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This study assessed the feasibility of contrast-enhanced ultrasound (CEUS) for evaluating renal perfusion in horses and compared perfusion parameters between age groups. In a prospective study, eight healthy horses were divided into young (3-5 years, n = 4) and old (16-17 years, n = 4) groups. All animals underwent B-mode, Doppler ultrasonography, and CEUS of the right kidney after an intravenous bolus of SonoVue (0.02 mL/kg). Qualitative analysis assessed contrast kinetics, whereas quantitative parameters (peak intensity, time to peak [TP], area under the curve, and wash-out time) were obtained from time-intensity curves in the renal cortex and medulla. The technique was safely performed in all horses, and the 0.02 mL/kg dose proved optimal for achieving adequate renal enhancement and consistent quantitative measurements. Quantitative analysis revealed a significantly longer TP in the renal cortex of older horses compared to young ones (p = 0.03), suggesting an age-related reduction in perfusion velocity. No other parameters showed significant differences. CEUS proved to be a feasible and safe method for assessing renal perfusion in horses. The prolonged cortical TP in older animals indicates that CEUS may be a sensitive tool for detecting early, subclinical perfusion changes associated with aging, warranting further investigation in horses with renal disease.
The gut microbiota produces molecules that trigger responses at the local and distant levels. It affects the brain through several metabolic products, including serotonin (5-HT). Tryptophan hydroxylase type 1 (Tph1) is the rate-limiting enzyme during 5-HT biosynthesis in the gut. Efavirenz (EFV), an antiretroviral agent against HIV, is associated with depression disorders and Tryptophan hydroxylase type 2 (Tph2) deregulation in mice. The possible association between the depressive effects of EFV secondary to dysbiosis and the expression of Tph1 in the intestine is yet to be studied. Therefore, we aimed to elucidate the role of the gut microbiota in depression mechanisms. We reviewed the gut microbiota, their metabolites (short-chain fatty acids [SCFA]), Tph1 expression in the gut, and systemic 5-HT and tryptophan levels in CD1 mice after 36 days of oral EFV (10 mg/kg) treatment. The proportions of Bacteroidota and Bacillota_A_368345 decreased and increased, respectively, following EFV treatment. Additionally, the abundance of Lactobacillus spp. and Faecalbaculum decreased, whereas that of Dubosiella spp., Blautia_A_141780, and Anaerostipes increased. These bacteria contribute to SCFA production and may have counteracted the lack of protective effects provided by Lactobacillus. Tph1 expression was dysregulated in the gut, whereas serum 5-HT levels decreased following EFV treatment. Lactobacillus species promote 5-HT production in the gut, and the deregulation of Tph1 affects 5-HT synthesis. This disruption in the gut-brain axis decreased peripheral 5-HT levels. This affects the serotonergic system in the brain, which could contribute to depression.
Platelet-rich gel supernatants (PRGS) are increasingly used in veterinary medicine due to their regenerative and immunomodulatory properties; however, most studies focus on individual mediators and provide limited insight into their coordinated biological behavior. This study aimed to characterize the integrated inflammatory-regenerative signatures of bovine PRGS stored under different temperature conditions using a multivariate approach. Concentrations of transforming growth factor beta-1 (TGF-β1), tumor necrosis factor alpha (TNF-α), interleukin-2 (IL-2), and interleukin-6 (IL-6) were evaluated in PRGS samples from six clinically healthy cows stored at -80, -20, 4, 21, and 37 °C for up to 326 h. Data were standardized and explored using hierarchical clustering and heatmaps, and principal component analysis (PCA) based on area under the concentration-time curve (AUC) was used to integrate temporal behavior. Temperature-dependent multivariate signatures were identified, with frozen PRGS clustering separately from samples stored at moderate temperatures. The first two principal components explained 43.0% and 28.9% of the variance and defined an inflammatory-regenerative gradient contrasting TGF-β1/IL-2 versus TNF-α/IL-6 profiles. Linear mixed-effects modeling showed that PC1 was significantly affected by temperature and time (p < 0.001), whereas PC2 was influenced by temperature, time, and their interaction (p ≤ 0.048). Differences among temperatures were minimal at early time points but became more pronounced from 48 to 96 h onward, following a temperature gradient with higher values at moderate temperatures and lower values under frozen conditions. These findings indicate that storage temperature reshapes the integrated biological profile of PRGS, rather than merely preserving mediator composition.
Understanding the dynamics of multihost pathogens, such as Mycobacterium tuberculosis complex (MTC), requires considering not only host interaction patterns but also variation in infectiousness across species. Network analysis is a useful tool to assess contact structure and disease risk, but it often depends on invasive methods. Camera trapping offers a noninvasive alternative to build co-occurrence networks in complex communities. In this study, we applied a novel approach that integrates shedding into ecological networks, weighing links between species pairs according to their co-occurrence frequency and shedding capacity, to evaluate tuberculosis (TB) risk across 18 study sites in the Iberian Peninsula. At the community level, TB risk was positively associated with mean strength-out, a local centrality measure of the frequency of interspecific contacts and their infectious potential. Species-specific models revealed that community TB risk increased with the strength-out of wild boar, red deer, and cattle, and with the closeness of red fox and badger. Furthermore, the community TB risk was jointly explained by shedding-weighted connectivity and spatial aggregation of wild boar, whereas red deer mainly contributed through their local abundance. In contrast, shedding-weighted centrality of badgers, foxes, and cattle explained TB risk, suggesting that ecological and management factors may influence TB spread. We defined epidemiological scenarios according to latitude, population factors, and infection pressure. These findings highlight the importance of including host infectiousness in ecological network analyses, as well as combining centrality measures and population data to understand and manage TB risk in complex host communities, with potential applications to other wildlife diseases and multihost systems.
The Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) is an important pathogen of the fall armyworm and is used as the basis for biological insecticides. In this study, we examined the relationship between the size-frequency distribution of SfMNPV occlusion bodies (OBs) and their insecticidal characteristics when collected at the end of the replication cycle. Exposure of OBs to 40%, 70%, and 90% (wt/wt) glycerol had no effect on OB pathogenicity. Glycerol density gradient (50-100%) centrifugation was used to separate OBs into two fractions. OBs recovered from the upper fraction of the gradient had a significantly smaller median cross-sectional area than those harvested from the lower fraction. These fractions also differed significantly in their size-frequency distributions. The OB concentration-mortality response of S. frugiperda second instars did not differ significantly between the two fractions or with non-centrifuged OBs. The median survival time was similar for insects inoculated with OBs from the upper and lower fractions but was significantly shorter in insects inoculated with non-centrifuged OBs. The proportion of mature OBs (67-71%) and the number of viral genome copies (1.33-1.40 × 108 copies/µL) did not differ significantly between the upper and lower OB fractions. These findings suggest that altering the size-frequency distribution by density gradient centrifugation is not a useful technique for selecting large OBs with high insecticidal activity as part of the baculovirus insecticide production process. Future studies should evaluate a range of OB size separation techniques to determine their effects on OB insecticidal characteristics.
In dairy production, Hermetia illucens oil (HIO) could represent a more sustainable energy source than oil palm products, but no in vivo information is available on the effects of this strategy on ruminal biohydrogenation and microbial-derived lipids [odd- and branched-chain fatty acids (FA) and dimethyl acetals (DMA)]. To address this knowledge gap, two balanced groups of 13 Valdostana Red Pied cows were fed a 70:30 forage-to-concentrate ratio diet, differing only for its supplemental lipid source: fractionated palm oil (FPO) or HIO (3.4% of concentrate dry matter). At the beginning and after 50 days of treatments, ruminal fluid was collected for a detailed characterization of lipids. Ruminal fluid of HIO cows showed a 25% decrease in total FA content relative to FPO, which might be explained by extensive ruminal disappearance of 12:0 (the main FA in HIO). Dietary HIO slightly reduced biohydrogenation completeness (-1.6%; P = 0.014) without favoring alterations that lead to the trans-10 pathway (e.g., without increasing trans-10 18:1/trans-11 18:1 ratio; P = 0.719). Just a few changes in ruminal FA composition appear to be explained by differences in FA intake (e.g., in 12:0 and 16:0; P < 0.001), whereas most variations would probably derive from an indirect effect of HIO promoting minor pathways of biohydrogenation and alternative metabolic processes, as supported by increases (P < 0.05) in the proportion of oxo-18:0 isomers and most BH intermediates with at least one double bond in Δ12 to Δ16 positions, compared with FPO. Changes in odd- and branched-chain FA and in DMA support that HIO affects ruminal FA profile through potential variations in ruminal microbial composition. The relative proportion of individual DMA was also modified, whereas total DMA content was not affected (P = 0.146). Overall, the minor effects of HIO on biohydrogenation, compared with FPO, supports the use of this alternative lipid source in dairy cow feeding. The oil extracted from black soldier fly (Hermetia illucens) larvae has recently emerged as a sustainable and innovative feed ingredient. Conventional fats are often included in the diets of dairy cows, but some of them are associated with negative environmental impact, such as those derived from oil palm cultivation. The aim of this study was to characterize the effects of replacing palm oil by black soldier fly oil on the lipid metabolism in the rumen of cows, which is a key aspect determining the digestion and subsequent utilization of lipids for milk fat production. Surprisingly, we observed a decrease in total fat content in the ruminal fluid of cows fed the black soldier fly oil, which was associated with an extensive disappearance of lauric acid (the most abundant fatty acid in the insect oil). The study of lipids that represent biomarkers of ruminal microbiota suggest possible changes in this microbial community, which may derive, at least in part, from the antimicrobial effect of lauric acid. Overall, our results suggest that H. illucens oil can be used in dairy cow diets without detrimental effects on ruminal lipid metabolism, as we observed only minimal changes in metabolic pathways compared to the use of palm oil, thus supporting its potential use as a sustainable feed ingredient.
Bovine dictyocaulosis, caused by Dictyocaulus viviparus, is a respiratory infection that leads to economic losses in livestock farming. The objective of this study was to compare two techniques for the diagnosis of D. viviparus. Residual fecal samples from routine diagnostics known to be positive were homogenized and subjected to the techniques proposed by modified Rugai, and Ueno techniques. We verified the effects of fecal refrigeration time (+24h and +48h), sedimentation time (2h and 12h), and water temperature (22°C and 46°C) on the recovery and sensitivity of first-stage larva (L1) diagnosis. Fecal refrigeration time (24h vs. 48h) did not significantly affect the number of recovered larvae, demonstrating that samples can be safely stored for up to two days. Room temperature water demonstrated a sensitivity below 75% in the recovery of D. viviparus during the first two hours in both techniques, increasing to 100% with 12 hours of sedimentation. However, heating the water to 46ºC proved to be the key factor: larval recovery became equal between the techniques, achieving 100% sensitivity in both after only two hours. We conclude that both techniques have similar sensitivity, making both valid for the recovery and diagnosis of D. viviparus.
Toxoplasma gondii and Neospora caninum are apicomplexan parasites infecting cattle, with implications for public health and livestock productivity, respectively. Since effective vaccines against these parasites are not currently available, identifying epidemiological factors associated with infection is important for improving control strategies. This study aimed to estimate the seroprevalence of both parasites and to identify factors associated with seropositivity in intensive dairy cattle in central Chile. A cross-sectional study was conducted using serum samples from 567 cattle, analyzed by ELISA. Epidemiological data were collected through semi-structured surveys, and associations with seropositivity were evaluated using multivariable logistic regression models, including mixed-effects models to account for farm-level clustering. Seroprevalence was 7.6% for T. gondii and 22.4% for N. caninum. For T. gondii, factors associated with seropositivity included older age categories (OR = 7.09; 11.25) and the presence of dogs in pens (OR = 6.07). For N. caninum, straw bedding use (OR = 5.13) and cat presence (OR = 6.32) were associated with higher odds of seropositivity. An additional association with lower N. caninum seropositivity was observed for BCG vaccination (OR = 0.24). These findings provide updated epidemiological data for dairy cattle in Chile. The association observed with BCG vaccination should be interpreted cautiously, as the study design does not permit causal inference.
Understanding temporal patterns of Leishmania infection in sand fly populations is essential for assessing transmission risk and improving surveillance and control in endemic regions. This study investigated infection dynamics in natural populations of Phlebotomus perniciosus and Phlebotomus ariasi, two established vectors of Leishmania infantum in the western Mediterranean and evaluated the utility of pooled sampling for vector surveillance. Sand flies were tested for Leishmania infection using a TaqMan real-time kinetoplast PCR either individually or in pools. Infection rates from pooled samples were estimated using maximum likelihood methods and analyzed alongside individual infection data using mixed-effects regression models to assess the influence of seasonality and female reproductive status on infection probability. Both individual and pooled analyses showed similar seasonal trends. Infection probability peaked in late summer, likely reflecting high parasite prevalence in reservoir hosts, and was highest in gravid females, suggesting cumulative parasite acquisition as sand flies age and complete successive gonotrophic cycles. Individual testing, although more resource-intensive, provided additional resolution by revealing species-specific patterns, with P. ariasi exhibiting higher infection rates than P. perniciosus, offering a deeper understanding of parasite circulation and species-specific infection patterns. We conclude that pooled sampling combined with appropriate statistical modelling can reliably capture seasonal infection patterns. Integrating reproductive status indicators with molecular surveillance represents a novel approach to refine transmission risk assessments and support more targeted and effective vector monitoring strategies in Leishmaniosis-endemic regions.
Canine ehrlichiosis, caused by Ehrlichia canis, is a tick-borne disease with a global distribution that significantly affects the clinical and epidemiological landscape for dogs. Although laboratory diagnosis is essential, current diagnostic methods exhibit limitations in sensitivity, specificity, and cost-effectiveness. This study evaluated the efficacy of ultraviolet (UV) spectroscopy combined with machine learning techniques to differentiate serological samples that are positive and negative for E. canis. A total of 46 canine serum samples, classified via Enzyme-Linked Immunosorbent Assay/Dot-Enzyme-Linked Immunosorbent Assay, were analyzed. Spectra (200-300 nm) underwent dimensionality reduction through principal component analysis, and classification using supervised algorithms, specifically support vector machine. In the binary classification of E. canis positive and negative sera, a linear SVM model (5 PCs) achieved 89.3% accuracy via Leave-One-Out Cross-Validation (LOOCV), yielding 85.7% sensitivity and 92.9% specificity. In the independent test set, the model reached 100% accuracy, sensitivity, and specificity, demonstrating high robustness and potential for diagnostic screening. The findings indicate that UV spectroscopy, in conjunction with machine learning, may serve as an effective complementary tool for diagnosing E. canis.
To describe a modified totally laparoscopic colonopexy technique performed using only two ports for the treatment of recurrent rectal prolapse in a cat, aimed at minimizing surgical access and postoperative morbidity. Case report. One adult feral domestic shorthair cat. A 3.4-kg adult male cat, with recurrent rectal prolapse following failure of conservative management, underwent a totally laparoscopic colonopexy using a two-port configuration. The procedure was performed through two 5-mm ports without colonic exteriorization. Serosal preparation of the descending colon and the left abdominal wall was achieved using monopolar electrocautery, followed by intracorporeal fixation with a continuous barbed polydioxanone suture. Surgical time, intraoperative findings, and postoperative outcome were recorded. Follow-up included clinical evaluation and abdominal ultrasonography. The procedure was completed without intraoperative complications, with a total surgical time of 43 min. Postoperative handling and medical management were limited due to the patient's aggressive behaviour. The cat resumed voluntary feeding within 6 h postoperatively and showed no signs of tenesmus or recurrence of rectal prolapse during short-term follow-up. Ultrasonographic evaluation at 30 days confirmed stable fibrous adhesion between the descending colon and the abdominal wall, with no evidence of recurrence or complications. A two-port totally laparoscopic colonopexy provided effective stabilization of the colon and successful resolution of recurrent rectal prolapse in this cat. This approach may represent a valuable minimally invasive alternative in selected feline patients, particularly those with behavioural limitations that restrict postoperative handling and medical management.
Arcobacter butzleri is an emerging zoonotic pathogen described in 1991. Despite its increasing incidence in clinical cases, there is still a need to better understand the underlying mechanisms of pathogenicity. Therefore, the aim of this study was to evaluate if different virulence profiles of A. butzleri are associated with different extent of virulence in the Galleria mellonella experimental model. Twenty-one A. butzleri strains isolated from various sources were characterized by searching for putative virulence determinants (PVDs) through genomic analysis and PCR (i.e., cadF, cj1349, ciaB, mviN, tlyA, pldA, irgA, hecA, hecB, and iroE genes). Seven virulence profiles were obtained (designated as Profile A to G). A representative strain from each profile was selected to conduct assays in the G. mellonella model. Even though the profile C was the most virulent, there was no correlation between the virulence profiles and G. mellonella mortality/melanization. Our study show that G. mellonella is a reliable and cost-effective model for studying the pathogenicity of A. butzleri. However, our results underscore the significance of evaluate additional virulence factors beyond the analyzed PVDs.
The response to the comment regarding our article is accurate: chronic consumption of a 6% Hibiscus sabdariffa Linnaeus (HSL) infusion for one month in healthy rats reduces reactive oxygen species (ROS) [...].
Canine leishmaniosis is an important vector-borne disease and a threat to dogs worldwide. Disease data are continuously being collected, with a consequent increase in the number of publications. This article provides practical guidelines for veterinary practitioners on the diagnosis, treatment, and prevention of leishmaniosis in dogs. These Canine Leishmaniosis Working Group (CLWG) recommendations aim to provide practical answers to the most common questions on the clinical management of this disease.
Bluetongue (BT) is an infectious, non-contagious, arthropod-borne viral disease of ruminants, and has a severe impact on livestock. It is caused by Bluetongue virus (BTV), a double-stranded (ds) RNA virus with a segmented genome (10 segments), belonging to the Seoreoviridae family, Orbivirus genus. Over the last 25 years, Europe has suffered multiple incursions of different BTV serotypes with serious consequences, which have mainly been controlled thanks to vaccination. In the case of Spain, from 2000 to 2023, BTV serotypes 1, 2, 4 and 8 have caused epidemics, and, sporadically, BTV-1 and -4 were detected in the same area and period. In 2024, BTV serotypes 1, 3 and 8 circulated simultaneously in the southwest of the country, causing a severe clinical impact in sheep but also in cattle and a multitude of outbreaks. Additionally, despite vaccination, serotype 4 also circulated that year, especially in areas where the other serotypes were already circulating. Whole-genome sequencing and phylogenetic analyses allowed us to confirm that serotypes 1 and 4 were homologous to viruses circulating in the country since 2000s, while serotypes 3 and 8 were homologous to BTVs recently notified in neighboring countries. In this context, many BTV co-infections of two or more different serotypes were confirmed by serotype-specific RT-PCRs, both in farms and individual animals. An epidemic caused by four serotypes coinciding in space and time had never occurred before in Spain, being a challenge for the diagnosis and control of this disease. Moreover, it could have favored the appearance of reassortant viruses with an unknown virulence, posing an additional risk. The data presented here raise the question of whether the co-circulation of different BTV strains, an exceptional situation, could become the new normal in certain areas of Europe.
Understanding how multiple physiological and ecological traits combine to shape functional profiles is essential for predicting how wild animals respond to environmental variability. We integrated morphological (body mass), trophic (δ1 3C, δ1 5N), and immune (hemagglutination, hemolysis) traits in nine passerine species sampled in summer and winter in central Chile to quantify multivariate functional profiles and assess their seasonal stability, phylogenetic structure, and environmental sensitivity. Principal component analysis identified three main axes of functional variation: a trophic-immune gradient (PC1), a body size-associated axis with secondary trophic contribution (PC2), and natural antibody-mediated immunity (PC3). Hierarchical clustering revealed a primary functional partition, whereas deeper subdivisions received limited bootstrap support, indicating that organization in functional space is better described as continuous trait gradients rather than discrete functional groups. Linear mixed-effects models using individual PC scores showed that seasonal shifts were most evident along PC1, whereas PC2 primarily reflected species-level differentiation associated with body size and dietary guild. PC3 exhibited moderate interspecific variation but limited seasonal responsiveness. Phylogenetic signal was not detected for any principal component axis, suggesting limited evidence for phylogenetic structuring of functional variation within this assemblage. Together, these results indicate that functional organization in these passerines reflects persistent species-level ecological strategies modulated by axis-specific seasonal plasticity. Integrating trophic and immune traits within a multivariate framework provides insight into how physiological differentiation and ecological specialization jointly shape community-level functional structure.
Haploid embryos constitute a valuable model for genetic and epigenetic studies; however, their developmental competence is reduced compared with diploid counterparts. This study evaluated whether supplementation of the culture medium with specific small molecules could improve developmental competence and outgrowth establishment of parthenogenetic haploid embryos. The effects of TGF-β inhibition (A83-01), WNT pathway modulation (CHIR99021 and IWR-1), and activin A (AA) supplementation were assessed from the morula stage onward under serum-free conditions. A83-01 treatment did not improve blastocyst formation or morphology and was associated with reduced total cell numbers relative to IVF controls. CHIR99021 supplementation increased the number of SOX2-positive cells compared with IWR-1 and vehicle-treated embryos, suggesting partial support of pluripotency; however, overall developmental progression remained inferior to diploid controls. In contrast, activin A significantly increased the proportion of haploid morulae developing into blastocysts and improved hatching rates. Nevertheless, AA supplementation did not restore CDX2-positive cell numbers or total cell counts to diploid levels. Furthermore, neither CHIR99021 nor AA affect DNA fragmentation levels, although a tendency toward increased TUNEL-positive cells was observed. Activin A treatment also failed to improve embryonic outgrowth formation. Collectively, these findings demonstrate that although activin A enhances blastocyst yield and hatching in bovine haploid embryos, modulation of TGF-β or WNT signaling alone is insufficient to restore diploid-like proliferative developmental competence.
Understanding the diversity of ticks is crucial to comprehending their population dynamics and role in pathogen transmission. Between July 2022 and July 2023, a total of 440 animals were inspected across 35 Cattle Production Units (CPU) adjacent to the Tamiahua and Tampamachoco lagoons in northern Veracruz, Mexico. A comprehensive total of 7,026 ticks, encompassing various developmental stages, were collected; this total includes 5,854 adults (83.3%), 984 nymphs (14%), and 188 larvae (2.7%). The prevalence of cattle infested with ticks was 93.7%, while in wild animals it was 50.9%. Morphological identification revealed the presence of eight species from three genera: Rhipicephalus microplus, Haemaphysalis leporispalustris, and six species of the genus Amblyomma (A. auricularium, A. dissimile, A. cf. tenellum, A. mixtum, A. ovale, and A. rotundatum). In wild animals, greater species richness was recorded with A. auricularium being the dominant species. In contrast, only two species were found in cattle. Interaction network analysis showed that A. mixtum has the highest number of associations with different hosts such as Bos taurus, Didelphis virginiana, Dasypus novemcinctus, Procyon lotor and Sylvilagus floridanus, while R. microplus was associated with Bos taurus and D. virginiana. These findings highlight the need to analyze not only species richness and abundance but also the potential for tick exchange among hosts and to correlate tick diversity with pathogen prevalence.
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