03g45210 and LOC_0s03g45320, exhibited sequence variations between the parents. Furthermore, the variation of LOC_Os03g45210 leads to a frameshift mutation and premature protein termination. The results of this study provide a theoretical basis for positional cloning of the qWCR3 gene, thus offering new genetic resources for rice quality improvement. Full article

The objective of the study was to compare carcass and meat quality among Lithuanian White, Lithuanian Indigenous Wattle and conventional hybrids as well as consumer sensory evaluations. The pigs were slaughtered at a live weight of approximately 95–100 kg. After 24 h of slaughter, carcasses were evaluated and sampled for the analysis of meat quality traits of loins and consumer evaluation of cooked loins and baked bellies. The pigs of both Lithuanian breeds had higher backfat thickness and depth of underbelly but lower loin area compared with hybrids. However, more fatty local breeds had higher intramuscular fat content but lower cholesterol content than hybrids. The loins from local pigs displayed higher pH and colour with lower lightness and yellowness but higher redness and also lower cooking loss, shear force and hardness than conventional hybrids. Pork from lean hybrids had a higher proportion of polyunsaturated fatty acids and more favourable lipid quality indices such as atherogenic (AI) and thrombogenic (TI) indices and the hypocholesterolemic/hypercholesterolemic (h/H) ratio; however, the peroxidisability index (PI) and iodine value (IV) were less favourable compared with local pigs. Consumers evaluated cooked loins and baked bellies. The loins from local breeds scored higher in juiciness, taste and overall acceptability compared with conventional hybrids. However, a higher overall acceptability was observed for the lean bellies of hybrids. The results can be used to increase pork consumption choices. Full article

The influence of feeding Atlantic salmon for 90 days on diets that excluded fishmeal (FM) and fish oil (FO) was examined for influence on various quality traits. In addition, the effect of adding krill meal (KM; 0%, 2.5%, and 5%), as a putative feed palatant was also examined. Total replacement of FM/FO had a limited effect on production characteristics, affecting percentage yields of headed and gutted control fish and their standard length (p < 0.05). Variances between dietary groups were observed for pigmentation, and plant protein-based KM-free-fed fish returned deeper hues across their belly, NQC (Norwegian Quality Cut), and back portions (p < 0.03). No differences were measured for relative fin condition. δ¹³C and δ¹⁵N concentrations were lower and higher, respectively (p < 0.05) for fish fed the FM/FO-based diet. δ¹³C:δ¹⁵N likewise differed between treatments with FM/FO-fed salmon expressing higher ratios. Fillet mechanical characteristics varied with fish fed on animal protein-based diets, without KM expressing higher springiness and resilience (p < 0.05). Fish fed plant-based diets were generally preferred by younger taste testers. The results from this trial illustrate that FM/FO can be completely removed from salmon diets without problematic effects on quality and palatability attributes. Full article

The study investigated the effect of on-farm rest period (RP) on carcass composition, meat quality, and stress indicators of culled sows. The study was conducted on 84 Large White × Landrace culled sows, which were divided into seven groups (n = 12) with respect to the duration of the on-farm rest period: no rest period (N-RP) group and 1 to 6 weeks of on-farm rest period (1–6 RP). After completion of the on-farm RP, each group of culled sows was slaughtered and the carcass and meat quality traits were determined. Sows from 6-RP had a significantly higher dressing percentage and backfat thickness and, together with sows from 5-RP, a higher shoulder weight. The highest shoulder percentage was found in the 3-RP and 4-RP groups, while 1-RP had the highest percentage for the belly–rib part. At the same time, RP influenced the final pH values (pH₂₄ SM and pH₂₄ LL) measured in the longissimus thoracis et lumborum (LT) and in the musculus semimembranosus (SM), as well as drip loss, thawing loss, cooking loss, and tenderness. As far as the stress indicators are concerned, statistical differences between groups were only found in the cortisol level, which was lowest in 6-RP. The results show that RP has a positive effect on meat quality traits and carcass composition. In addition, prolonged RP has a positive effect on the levels of stress indicators. Full article

The increase in market demand and economic value of Canadian pork primal cuts has led to a need to assess advanced technologies capable of measuring quality traits. Fat and lean composition were measured using a Tellspec near-infrared (NIR) spectroscopy device to predict the pork belly fat iodine value (IV) and loin lean intramuscular fat (IMF) content in 158 pork belly primals and 419 loin chops. The calibration model revealed a 90.6% and 88.9% accuracy for the Tellspec NIR to predict saturated fatty acids (SFA) and IV, respectively, in the belly fat. The calibration model accuracy for the other belly fatty acids revealed an accuracy of 66.3–86.1%. Using the Tellspec NIR to predict loin lean IMF reported a lower accuracy for moisture (R² = 60) and fat % (R² = 40.4). This suggests that Tellspec NIR spectroscopy measures on the pork belly primal offers a cost-efficient, rapid, accurate, and non-invasive indicator of pork belly IV and could be used for the classification for specific markets. Full article

Rice holds an important sociocultural meaning in Europe, and especially in the gastronomy of its Mediterranean regions, as it is used for world-famous recipes such as Risotto in Italy and Paella in Spain. Paella is prepared with highly appreciated pearled (white-core) rice cultivars such as Bomba or Montsianell, while Risotto is prepared with white-belly Carnaroli cultivar among others. Pearled rice grains have a limited and enclosed translucent zone which is physicochemically different from stress-induced chalky grains present in any rice cultivar at a low rate, and whose opaque area covers at least three quarters of the grain surface. We have studied for the first time the physicochemical aspects of grains from pearled white-belly, white-core and crystalline rice grains of Mediterranean japonica rice cultivars in comparison with their defective stress-induced chalky grains in order to shed some light on their differences. Spanish Bomba and Montsianell white-core (pearled) cultivars have similar physicochemical behaviours but are clearly different from white-belly Carnaroli cultivar. Furthermore, their pearled fractions differ in some traits from stress-induced chalkiness, especially in terms of amyloplastic integrity, relative amylose content and relative storage protein content. This study establishes some physicochemical differences between white-belly, white-core and stress-induced defective chalky grains and will guide future studies to unravel this much-appreciated pearl character in the Mediterranean gastronomy. Full article