Search Results (971)

Avian trichomonosis is caused by protozoa of the genus Trichomonas, mainly Trichomonas gallinae, which infects the upper digestive tract of birds and is commonly associated with Columbiformes, the main reservoirs of the parasite. This study aimed to investigate the occurrence and genetic diversity of Trichomonas spp. in captive synanthropic birds from southeastern Brazil. Oropharyngeal swabs were collected from 281 birds belonging to 13 avian orders and analyzed using Diamond medium culture, Giemsa-stained smears, and molecular assays. Of the 262 samples submitted to culture analysis, 72 (27.48%) showed trophozoite-like structures under light microscopy. Molecular screening based on the ITS1–5.8S–ITS2 region detected Trichomonas DNA in 76 out of 267 samples with successful DNA extraction (28.46%), including 72 Columba livia domestica from Franca, one Coragyps atratus from Ribeirão Preto, and three rock doves from Jaboticabal. Among the ITS-positive samples, 67 (88.15%) amplified the Fe-hydrogenase gene, and 65 (85.5%) were also positive for the 18S rRNA gene. Only six samples (2.29%) exhibited structures compatible with Trichomonas spp. in Giemsa-stained smears. Phylogenetic analyses based on ITS sequences grouped the isolates into two clades within the Trichomonas gallinae complex. Greater genetic diversity was observed using Fe-hydrogenase and 18S rRNA markers, revealing multiple haplotypes and clades. Molecular assays, particularly PCR applied directly to oropharyngeal swabs, showed higher sensitivity for detecting and characterizing Trichomonas gallinae compared to culture and cytology. These findings highlight the high occurrence and genetic diversity of T. gallinae in captive synanthropic pigeons and reinforce the importance of molecular tools for epidemiological surveillance in wildlife facilities. Full article

Haematopota pluvialis is a widely distributed hematophagic insect occurring across Eurasia. This horse fly may be a highly efficient mechanical vector of pathogens, including viruses, bacteria, and protozoa. Furthermore, its painful bites can cause local skin lesions and systemic symptoms. The aim of this study was to determine human exposure to H. pluvialis attacks in various types of open space habitats in Eastern Poland and to perform molecular screening of these tabanids for the presence of hematopathogens: Bartonella spp. and Anaplasma phagocytophilum. Specimens of H. pluvialis were collected at three distinct sites in Eastern Poland. The presence of Bartonella spp. and A. phagocytophilum was investigated using PCR-based methods. In total, 141 H. pluvialis females were analyzed. The molecular analysis of the rpoB gene fragment yielded one new haplotype of Bartonella sp. in 0.7% (1) of all studied samples, which may hypothetically exhibit zoonotic potential. Anaplasma phagocytophilum was not detected in the studied material. Moreover, a high level of human and animals exposure to horse fly bites was noted in the studied areas of Eastern Poland. The present results highlight the need for further targeted research on H. pluvialis to quantify pathogen prevalence, transmission efficiencies, and conditions facilitating pathogen transmission in natural settings. Full article

In order to assess the spreading of tick-borne bacteria and protozoa in a protected area largely frequented by people and in which numerous domestic and wild animals live, molecular analyses were carried out in ticks collected from fallow deer (Dama dama) to detect Anaplasma phagocytophilum, Borrelia sp., Coxiella burnetii, Francisella tularensis, Hepatozoon sp., and piroplasms. A total of 148 tick pools, for a total of 475 ticks collected from fallow deer and identified as female adult Ixodes ricinus, were submitted to DNA extraction and different PCR assays. One hundred and two (68.92%) pools were positive for one or more pathogens: three (2.02%) for C. burnetii, 21 (14.19%) for Borrelia sp., 35 (23.64%) for piroplasms, and 87 (58.78%) for A. phagocytophilum. All tick pools were negative for F. tularensis and Hepatozoon sp. Sixty-seven (45.27%) pools were positive for only one investigated pathogen, whereas in 35 (23.64%) pools DNA of two or more pathogens were found. Sequencing analyses identified 28 piroplasm amplicons as Theileria sp. OT3 and seven amplicons as possible Theileria cervi. Sequencing of the 21 Borrelia amplicons identified six samples as B. miyamotoi and eight as B. lusitaniae, whereas seven amplicons had 100% homology with a Borrelia sp. found in France and 99.37% with a B. theileri strain detected in Zambia. Monitoring tick-borne pathogens in ticks is pivotal to assess the spread of these microorganisms, the evolution of their epidemiology, and the risk of infections for animals and humans. Full article

A protozoa leads a rapid onset of symptoms, with high mortality rates in the rearing of the planktotrophic larvae of the tropical holothurian Isostichopus fuscus for aquaculture. This study aimed to determine the effect of temperature on the infection parameters and the larvae size with/without parasites in its five development stages: T1–EA (250–300 μm), T2–MA-I (300–600 μm), T3–MA-II (600–900 μm), T4–A (1.1–1.3 mm), and T5–LA (≈500 μm). Eight 500 L conical tanks with filtered and UV-sterilized seawater with 0.2 larvae mL⁻¹ under two temperature treatments (low: 23.0 ± 2.5 °C, high: 27.0 ± 0.5 °C). Thirty larvae per replicate at intervals of 4–5 days were sampled until day 25. A total of 1200 larvae were examined, and a total of 21,715 parasites were counted. A total of 97% of parasites were found under low temperature conditions. The DSI and survival significantly varied in relation to the temperature and time. The highest prevalence and intensity, 62.5 ± 5.7% and 130.5 ± 13.0, respectively, were observed at T4 at low temperature. At 18 d, larvae without parasites were larger (1494.1 ± 52.2 μm) than larvae with parasites (1237.7 ± 24.4 μm, p < 0.05) at 25 d. These findings suggest that elevated temperature functions as a key regulator in mitigating parasitic infections in auricularia larvae of I. fuscus. Full article

Few studies have investigated the effects of L-valine (L-Val) supplementation on in vitro rumen fermentation parameters and methane (CH₄) production in low-nitrogen diets for ruminants. Therefore, we examined the impact of L-Val supplementation in low-protein diets on in vitro rumen fermentation parameters, CH₄ production, and microbial community structure. Two crude protein (CP) levels and 4 L-Val levels were tested as follows: CON group (Control group with 14.05% CP), LD group (low-nitrogen diets with 11.26% CP), LVA group (LD group + 0.25% L-Val), LVB group (LD group + 0.5% L-Val), LVC group (LD group + 0.75% L-Val), and LVD group (LD group + 1% L-Val). The experiment was conducted at five time points (2 h, 4 h, 8 h, 12 h, 24 h), with three replicates per treatment at each time point. Results indicated the following: (1) Fermentation pH decreased overall with time; at each time point, the LVB group exhibited the highest pH, significantly higher than the LD, LVC, and LVD groups (p < 0.05). (2) Ammonia nitrogen (NH₃-N) concentration increased over time, with LVA~LVD groups showing higher levels than the LD group at 24 h, while showing no difference compared to the CON group (p > 0.05). (3) Microbial protein (MCP) trends aligned with NH₃-N, with the LVB group exhibiting higher MCP than the LD group, while showing no difference compared to the CON group (p > 0.05). (4) Compared to the LD group, adding 0.5~1% L-Val increased acetic acid, total VFA (TVFA), and isobutyric acid concentrations at 4 h, 8 h, and 24 h fermentation (p < 0.05). (5) The LVB group exhibited higher proportions of protozoa and Fibrobacter succinogenes (F. succinogenes) compared to the LD group (p < 0.05). The proportion of F. succinogenes showed no significant difference from the CON group (p > 0.05), while the proportion of Butyrivibrio fibrisolvens (B. fibrisolvens) decreased when L-Val addition exceeded 0.5%. (6) Correlation analysis revealed positive correlation between protozoa and TVFA (R = 0.512, p = 0.030). Isobutyric acid showed positive correlations with protozoa, B. fibrisolvens, and F. succinogenes (p < 0.05). In summary, under the present experimental conditions, the addition of 0.5% L-Val to a low-nitrogen diet did not affect predicted CH₄ production, but improved other in vitro rumen fermentation parameters, including acetate, isobutyrate and MCP. Meanwhile, it favored the growth and proliferation of the fibrolytic bacteria (B. fibrisolvens and F. succinogenes). This provides a theoretical basis for the rational formulation of low-nitrogen diets for sheep. Full article

Tick-borne protozoa (TBP), including Babesia spp. and Theileria spp., cause substantial health and productivity losses in cattle. In Thailand, most epidemiological studies have focused on dairy herds, while beef cattle remain underinvestigated. This study assessed TBP infections in beef cattle and their ticks at the Thai–Myanmar border. Blood samples were collected from 158 beef cattle, including local animals from Thong Pha Phum and Sangkhlaburi districts and cross-border cattle imported from Myanmar. Engorged ticks, predominantly Rhipicephalus microplus, were removed and identified morphologically. DNA was extracted from blood and tick samples, and PCR assays were performed to detect Babesia and Theileria species. Overall, 51.3% of cattle were positive for Babesia or Theileria DNA. Babesia bigemina (10.8%) and Babesia bovis (8.2%) were the most frequently detected species. Infection prevalence was higher in local cattle from Thong Pha Phum (56.0%) and Sangkhlaburi (54.6%) than in cross-border cattle (39.5%). In contrast, ticks collected from cross-border cattle showed a significantly higher prevalence of TBP DNA (40.0%) compared with ticks from Thong Pha Phum (12.8%) and Sangkhlaburi (8.7%). These findings provide important epidemiological evidence of TBP circulation at the Thai–Myanmar border and highlight the influence of cattle movement and tick exposure on pathogen distribution and spread in this region. Full article

Leishmaniasis is caused by parasitic protozoans of the Leishmania genus and has been classified as a Neglected Tropical Disease. Control of this parasite relies mainly on chemotherapy; however, conventional available drugs are unsatisfactory. Phytomedicine, particularly essential oils, is a promising alternative. In this study, the chemical composition and antileishmanial properties of essential oil from leaves of Schinus terebinthifolia Raddi (EO-St) were determined. Chemical components were identified by GC-MS. Antileishmanial activity on promastigotes of L. amazonensis was assayed, followed by the evaluation of the essential oil’s effects on the mitochondrial membrane potential and redox state of the parasite. Finally, the activity was confirmed on intracellular amastigotes and compared with cytotoxicity on peritoneal macrophages from BALB/c mice. In the essential oil, 78 compounds were identified. The major component was δ-3-carene with 14.8%. The IC₅₀ values of 18.2 ± 1.4 µg/mL and 15.0 ± 1.6 µg/mL against promastigote and amastigote forms, respectively, were obtained. The cytotoxicity for the host cells was approximately four-fold higher than those for the parasite. The essential oil was able to cause a disruption in the mitochondrial membrane potential. The quantified redox parameters showed statistical differences (p < 0.05) between EO-St-treated cultures and control groups (untreated and treated with DMSO). In summary, EO-St was active in vitro against both forms of L. amazonensis, possible mediated by mitochondrial dysfunction and redox imbalance. Full article

The leishmaniases are a group of neglected tropical diseases caused by kinetoplastid protozoa of the genus Leishmania, transmitted by phlebotomine sandflies. In the absence of a human vaccine, current chemotherapeutic options remain suboptimal due to limited target selectivity, high cost, restricted availability in endemic low-resource regions, and escalating parasite resistance. This review highlights recent advances in rational drug design directed at the kinetoplast—a distinctive mitochondrial organelle critical for parasite viability. Different targets (e.g., kDNA, G-quadruplex, topoisomerases) and innovative approaches employing mitochondrion-targeted small molecules are discussed, as well as ligand-functionalized nanoparticle delivery systems that can transport bioactive agents to the parasite’s mitochondrial microenvironment. These strategies highlight the kinetoplast’s strong translational relevance as a selective antileishmanial target. By exploiting its unique molecular machinery, these strategies may offer improved parasite selectivity, although potential mitochondrial liabilities in host cells must be carefully evaluated. Full article

Some parasitic infections promote or inhibit vascular growth in their hosts to increase parasite survival through immune evasion and tissue dissemination. This review focuses on how the most prevalent protozoan and helminth parasites in humans, such as Plasmodium, Toxoplasma, Leishmania, Trypanosoma, Entamoeba, Schistosoma, and Taenia, manipulate angiogenic pathways for their own benefit. This knowledge reveals that angiogenesis is central to the pathophysiology and therapeutic targeting of parasitic diseases. Importantly, parasites and/or their excretory/secretory factors, which modulate vascular responses, are potential treatments for chronic degenerative diseases in which angiogenesis is crucial to disease progression, such as cancer. Full article

As modern power markets integrate more renewable generation, day-ahead energy clearing remains the central procurement step, while flexibility products are procured to ensure that the cleared energy schedule can be operated securely. This paper proposes a closed-loop framework linking the Power Exchange (PX) and the Independent System Operator (ISO) to bridge energy-market settlement and network-feasible operation. The PX performs staged day-ahead clearing with energy settled first, followed by aAutomatic generation control (AGC) and spinning reserve (SR) procured from the residual headroom of committed (energy-awarded) units. The ISO then validates the cleared schedule using an equivalent current injection (ECI)-based screening. This paper uses a single-period (single-hour) IEEE 30-bus case setting; multi-period scheduling and intertemporal constraints are not modeled. When congestion is detected, power-flow tracing identifies the main contributors and guides a minimal-change redispatch. The ISO-feasible dispatch is then sent back to the PX for re-clearing, aligning prices and welfare with an executable operating point. The resulting nonconvex clearing problems with valve-point effects and prohibited operating zones are solved by Artificial Protozoa Optimizer with Social Learning (APO–SL) and evaluated against representative metaheuristic baselines. IEEE 30-bus studies show that off-peak and average-load cases pass ISO screening directly, whereas the peak case tightens reserve headroom (SR capped at 39.08 MW) and triggers congestion. After ISO feedback and energy re-clearing, line loadings return within limits. The ISO-feasible dispatch changes the marginal accepted offer and lifts the MCP (3.73 → 4.38 $/MWh). The welfare value reported here follows the paper’s settlement-based definition (purchase total minus accepted offer cost), and it increases accordingly (113.77 → 190.17 $/h). Full article

Tetrahymena pyriformis is biologically similar to Ichthyophthirius multifiliis, the parasite that causes “white spot disease” in fish. Because it has immune evasion genes and grows quickly, T. pyriformis serves as an ideal model for developing treatments against I. multifiliis and related parasites. This study tested water extracts from 10 traditional Chinese herbs against T. pyriformis and identified 5 with strong antiparasitic effects: Morus alba, Psoralea corylifolia, Sophora flavescens, Polygonum cuspidatum, and Pomegranate Peel. Combination tests showed that certain pairs, especially P. corylifolia with M. alba, worked together synergistically. When infected guppies were treated with this herbal combination at a concentration of 1.39 g/L (1:144 dilution), their 10-day survival rate reached 66.7%. Gill tissue analysis identified 577 genes with changed activity after treatment—228 increased and 349 decreased. These genes were linked to immune responses, metabolism, and cell processes. The key differentially expressed genes include those involved in the IL-17 signaling pathway, amino sugar metabolism, and the cytosolic DNA-sensing pathway. These results show that the herbal combination works by both directly killing parasites and boosting the fish’s immune system. This study provides a scientific basis for using natural herbal treatments as an eco-friendly way to control parasitic diseases in aquaculture. Full article

Cryptosporidium spp. and Giardia duodenalis are globally important intestinal protozoa causing diarrheal disease in humans and animals, with significant zoonotic potential. This study aimed to investigate the prevalence, molecular diversity, and potential transmission dynamics of these parasites in humans, livestock, and environmental samples from a rural community in Türkiye using a One Health approach, and to assess their associations with gut microbiome composition. Faecal samples were collected from 124 humans, 305 livestock (cattle, sheep, and goats), and 40 environmental samples (water and mud). Parasites were detected using qPCR and nested PCR, with positive samples genotyped by sequencing. Microbiome profiling was performed using 16S rRNA gene amplicon sequencing. Giardia duodenalis was detected in 12.1% of humans, 17.5% of livestock, and 2.5% of environmental samples, with assemblages A, B, and E identified, including the first detection of assemblage E in a human in Türkiye. Cryptosporidium spp. were found in 8.9% of humans, 19.3% of livestock, and 55% of environmental samples, with C. parvum as the dominant zoonotic species. Microbiome analysis revealed no significant differences in overall diversity. This study provides the first One Health assessment of Cryptosporidium spp. and Giardia duodenalis in Türkiye, emphasizing zoonotic transmission risks linked to livestock and the environment. Full article

To address critical issues in traditional quality control methods for discrete Euler solutions in underwater magnetic target detection—such as excessive filtering of valid solutions during divergence suppression, parameter settings reliant on subjective experience, and insufficient noise resistance—this study proposes a novel approach combining the Artificial Protozoa Optimizer (APO) with DBSCAN clustering. Based on the distribution characteristics of Euler solutions, an optimization objective function incorporating Euler solution residual penalty terms and contour line coefficients was constructed. The APO algorithm identifies DBSCAN clustering parameters that minimize this objective function, thereby enhancing clustering precision and accuracy. This method selects optimal Euler solution sets, enabling high-precision localization of magnetic targets. Simulation and field test results demonstrate that compared to statistical screening methods, the optimized algorithm achieves a 52.52% and 76.33% increase in the retention rate of valid solutions for noise-free and noisy data, respectively, while reducing the retention rate of invalid solutions by 28.57% and 94.21%. In field data, the average deviation from the true center of gravity is reduced by 28.06%. Full article

Giardia duodenalis, Enterocytozoon bieneusi, and Cryptosporidium spp. are common zoonotic intestinal protozoa in dairy goats, capable of cross-species transmission. These pathogens impair the growth and development of dairy goats and present a significant threat to public health. Conventional detection methods are time-consuming and lack sensitivity, requiring a rapid and efficient technique for simultaneous detection. A TaqMan probe-based multiplex real-time qPCR assay for the detection of the three protozoa was established in this study using specific primers and probes. Specificity validation demonstrated no cross-reactivity with other common intestinal pathogens of dairy goats. Sensitivity testing revealed minimum detection limits of 29.83, 39.33, and 33.15 copies/μL for the three protozoa, with excellent repeatability. Detection of clinical fecal samples and comparison with PCR confirmed the assay’s superior performance, which was capable of identifying positive samples missed by PCR. In conclusion, this rapid, specific, and sensitive assay provides technical support for large-scale epidemiological surveys and real-time monitoring of related protozoan diseases in dairy goats, thereby laying a scientific foundation for prevention and control and safeguarding both the dairy goat industry and public health. Full article

Despite the importance of wastewater environmental monitoring in disease prevention and response strategies, its use remains poorly documented in Senegal. In addition, there is more onsite sanitation than sewer networks in Dakar, and open drains channel for rainwater are also used as clandestine wastewater discharge into the sea. This study aimed to assess the presence of specific pathogens in wastewater, faecal sludge, and bathing water (the sea). Samples were taken at treatment plants, an open drain, and in the receiving environment (the sea) from June to December 2023. Total nucleic acid was subjected to multiplex qualitative qPCR using SeeGene Allplex™ kits targeting 34 gastrointestinal pathogens. Descriptive statistics, multiple correspondence analysis (MCA) and logistic regression were performed. Considering all matrices, across 51 analysed samples, the results revealed strong bacterial (96.08%, n = 49), parasitic (84.31%, n = 43), and viral (68.63%, n = 35) presence. These results showed high levels of Aeromonas spp. (96.08%), Blastocystis hominis (80.39%), Enterocytozoon (58.82%), and Norovirus GII (74.51%) among bacteria, protozoa, helminths, and viruses, respectively. Moreover, faecal sludge and pumping station samples show more identified pathogen than wastewater treatment plant and seawater samples. The MCA revealed that the dry season is spatially associated with a greater number of pathogens than the rainy season, but the latter showed a greater species diversity. Logistic regression showed that certain physicochemical parameters, including BOD5, turbidity, pH, and suspended solids, influence pathogen detection. However, qualitative detection and sampling period may constitute limitations. These results reveal that wastewater and bathing water can serve as sources of information on the circulation of pathogens of interest with epidemic potential. Therefore, this valuable epidemiological tool could serve as an adjunct to clinical surveillance in order to prevent future epidemics. Full article