Animals最新文献

Optimizing semen collection is critical for maximizing genetic advancement and reproductive efficiency in livestock. While exogenous hormones can enhance ejaculate quantity and quality, short windows of biological activity often limit their efficacy. This study was conducted in northern-arid Mexico (25° N, 103 W) to evaluate the comparative effects of oxytocin (OXYT) and carbetocin (CARB) administration on semen quality in French-Alpine bucks. Males (n = 12) were allocated into three groups and received intravenous treatments 10 min prior to artificial vagina collection: (1) OXYT (10 UI oxytocin buck^-1), (2) CARB (0.2 mg 100 kg^-1 LW^-1), and (3) CONT (1 mL saline buck^-1). The same bucks received all three treatments separately. CARB outperformed both groups (p ≤ 0.05), improving all evaluated parameters (p ≤ 0.05): ejaculated volume (i.e., increased by 103%), sperm concentration, mass and progressive motility, total sperm count, viability, normal morphology, plasma membrane functionality, acrosome integrity, and chromatin dispersion. Crucially, CARB doubled (p ≤ 0.05) the available projected or theoretical number of doses for intravaginal artificial insemination (POTNDIAI), followed by the OXYT and CONT groups, with 11.14 POTNDIAI each. Therefore, CARB emerges as a highly effective, accessible pharmacological strategy for semen collection protocols, substantially enhancing sperm yield and structural quality in breeding bucks. Ultimately, by bridging advanced reproductive physiology with practical smallholder farming, this methodological optimization provides a viable strategy to enhance reproductive efficiency and long-term sustainability in small ruminant production systems within arid environments.

This study characterized the non-traditional or "exotic" pets most frequently admitted to a referral center (Center for Medicine and Research in Wild Animals-CEMPAS) located in Botucatu, São Paulo state, Brazil, and identified the main reasons for admission according to affected body systems or sense organs. A retrospective review of medical records was performed over 11 years, and data were grouped into four vertebrate classes: reptiles, mammals, amphibians, and birds. From 2014 to 2019, bird admissions exceeded mammals (p = 0.0001), whereas no significant difference was observed from 2020 to 2024 (p = 0.625). Reptiles were the least represented, and no amphibians were recorded in any year. In the bird class (n = 961), cockatiels (Nymphicus hollandicus) were the most common species (47.76%), followed by domestic chickens (Gallus gallus domesticus) (15.19%), and blue-fronted Amazons (Amazona aestiva) (8.01%). The digestive, integumentary, and musculoskeletal systems were the most affected. The mammal class accounted for 882 admissions, with rabbits (Oryctolagus cuniculus) predominating (52.38%), followed by guinea pigs (Cavia porcellus) (17.57%), brown rats (Rattus norvegicus) (10.77%), and Syrian hamsters (Mesocricetus auratus) (6.00%). In these animals, digestive disorders were most common, followed by integumentary, musculoskeletal, and reproductive conditions. The reptile class accounted for 164 admissions, mainly tortoises (70.12%) and turtles (18.90%), with the integumentary, musculoskeletal, and digestive systems most frequently affected. Overall, birds and mammals were the most commonly admitted non-traditional or "exotic" pets, while the digestive and integumentary systems were the most frequently affected across species, emphasizing the value of regional epidemiological data for improving exotic animal veterinary care.

The gut microbiota plays a central role in poultry health and production performance, yet its response to intensive fattening protocols and postbiotic supplementation in geese remains poorly characterized. This study used 16S rRNA gene amplicon sequencing to profile ileal and caecal microbial communities from geese raised under two fattening protocols, with or without postbiotic supplementation, and assessed the effect of 24 h post-mortem chilling on apparent community composition. Fattening protocol was associated with the largest differences in gut microbial structure, producing significant shifts in beta diversity in both the ileum and the caecum (although protocol, age at slaughter, and duration of postbiotic exposure co-varied between cohorts and cannot be fully disentangled), accompanied by extensive taxon-level differences identified by LEfSe. Postbiotic supplementation did not significantly alter overall community structure under force-feeding conditions but produced a taxon-specific, trend-level shift in the caecum under restricted feeding, suggesting that its effect depends on the continuity of supplementation relative to slaughter. Alpha diversity did not differ significantly in the ileum, but caecal richness differed significantly between the G2 and G5 postbiotic-supplemented groups (Conover-Iman test, adjusted p < 0.05). The warm- and chilled-dissection groups differed in ileal but not caecal community composition (individual-animal variation cannot be separated from the effect of chilling in this comparison, as the two groups consisted of different birds), indicating that dissection timing is an important methodological variable in goose microbiome research. These findings highlight cohort- and protocol-related differences as key correlates of gut microbial composition in geese and provide a framework for optimizing postbiotic supplementation strategies and sampling standardization in waterfowl production.

In forest ecosystems where seed dispersal is predominantly mediated by scatter-hoarding rodents, sympatric plants compete for these limited dispersal services. This competition can drive niche differentiation, prompting the question of how ecologically similar species achieve coexistence. To address this, we conducted a seed provisioning experiment in the Ailao Mountains, Yunnan Province, China. We released 4500 tagged seeds from three congeneric species of stone oaks (Lithocarpus hancei, Lithocarpus xylocarpus, and Lithocarpus pachyphyllus; Fagaceae) to compare their seed dispersal effectiveness (SDE) and identify the divergent strategies that may facilitate their coexistence. Seeds of all three species were more likely to be removed than eaten in situ. Among the removed seeds, the proportion of cached versus eaten did not differ significantly among species. L. pachyphyllus exhibited both a higher seed removal rate and greater dispersal distances compared to L. xylocarpus and L. hancei. However, in contrast to its congeners, L. pachyphyllus seeds were more frequently dispersed to shrub microsites rather than open areas. Despite these contrasting dispersal patterns, the three species ultimately achieved statistically similar SDE. These results demonstrate that congeneric species can exploit rodent dispersal services in distinct ways while attaining equivalent dispersal effectiveness. This niche segregation in dispersal strategy represents a potential form of niche partitioning that could theoretically promote coexistence among ecologically similar species.

Heat events and nutritional stress threaten honey bee health, but how pollen substitute formulation shapes responses to acute heat remains unclear. Newly emerged Apis mellifera workers received three pollen substitute diets or two beebread-based reference diets for five days before exposure to 45 °C for 4 h. Expression of 12 genes related to nutrition, endocrine regulation, immunity, oxidative defense, and cellular stress was examined using mixed-effects and multivariate analyses. Immune-derived predicted biological age was estimated before and after heat exposure. Apparent consumption and survival were evaluated in an independent 18-day feeding assay without heat. Significant diet × heat interactions occurred for 10 genes, whereas tor and dome showed no significant interactions. At baseline, Diet2(M) exhibited a transcriptional profile similar to the control and a lower predicted biological age than Diet1(S) and Diet3(O). Diet2(M) also supported higher survival than Diet1(S), despite similar apparent consumption among substitute diets. These findings indicate that pollen substitute composition, rather than apparent consumption alone, can shape physiology and survival. Diet2(M) is therefore a priority candidate for colony-level evaluation, although improved heat tolerance was not demonstrated. These findings may guide the development of supplemental feeds supporting honey bee health under climate-related pollen scarcity and heat risk.

The current research investigated the effects of repeated mild handling stress (RMH) and acute handling stress (AHS) in male and female green mud crabs (Scylla paramamosain) on production, hemolymph biochemistry, immune system, antioxidant defense, endoplasmic reticulum stress gene expression, stress response, energy, and ion homeostasis. Gill, hepatopancreas, hemolymph, and muscle of 4 groups (F, M, F-RMH, and M-RMH) were sampled after 60 days of farming and after 27 h of AHS. No significant difference in growth performance and survival rate after 60 days was identified among the groups. Habituation in the M-RMH groups was observed (as shown by behavior change) and resulted in reduced fighting and broken legs. The lowest survival rate (9.09%) after AHS was observed in M crabs, which coincided with lower values of total protein in the gill, lysozyme, peroxidase, total antioxidant capacity, and glucose in the hemolymph, and higher levels of total amino acid, lactate dehydrogenase, sodium, and cholesterol in the hemolymph. Habituation may mitigate stress and aggression, which are significant issues in crab aquaculture.

Avian metapneumovirus (aMPV) is the main etiological agent of turkey rhinotracheitis, causing respiratory distress and economic losses in turkeys. While its impact in broilers and laying hens is relatively limited, aMPV subtype C (aMPV/C) is an important pathogen in ducks and waterfowl, leading to respiratory distress and severe egg-drop syndrome. To overcome the limitations of current diagnostics, such as heavy reliance on laboratory infrastructure and prolonged turnaround times, we established a rapid detection assay integrating recombinase polymerase amplification (RPA) with CRISPR/Cas12a and a lateral flow dipstick (LFD), targeting the conserved N gene of aMPV/C. Reaction parameters were systematically optimized, with 30 nmol/L Cas12a and 40 nmol/L crRNA identified as the optimal concentrations. Rigorous specificity evaluation against seven common avian pathogens revealed no cross-reactivity. The limit of detection (LOD) was determined to be as low as 1.3 × 10¹ copies/μL, outperforming conventional PCR. Validation using clinical samples demonstrated a 98.85% concordance rate with quantitative PCR (qPCR). This platform enables visual detection of aMPV/C within 1 h with minimal equipment requirements. Combining high sensitivity, absolute specificity, and operational simplicity, this assay shows promise as a practical tool for point-of-care diagnostics and epidemiological surveillance of aMPV/C.

Bosten Lake and Taitema Lake are important inland lakes in arid Northwest China, but recent fish-assemblage variation in these systems remains poorly resolved. We surveyed fish communities at 10 sites in Bosten Lake and four sites in Taitema Lake from 2023 to 2025 using standardized conventional capture methods. Across the three years, 20 species from 7 orders and 12 families were recorded in Bosten Lake and 12 species from 6 orders and 9 families in Taitema Lake; Cyprinidae was the most species-rich family in both lakes. The cumulative observed species pool and effort-standardized richness were higher in Bosten Lake, but year-specific site-level richness contrasts were not significant after Holm adjustment. Community composition differed between lakes after adjustment for year using exact whole-site permutations (Bray-Curtis PERMANOVA: pseudo-F1,38 = 37.92, partial R² = 0.499, p = 0.0010), although multivariate dispersion also differed (PERMDISP: F = 5.46, p = 0.030). Site-restricted PERMANOVA detected year effects in Bosten Lake (pseudo-F2,18 = 29.37, partial R² = 0.765, p < 0.001) and Taitema Lake (pseudo-F2,6 = 156.36, partial R² = 0.981, exact p = 0.0046). Bosten Lake had higher Margalef richness (Taitema minus Bosten: -0.818, 95% CI -1.451 to -0.185, p = 0.016) and Pielou evenness (-0.056, 95% CI -0.105 to -0.008, p = 0.027), whereas Shannon-Wiener diversity did not differ detectably between lakes (-0.169, 95% CI -0.673 to 0.335, p = 0.478). After controlling for site and year, no diversity-environment correlation remained significant after false-discovery-rate correction, and the partial RDA test of within-site temporal environmental-community covariation was nonsignificant (pseudo-F2,24 = 1.285, partial R² = 0.097, p = 0.1754). Thus, the study documents clear spatial separation between lakes and interannual variation within lakes, but does not identify the retained environmental variables as statistically robust drivers of those patterns.

Continuous environmental, production, locational, image, and acoustic data have increasingly been collected from laying-hen farms through precision livestock farming (PLF) systems. However, sensor-derived classifications have often been validated against human-assigned behavioral or appearance labels rather than independently measured physiological states. In this narrative review, the methodological requirements for using physiological indicators as reference labels in PLF models for laying hens were examined, considering blood biochemistry, corticosterone concentration, the heterophil-to-lymphocyte ratio, body temperature, and immune or disease indicators alongside structured farm-level data and unstructured video, thermal, and acoustic data. Direct sensor-to-reference comparison studies numbered only seven and predominantly used rectal or cloacal temperature, peripheral temperature, clinical trajectories, or disease outcomes. No study identified in this review developed and externally validated a composite label combining blood biochemistry, the heterophil-to-lymphocyte ratio, corticosterone, and immune or pathogen indicators in laying hens. Major barriers were considered to include sensor-biomarker time-scale mismatches, sampling-induced label noise, and inconsistent units of analysis across individual, flock, and farm levels. It is suggested that future studies incorporate individual identification, biomarker-specific temporal alignment, multimodal composite labeling, and independent farm-level validation, so that PLF for laying hens can progress from sensor-centered detection toward biologically validated decision support linked to management actions.

Load carriage is common during honey bee foraging, but its effects on the final approach to the hive remain unclear. We recorded one three-dimensional landing trajectory from each of 80 returning Apis mellifera foragers carrying fixed lead tags of 0, 20, 40, or 60 mg attached externally to the dorsal thorax (n = 21, 22, 16, and 21, respectively) using three high-speed cameras. We calculated a discrete estimate of trajectory curvature, flight velocity, and vertical velocity. The 20, 40, and 60 mg loads represented approximately 25.69%, 51.37%, and 77.06% of the mean body mass of a separate reference sample (n = 60), respectively. Control and 20 mg honey bees generally flew more slowly along more curved paths than 40 and 60 mg honey bees. The 40 mg group had the highest average velocity and lowest average curvature. In the 60 mg group, velocity and curvature varied among recording zones. These results show that landing trajectories differed among load treatments. However, the experimental loads differed from natural nectar or pollen loads, and without measurements of wing kinematics or flight forces, the observed trajectory differences do not identify a specific flight-control mechanism.