Animals

Diarrhea in kids is a significant health and economic concern for small-scale ruminant farms. This study aims to investigate the properties of Lactobacillus amylovorus as a treatment for kids with diarrhea and its effect on the composition of the gut microbiota. A total of 20 neonatal goats (approximately 2 months old) were divided into three groups: healthy control (HC, n = 4), diarrhea (D, n = 8), and diarrhea treated with probiotic (DT, n = 8). We tracked gut microbial profiles, fecal consistency, short-chain fatty acids (SCFAs), and clinical symptoms. Probiotic-treated kids recovered fully from diarrhea within two weeks, while their untreated counterparts showed signs of clinical deterioration and gradual emaciation. Kids with diarrhea had lower microbial richness, according to alpha diversity analysis, and this was only partially restored after probiotic treatment. The kids with diarrhea had the lowest Shannon, ACE, Simpson, Dominance, Pielou-e, and Chao1 indices compared to the HC group, while the administration of Lactobacillus amylovorus significantly (p < 0.05) restored their normal enrichment in the DT group compared to the D group. The healthy group had a higher abundance of Verrucomicrobiota, while Firmicutes and Bacteroidota predominated in all groups. Bacteroides and Akkermansia predominated in the healthy and treated groups. At the genus level, analysis showed elevated levels of Escherichia-Shigella and UCG-005 in kids with diarrhea. In addition, the concentration of each SCFA in the D group was significantly (p < 0.05) lower than in the HC group. This study provides novel evidence that Lactobacillus amylovorus administration not only alleviates diarrhea but also uniquely restores the production of key SCFAs—including butyrate, acetate, and propionate—in neonatal goats, a finding not previously reported in this species. The concurrent recovery of microbial diversity and SCFA profiles highlights the dual mechanistic potential of Lactobacillus amylovorus as a gut microbiota modulator and metabolic therapeutic in young ruminants. These results lend credence to its potential as a probiotic treatment for small ruminant enteric diseases. Full article

This study evaluated the effects of dietary Myrtus communis L. extract on the production performance, immune functions, and metabolic and health status of Holstein cows throughout the transition period. Forty cows were assigned to either a control group (n = 20) or a treatment group (n = 20) receiving Myrtus communis L. extract at 1.5 mL/kg body weight per day. Milk yield and feed intake were recorded daily, whereas blood samples were collected weekly. Reproductive performance and health status were monitored. Myrtus communis L. supplementation increased dry matter intake during prepartum and early and mid-lactation and elevated prepartum glucose levels. Treated cows produced more milk in early (44.56 vs. 40.72 kg/day) (p < 0.0001), and mid-to-late lactation (42.57 vs. 37.19 kg/day) (p < 0.0001). NEFA and BHBA concentrations were lower in the treatment group (p = 0.015 and 0.019, respectively), whereas cortisol and ALT were higher around calving (p < 0.001). Despite similar prepartum inflammatory profiles, treated cows demonstrated higher TNF-α concentrations at calving (p = 0.006). The days open and insemination number per pregnancy did not differ; however, the number of ovarian cysts were less in treated cows. Overall, Myrtus communis L. extract offered at a dose of 1.5 mL/kg body weight during the transition period improved feed intake, enhanced milk production, and reduced metabolic stress, suggesting its potential as a natural additive to support energy balance and reproductive performance in cows. However, it increased the blood cortisol and ALT concentrations, which requires further investigation. Full article

Florfenicol (FFC) is widely used to treat bacterial infections in veterinary medicine; however, its pharmacokinetic characteristics in reptiles remain limited. This study investigated the pharmacokinetic profiles of FFC after intramuscular (IM) injection at doses of 20 or 30 mg/kg body weight (b.w.) in freshwater crocodiles (Crocodylus siamensis). A sample of 10 healthy crocodiles was randomly divided into two groups (n = 5 for each group) according to a parallel study design. Blood samples were obtained from pre-dose to 168 h post-administration. Plasma FFC concentrations were quantified using high-performance liquid chromatography with diode array detection (HPLC-DAD) and analyzed by non-compartmental analysis. The mean maximum plasma concentrations of FFC were 4.05 µg/mL and 6.11 µg/mL for the 20 and 30 mg/kg b.w. doses, respectively. The mean elimination half-lives of FFC were long but not significantly different (51 h). The average plasma protein binding was 37.15%. Based on the pharmacokinetics/pharmacodynamics (PK/PD) index, a single dose of FFC via IM elicited plasma concentrations above the MIC₉₀ values reported for several susceptible bacterial pathogens. Consequently, both dose levels provided plasma exposure consistent with previously reported reference MIC values. However, further PK/PD and multiple-dose investigations are needed to refine species-specific dosage regimens. Full article

The detection rate of Porcine Reproductive and Respiratory Syndrome Virus type 1 (PRRSV-1) in China has been increasing, with its growing genetic diversity and evolving pathogenicity posing significant challenges to disease control. In this study, a novel PRRSV-1 strain, designated GD18-2, was identified from a pig farm in Guangdong Province that experienced an outbreak despite vaccination with a PRRSV-2 vaccine. Whole-genome sequencing indicated that the GD18-2 strain possesses a genome length of 14,932 bp and exhibits 81.4% to 83.9% nucleotide identity with classical PRRSV-1 strains. Phylogenetic analyses based on both the complete genome and the ORF5 gene indicated that GD18-2 belongs to a distinct, new lineage. A unique amino acid deletion (positions 306–357) was identified in the non-structural protein Nsp2, along with specific mutations within the hypervariable regions of the structural proteins GP3 and GP4. Pathogenicity assessment demonstrated that GD18-2 induced fever, respiratory symptoms, and mortality in piglets. In pregnant sows, it caused reproductive failure (abortion, stillbirth, weak piglets) and was capable of vertical transmission via the placenta. This study highlights the emergence of a PRRSV-1 strain with a unique genetic background and high pathogenicity in southern China, underscoring the necessity for enhanced molecular epidemiological surveillance and updated control strategies. Recombination analysis using RDP4 revealed no significant recombination events in GD18-2. Full article

At least seven species of wild cats inhabit Colombia, and these species are also distributed throughout Mexico, Central America, and the rest of South America (jaguar, puma, jaguarundi, ocelot, margay, tigrina, and Pampas cat). A checklist and review of phylogeographic and population genetic studies on these seven wild cat species has been conducted here, as this information is vital for effective conservation programs. The jaguar is the feline species on which the most population genetic studies have been carried out in the Neotropics. In general, little genetic structure has been found at a macro-geographic scale. Genetic diversity is high in countries such as Colombia, Peru, and Bolivia, and generally throughout the Amazon basin. However, genetic diversity is more moderate or even significantly lower in Mexico and the Brazilian Atlantic Forest. Much of the genetic research on the jaguar has focused on Brazil, Mexico, and Belize, but Colombia is also very well represented in these studies. However, there is a complete or very pronounced lack of data in other areas such as Venezuela, the Guianas, some Central American countries, Paraguay, and northern Argentina. After the jaguar, the most studied feline in Neotropics from a population genetics perspective is the puma. In North America, this species has low genetic diversity, while the diversity in Central America is moderate, and South America is where genetic diversity is highest. The countries best represented in these studies are Brazil (southern of the country), Mexico, Belize, and Argentina. However, countries like Colombia, Ecuador, Peru, and Paraguay are very poorly represented in puma genetic studies. Very few genetic studies have been conducted on the jaguarundi, despite its vast geographic distribution. In northern Mexico, its genetic diversity is very low, but in countries like Colombia, Peru, and Bolivia, genetic diversity is very high. Colombia is probably the country where jaguarundis have been genetically studied most extensively. The third wild cat species with the most molecular studies in Neotropics is the ocelot, although it lags considerably behind jaguars and pumas. Its genetic diversity is low in Texas and northern Mexico, but very high, especially in countries surrounding the Amazon basin. A good number of macro-geographic studies have been conducted on the ocelot, and these studies are very representative of ocelots in countries such as Colombia (probably the best represented country), Ecuador, Peru, Bolivia, Panama, and Costa Rica. However, there are other countries where molecular studies of the ocelot have not been carried out, such as Paraguay and Argentina, with the lack of such studies in Brazil being particularly noteworthy. Very few molecular studies have been conducted on the margay. In general, its genetic diversity is very high in all the studies performed. Colombia, Peru and Bolivia are very well represented, but the lack of molecular studies in Mexico, much of Central America, and South American countries such as Brazil, Paraguay, and Argentina is striking. The tigrina is one of the Neotropical wild cat species that requires the most molecular studies to unravel its complex systematics. Only the southern Brazilian tigrina (Leopardus guttulus), which was elevated to a new species, has generated comprehensive molecular information. Molecular studies of the Andean tigrina have revealed a very complex picture that, at present, does not allow us to know exactly how many species or taxa inhabit that area of South America and, therefore, to develop a conservation program that adequately correlates with that number of taxa. Finally, in the case of the Pampas cat, molecular studies are well represented with specimens from Peru, Bolivia, Chile, Argentina, Brazil and Uruguay. Studies are needed in Paraguay, and especially in Ecuador and southern Colombia (assuming a stable population of Pampas cats exists in the latter country), where even at the molecular level, the specific taxon (one species or five species) present has not yet been determined. All this information is essential for developing effective regional and global conservation programs for these magnificent creatures. In Colombia, the development of molecular studies with the puma, the tigrina, and the Pampas cat is of special interest. Full article

This study aimed to investigate the effect of lipopolysaccharide challenge on growth performance and immune function in yellow-feathered broilers. A total of 140 yellow-feathered broilers (1-day-old) were randomly assigned to two treatments (control group and LPS group) with seven replicates of 10 chicks each. Broilers in the LPS group were injected intraperitoneally with LPS (1 mg/kg body weight) on days 21, 23, 25, and 27, while broilers in the control group were injected intraperitoneally at an equivalent volume of sterile saline on the corresponding days. After 24 hours of each injection, one chicken from each replicate was randomly selected for slaughter and sampling. The results indicate that the first LPS challenge significantly elevated jejunal mucosal IL-6 levels compared with the control group (p < 0.05). After the second injection, average daily feed intake (ADFI), average daily weight gain (ADG), and body weight gain (BWG) of broilers were decreased in the LPS group compared to the control group (p < 0.05). Additionally, IL-1β levels were increased in the liver and jejunal mucosa of broilers in the LPS group (p < 0.05). After the third injection, the ADFI, ADG, BWG and feed conversion ratio (FCR) were reduced in the LPS group compared to the control group. LPS also caused a decrease in the broiler thymus index and bursa index. In addition, the levels of IL-1β, IL-6 and IFN-γ in the jejunal mucosa of broilers in the LPS group were higher than those in the control group (p < 0.05). The levels of IL-1β and IFN-γ in the liver of the LPS group were significantly higher than those of the control group (p < 0.05). The mRNA expression of IL-1β, IL-6, and IFN-γ in the jejunum and liver of the LPS group was significantly higher than that of the control group (p < 0.05). Furthermore, the mRNA expression of TLR4 and MyD88 in both the liver and jejunal mucosa of broilers in the LPS group was significantly higher than that in the control group (p < 0.05). Following the fourth LPS injection, the ADFI, ADG, BWG, and spleen index of LPS group decreased significantly compared to the control group. Concurrently, a significant increase in the content of IFN-γ in the liver was observed. In conclusion, three times of LPS stimulation can cause significant immune damage and induce an immune stress model. Full article

Climate change in Europe can influence the predator–prey interactions, a scarcely studied topic in birds. We examined relationships between the spring passage timing of the Eurasian Sparrowhawk, a generalist peak predator, and its main bird prey species (Song Thrush, Eurasian Blackbird, Common Chaffinch, Great Tit, European Robin). All species were ringed daily (26 March–15 May) in 1982–2021 at Hel Peninsula (N Poland). In 2024, we collected pluckings to identify Sparrowhawks’ prey. Sparrowhawks’ daily migration dynamics and those for the Song Thrush, Robin and Chaffinch were correlated. Sparrowhawks’ median dates of passage showed no multi-year trend, but large variation, correlated with those of its prey and with temperatures. Adult females and males migrated through Hel early after warm February and March at wintering grounds. Young males migrated early during warm Aprils at Hel. Medians were correlated between adult males and Robins, adult females and Blackbirds, and young females and Song Thrush. This suggests that Sparrowhawks adjust their migration timing each spring to the availability of these three prey species, with some sex differences, as males are smaller than females. Identifying changes in predator–prey dynamics in response to climate change helps us understand its effect on forest ecosystems. Full article

This study investigated the effects of supplementing a commercial milk replacer with Boswellia serrata resin (BSR), a natural frankincense extract rich in boswellic acids that possess anti-inflammatory and antioxidant properties, on the growth performance, serum biochemical parameters, and meat quality of suckling lambs. Twenty-four Assaf lambs were randomly assigned to three groups (n = 8 per group): natural suckling (NS), milk replacer (MR), and MR supplemented with BSR (MR+BSR). The experimental period lasted 60 days, during which growth performance and blood indices were evaluated, followed by meat quality assessment at the end of the trial. Lambs reared artificially (MR and MR+BSR) showed greater growth performance than naturally suckled lambs, as evidenced by significantly higher final body weight (p = 0.003) and average daily gain (p = 0.002), while initial body weight did not differ among treatments (p = 0.881). Within the artificially reared groups, however, BSR supplementation did not further increase growth relative to milk replacer alone. Supplementation with BSR improved the health and metabolic profile of lambs, resulting in higher serum total protein (p < 0.001), albumin (p < 0.001), and globulin (p < 0.001) concentrations. Moreover, BSR supplementation reduced the increase in aspartate aminotransferase (p < 0.001) and alanine aminotransferase (p < 0.001) activities observed in the MR group. No significant differences were detected in meat proximate composition (p > 0.05). However, meat from the NS group was significantly harder (p = 0.002) and more cohesive (p = 0.003) than meat from lambs fed MR or MR+BSR. In addition, the MR+BSR group produced meat with a higher redness (a*) value (p = 0.041), indicating an improved color quality. In conclusion, supplementing milk replacers with BSR enhanced the physiological and biochemical health of suckling lambs and enhanced specific meat quality traits, suggesting its potential as a natural functional additive in artificial rearing systems. Full article

Dry matter intake (DMI) in dairy cows is a critical indicator of nutrient intake from feed, serving as the cornerstone of precision feeding practices, playing a critical role in improving production efficiency and enhancing the quality of dairy products. To address the high costs of traditional measurement methods and the structural complexity and large parameter counts of neural network models, this study proposes a Stacking ensemble learning model to assess DMI, with model parameters optimized using the Tuna Swarm Optimization (TSO) algorithm to enhance assessment accuracy, taking cow body weight, lying duration, lying times, rumination duration, foraging duration, walking steps, and the concentrate-to-roughage feed ratio as input variables. To further improve TSO’s search efficiency and spatial exploration, this study introduces Sine–Logistic chaotic mapping, Levy flight, and Gaussian random walk strategy to optimize the TSO algorithm, developing the improved Tuna Swarm Optimization (ITSO). ITSO-optimized Stacking model achieved superior performance in DMI assessment, with an accuracy of 95.84%, significantly outperforming SVR, RF, DT, GBR, ETR, and AdaBoost models. This study provides a robust tool for precision feeding, contributing to optimizing cow feeding strategies, improving farm efficiency, and supporting sustainable dairy farming practices. Full article

Visual orthopedic gait assessment in dogs is recognized as subjective and is limited by interobserver variability. Objective detection of lameness is offered by biomechanical analysis, where asymmetry between limbs is quantified through kinematic parameters and symmetry indices. However, the minimum number of trials (full stride cycles) required to reliably discriminate lameness has remained a challenge. In this study, six healthy adult dogs were used. Mild, reversible lameness was induced in one forelimb using a cotton pad. Dogs were walked along a straight runway, and kinematic data were captured with a high-speed video camera. Stride length (SLE), support time (ST), and elbow range of motion (ROM) were measured. Symmetry indices (for linear and temporal parameters) and the symmetry angle (for angular parameters) were computed. The asymptotic distribution of these indices was derived using the delta method, which allowed for the construction of confidence intervals (CIs) and hypothesis tests for an asymmetry threshold of 3%. The number of trials required to achieve reliable detection was estimated through statistical simulations. Results indicated that the required number of trials was highly dependent on both the kinematic parameter and the magnitude of asymmetry. While detecting subtle asymmetries (≈4%) required a high number of trials (up to 347 for stride length), the requirements decreased substantially for more pronounced lameness. For a true asymmetry of 6%, 11–39 trials per limb were sufficient to achieve 80–90% power. It is concluded that the collection of only five trials is insufficient for detecting mild asymmetries. A statistical framework and practical recommendations for kinematic gait studies in dogs are provided. Full article

Marbling, or intramuscular fat (IMF), is a primary determinant of high-quality beef, defining key sensory attributes and nutritional value. Yunling (YL) cattle, an indigenous breed from Yunnan, China, are renowned for their superior marbling, yet the underlying molecular mechanisms remain unclear. This study employed an integrated transcriptomic, lipidomic, and amino acid metabolomic approach to systematically compare the multi-omics profiles of the longissimus dorsi muscle among YL, Angus (AGS), and Simmental (XMTE) cattle. Transcriptome analysis identified 2053 and 2156 differentially expressed genes (DEGs) in XMTE vs. YL and AGS vs. YL, respectively. These DEGs were primarily enriched in the PI3K-Akt and MAPK signaling pathways, as well as oxidative phosphorylation. Lipidomic analysis revealed a distinct lipid profile in YL cattle, identifying 27 characteristic lipid molecules (e.g., SM(d20:0/24:1), DG(16:0/18:1(11Z)/0:0)) compared to XMTE and 17 differential lipids compared to AGS. The amino acid metabolome showed that Beta-Alanine and L-Aspartic acid levels in YL were 42.6% and 54.8% lower than in XMTE, respectively (p < 0.01), and levels of several functional amino acids were significantly reduced compared to AGS. Weighted Gene Co-expression Network Analysis (WGCNA) constructed a gene-metabolite network, identifying key modules strongly correlated with lipid and amino acid metabolism (|r| > 0.6). Within these modules, energy metabolism-related genes such as NDUFB1, COX7C, and IDH3B, along with signal transduction genes including ITGB3, PDGFRA, and FN1, were found to synergistically regulate marbling formation in YL cattle. This study systematically elucidates the molecular mechanisms underlying both marbling formation and the nutritional characteristics of meat in Yunling cattle. This provides a theoretical foundation for genetic improvement and offers potential molecular targets to enhance both marbling and overall meat quality in other indigenous cattle breeds worldwide. Full article

Background: Pulmonary nematodes are an underrecognized cause of respiratory disease in domestic cats, with diagnosis often complicated by nonspecific clinical signs and limitations of fecal-based testing. Methods: This study aimed to assess the prevalence of feline lungworms in Poland and to describe lung ultrasound findings in a separate clinical cohort of cats. A nationwide coprological survey was conducted using pooled fecal samples from 1058 cats examined with Baermann and flotation techniques, supported by molecular diagnostics where available. Results: Overall, 9.83% of cats were positive for at least one parasite. Aelurostrongylus abstrusus was the most frequently detected lungworm (7.18%), followed by Eucoleus aerophilus (2.17%) and Troglostrongylus brevior (0.47%). Lungworm infections were strongly associated with younger age and showed marked seasonal variation, with higher prevalence in autumn and winter. Lung ultrasound consistently revealed diffuse B-line artifacts and other signs of reduced lung aeration, often in the absence of severe respiratory signs. Following treatment with topical imidacloprid/moxidectin, complete resolution of ultrasonographic abnormalities and clinical signs was observed. Conclusions: These findings confirm that feline pulmonary nematodes are present in Poland and may be underdiagnosed. Lung ultrasound represents a sensitive and non-invasive tool for detecting and monitoring lung involvement, but should be interpreted in conjunction with epidemiological data, parasitological results and therapeutic response. Full article

Sea turtles are increasingly being used as bioindicators of marine pollution, yet baseline data on trace elements in the blood are still limited. This study quantified magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) in green turtles (Chelonia mydas) (55 plasma samples and 71 cell concentrate samples) and olive ridleys (Lepidochelys olivacea) (101 plasma samples and 65 cell concentrate samples) sampled off the Caribbean (Tortuguero) and Pacific (Ostional) coasts of Costa Rica in 2003–2004. The metals were measured using atomic absorption spectroscopy; whole-blood concentrations were derived from the plasma and the erythrocyte values. The present results were compared with published datasets to evaluate the spatial and temporal patterns of metal exposure over the past two decades. The essential elements showed matrix-specific distributions, with Mg and Cu higher in the plasma, and Fe and Zn higher in the cell concentrates in both species (p < 0.001). C. mydas generally exhibited higher Cu, Fe and Zn levels in the plasma (p < 0.001), whereas L. olivacea showed markedly higher Cd levels (p < 0.001). Overall, the Pb levels were low as compared with many other rookeries worldwide. These data provide one of the earliest, large-sample baselines for trace elements in sea turtle blood in the Eastern Tropical Pacific and Western Caribbean and underscore the value of blood-fraction analysis for long-term ecotoxicological monitoring. Full article

This study investigated the nutritional value of enzymolytic soybean meal (ESBM) in growing pigs through two experiments. Experiment 1 evaluated the digestible energy (DE) and metabolizable energy (ME) values using twenty-two crossbred pigs (Duroc × Landrace × Yorkshire; initial BW 36.47 ± 0.63 kg) in a replicated 11 × 3 incomplete Latin square design. The dietary treatments comprised a corn-based diet and ten test diets formulated by substituting 30% corn with ESBM. Experiment 2 evaluated standardized ileal digestibility (SID) of amino acid (AA) through a 10 × 6 incomplete Latin square design involving ten pigs (Duroc × Landrace × Yorkshire; initial BW: 21.30 ± 1.38 kg) fitted with T-cannulas. All experimental diets contained 40% ESBM as the sole source of AA and 0.2% titanium dioxide as an indigestible marker. The results revealed variations in the chemical composition of ESBM samples, with coefficients of variation (CV) exceeding 9% for all analyzed components except for gross energy (GE), which had a CV of 4.65%. The mean DE and ME were 16.46 MJ/kg DM (13.82 to 19.13 MJ/kg DM) and 15.73 MJ/kg DM (12.79 to 18.77 MJ/kg DM), respectively. The best-fit prediction equations for DE and ME were as follows: DE (MJ/kg DM) = −26.31 + (2.74 × GE) − (0.17 × CP) (R² = 0.76, p < 0.01) and ME (MJ/kg DM) = −28.45 + (2.85 × GE) − (0.19 × CP) (R² = 0.70, p = 0.01). The mean SID of Lys, Met, Thr, Trp, Val, and total AA were 81.72% (71.19 to 95.64%), 81.36% (45.59 to 95.76%), 76.19% (59.67 to 90.40%), 50.61% (15.40 to 74.13%), 81.23% (69.39 to 92.99%), and 84.29% (67.36 to 96.56%), respectively. In this study, ESBM5 exhibited higher energy content and AA digestibility, whereas ESBM8 demonstrated the lowest nutritional value. The ash content exhibited the strongest negative correlation with DE (r = −0.75; p < 0.05) and ME (r = −0.76; p < 0.05), while Trp showed the strongest positive correlation with the SID of AA. The chemical composition of ESBM can be effectively used to predict DE, ME, and SID of AA in growing pigs. Full article

Distant hybridization induces genomic instability in offspring, driving the occurrence of gene recombination and mutation. Analysis of the genomic genetic composition can be used to infer the genetic evolutionary relationships between species. Based on the improved diploid carp (IDC) and the improved diploid scattered mirror carp (IDMC) lineages derived from distant hybridization between female common carp and male blunt snout bream, this study analyzed the genetic variation in their mitochondrial genomes to investigate the impact of distant hybridization on mitochondrial DNA (mtDNA) structural variation. Analysis of complete mitochondrial genome sequence structure and composition revealed subtle structural divergence across generations in both the IDC and IDMC lineages. Analysis of the protein-coding gene sequence structure demonstrated mitochondrial genome structure instability in nascent hybrid diploid lineages. Yet, subsequent self-crossing significantly narrowed the range of structural variation within each lineage. Furthermore, analysis of the genetic variation in the mitochondrial genome sequence structure revealed that paternal base insertions occurred in both F₁ lineages, accompanied by mutations predominantly consistent with those in crucian carp. The results of this study also indicated that the strictness of the paternal mtDNA elimination mechanism varied significantly among polymorphic individuals across different generations of the hybrid lineages, reflecting the randomness of paternal leakage. Full article

In the past, bacteria detected in the mare’s uterus were generally interpreted as a sign of endometritis, since the uterus was considered a sterile environment. This assumption has been challenged by the introduction of culture-independent molecular techniques, particularly 16S rRNA amplicon sequencing, which have demonstrated that healthy mares harbor an endometrial microbiota. The aim of this study was to characterize the endometrial microbiota of healthy mares and to determine whether microbial composition differs between estrus and diestrus. Endometrial samples were collected from eleven healthy Standardbred mares during estrus and diestrus and analyzed by sequencing the V1–V2 region of the bacterial 16S rRNA gene. A total of 24 bacterial phyla and 599 genera were identified. At the phylum level, Firmicutes, Proteobacteria, Bacteroidota, and Actinobacteriota accounted for most of the relative abundance, while the most abundant genera were Staphylococcus, Acinetobacter, Sphingomonas, Corynebacterium, Streptococcus, Clostridium, and Pseudomonas. Alpha diversity was significantly higher during estrus, likely due to hormonally mediated changes in cervical opening and local immunity. Beta diversity analyses showed substantial overlap between estrus and diestrus samples. The phase of the cycle had a weak effect on microbiota structure, while inter-individual differences between mares explained a larger proportion of the observed variation. These findings suggest that the uterine microbiota of healthy mares is largely stable across the estrous cycle, with phase-dependent and mare-specific fluctuations in microbial composition. Full article

This study examines risky decision-making in a free-ranging population of Balinese long-tailed macaques (Macaca fascicularis fascicularis), addressing gaps in research that have largely focused on captive primates and have rarely considered individual differences by age and sex. Thirty-three macaques of different age–sex classes were tested using a choice task contrasting a guaranteed small reward with a probabilistic larger reward. At the group level, macaques showed no preference for safe or risky options. However, substantial individual variation emerged: some individuals were risk-prone, others risk-averse, and many indifferent. Notably, age and sex interacted in shaping risk preferences. Among males, adults and juveniles were more risk-prone than younger adults, whereas among females, adults were more risk-prone than juveniles. Juveniles also displayed outcome-dependent flexibility, choosing the risky option more often after a previous successful risky choice, consistent with a win–stay strategy. Like in rodents, this pattern may reflect adaptive learning during developmental transitions. Importantly, the observed behavioral differences were not due to misunderstanding of the task, as macaques reliably chose the larger option when outcomes were visible. This pronounced individual variability in primate risk preferences underscore the importance of considering demographic factors when characterizing species-typical risk preferences. Full article

Twin births in dairy cattle present challenges for producers, resulting in increased prevalence of health issues for both cows and calves, thereby impacting profitability. Genome-wide association study (GWAS) analyses of the twinning rate in Holstein cattle have reported the most significant genomic association with twinning rate in a region containing two strong candidate genes: follicle-stimulating hormone receptor (FSHR) and luteinizing hormone/chorionic gonadotropin receptor (LHCGR). Coding-sequence variants of these genes were not associated with the twinning rate, suggesting that one of the two genes is differentially expressed in association with the twinning rate. Granulosa cells were collected from 38 Holstein cows that were selected to provide similar representation of genotypes for the twinning rate quantitative trait locus (QTL). RNA was extracted from granulosa cells and gene expression was assessed by quantitative PCR with data analyzed by the ΔΔCT method. Association of gene expression with QTL genotype was tested by the Kruskal–Wallis test with the QTL genotype based on the SNP most significantly associated with twinning rate. QTL genotype was significantly associated (p = 1.88 × 10⁻⁸) with the expression of FSHR but was not associated with LHCGR expression (p = 0.18). The increased FSHR expression was associated with an increasing copy number of the G allele and thus an increased twinning rate. Full article

Aquaculture output, sustainability, and profitability can be enhanced by using functional feed additives. The effect of supplementation with two different dietary levels of propylene glycol (PG) and essential oils (EOs) was evaluated in Nile tilapia. A total of 150 juvenile fish were randomly allocated into five groups. Growth performance, feed utilization, serum biochemistry, hematology, and gene expression were assessed. PG supplementation significantly improved growth performance, feed conversion, protein efficiency, and energy utilization. Both additives significantly reduced cortisol and glucose levels and altered liver enzymes and lipid profiles. PG improved immunological indices, while hematological responses were dose-dependent; both EOs and PG increased hematocrit, mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH). Moreover, the high PG dose significantly increased platelet counts, reduced hemoglobin (Hb), and elevated hematocrit. Additionally, EOs significantly upregulated antifreeze protein IV (AFPIV) and fat metabolism-related genes in a dose-dependent manner, indicating a potential role in lipid mobilization and stress tolerance. Expression analysis of the immunoglobulin H (IGMH) gene revealed a significant increase in PG-supplemented groups, suggesting its immunostimulatory potential. Overall, PG enhanced immunity and growth performance, while EOs promoted AFPIV and fat metabolism gene expression. Therefore, PG and EO supplementation could serve as an effective functional strategy to enhance O. niloticus growth, stress adaptation, and immune resilience. Full article