A high-resolution 13C NMR approach for profiling fatty acid unsaturation in lipid extracts and in live Caenorhabditiselegans.

Unsaturated fatty acids (UFA) play a crucial role in central cellular processes in animals, including membrane function, development, and disease. Disruptions in UFA homeostasis can contribute to the onset of metabolic, cardiovascular, and neurodegenerative disorders. Consequently, there is a high demand for analytical techniques to study lipid compositions in live cells and multicellular organisms. Conventional analysis of UFA compositions in cells, tissues, and organisms involves solvent extraction procedures coupled with analytical techniques such as gas chromatography, MS and/or NMR spectroscopy. As a nondestructive and nontargeted technique, NMR spectroscopy is uniquely capable of characterizing the chemical profiling of living cells and multicellular organisms. Here, we use NMR spectroscopy to analyze Caenorhabditis elegans, enabling the determination of their lipid compositions and fatty acid unsaturation levels both in cell-free lipid extracts and in vivo. The NMR spectra of lipid extracts from WT and fat-3 mutant C. elegans strains revealed notable differences due to the absence of Δ-6 fatty acid desaturase activity, including the lack of arachidonic and eicosapentaenoic acyl chains. Uniform 13C-isotope labeling and high-resolution 2D solution-state NMR of live worms confirmed these findings, indicating that the signals originated from fast-tumbling lipid molecules within lipid droplets. Overall, this strategy permits the analysis of lipid storage in intact worms and has enough resolution and sensitivity to identify differences between WT and mutant animals with impaired fatty acid desaturation. Our results establish methodological benchmarks for future investigations of fatty acid regulation in live C. elegans using NMR.

Lipidome and metabolome profiling of longissimus lumborum beef with different ultimate pH and postmortem aging.

The objective of this exploratory study was to assess the changes on lipidome and metabolome profiling of Longissimus lumborum bull muscle with different ultimate pH (pHu) and aging periods. The bull muscles classified as normal, intermediate, or high pHu were collected from a Brazilian commercial slaughterhouse, cut into steaks, individually vacuum-packaged, and aged for 3 days (3-d) or 21 days (21-d) at 2 °C. Muscle extracts were analyzed for the profiles of both lipids, by mass spectrometry (via direct flow-injection), and metabolites, by nuclear magnetic resonance, with downstream multivariate data analysis. As major results, pairwise comparisons identified C12:0 and C14:0 acylcarnitines as potential biomarkers of the intermediate pHu-muscle, which are related to lipid catabolism for alternative energy metabolism and indicate less protein breakage postmortem. Interestingly, the concentration of arginine at early postmortem aging (3-d) may influence the previously reported improved tenderness in normal and high pHu-muscles. Moreover, upregulation of fumarate, formate, and acetate with increased pHu muscle at 21-d aging indicate more intense tricarboxylic acid cycle, amino acid degradation, and pyruvate oxidation by reactive oxygen species, respectively. These three compounds (fumarate, formate, and acetate) discriminated statistically the muscle with high pHu at 21-d aging. The normal pHu-muscle showed higher concentrations of glycogenolysis and glycolysis metabolites, including glucose, mannose, and pyruvate. Hence, our results enhance knowledge of postmortem biochemical changes of beef within different pHu groups aged up to 21 days, which is essential to understand the mechanisms underpinning bull meat quality changes.

Moderate-intensity aerobic exercise training improves CD8+ tumor-infiltrating lymphocytes effector function by reducing mitochondrial loss.

Aerobic exercise training (AET) has emerged as a strategy to reduce cancer mortality, however, the mechanisms explaining AET on tumor development remain unclear. Tumors escape immune detection by generating immunosuppressive microenvironments and impaired T cell function, which is associated with T cell mitochondrial loss. AET improves mitochondrial content and function, thus we tested whether AET would modulate mitochondrial metabolism in tumor-infiltrating lymphocytes (TIL). Balb/c mice were subjected to a treadmill AET protocol prior to CT26 colon carcinoma cells injection and until tumor harvest. Tissue hypoxia, TIL infiltration and effector function, and mitochondrial content, morphology and function were evaluated. AET reduced tumor growth, improved survival, and decreased tumor hypoxia. An increased CD8+ TIL infiltration, IFN-γ and ATP production promoted by AET was correlated with reduced mitochondrial loss in these cells. Collectively, AET decreases tumor growth partially by increasing CD8+ TIL effector function through an improvement in their mitochondrial content and function.

Grape seed oil in the diet of primiparous Jersey cows before and after parturition: effects on performance, health, rumen environment, and milk quality.

The objective of the study was to determine whether adding grape seed oil (GSO) to the diet of primiparous Jersey breeds during the transition period would improve animal health by measuring effects on the rumen environment, serum biochemistry, oxidative response, and the composition and quality of milk. We used 14 Jersey heifers, weighing an average of 430 kg and 240 days of gestation. The animals were divided into two groups and offered a basal diet, including GSO in the concentrate for the GSO group (dose of 25 mL per animal day) and the same dose of soybean oil (SO) for the control group. The animals were allocated and maintained in a compost barn system, receiving an anionic diet (pre-partum) and a diet for postpartum lactating animals. Dry matter intake (DMI), milk production, serum biochemistry, serum and milk oxidative stability, ruminal fluid and milk fatty acid profile, milk qualitative aspects, and ruminal parameters such as pH, bacterial activity, and protozoan count were evaluated. The addition of GSO had a positive effect on the health of the cows, especially on the oxidative stability of the cows, by increasing total thiols (P = 0.03), higher plasma ferric reducing capacity (FRAP) (P = 0.01), and total antioxidant capacity (TAC) (P = 0.01). In the oxidative stability of the milk produced by the treated animals, there was also an increase in TAC (P = 0.05) and FRAP (P = 0.03). Discreet changes were observed in the ruminal environment with a decreasing trend in pH (P = 0.04) but an increase in bacterial activity (P = 0.05) and protozoa counts (P = 0.07) in cows that consumed the additive. GSO consumption affected the fatty acid profile in milk, increasing saturated fatty acids (SFA) (P = 0.05) and reducing unsaturated fatty acids (UFA) (P = 0.03). The oil did not affect milk production or efficiency in the postpartum period. Based on this information, it is concluded that the addition of GSO positively affects the cow's antioxidant system.

Development and assessment of a virtual escape-room game for teaching industrial bioprocesses.

This article presents a study on the implementation of a virtual escape-room game as a novel teaching methodology in biochemistry education. The game aimed to engage students in producing monoclonal antibodies against SARS-CoV-2 while reinforcing theoretical concepts and fostering teamwork. Three versions of the game were tested, incorporating modifications to address student feedback on and improve the overall experience. The study employed a satisfaction survey to gather insights from students regarding their perception of the game. Results showed that the implementation of answer flexibility using RegEx had a significant positive impact on student satisfaction and motivation. The introduction of RegEx allowed for a more realistic and immersive gaming experience, as students could provide varied answers while still being evaluated correctly. Overall, the findings highlight the effectiveness of the game's design, the suitability of the Google Forms platform for distance learning, and the importance of incorporating answer flexibility through RegEx. These results provide valuable guidance for educators seeking to enhance student engagement and satisfaction through the use of escape-room games in biochemistry education.

Fluid dynamics of life: exploring the physiology and importance of water in the critical illness.

Water acknowledged as a vital component for life and the universal solvent, is crucial for diverse physiological processes in the human body. While essential for survival, the human body lacks the capacity to produce water, emphasizing the need for regular ingestion to maintain a homeostatic environment. The human body, predominantly composed of water, exhibits remarkable biochemical properties, playing a pivotal role in processes such as protein transport, thermoregulation, the cell cycle, and acid­base balance. This review delves into comprehending the molecular characteristics of water and its interactions within the human body. The article offers valuable insights into the intricate relationship between water and critical illness. Through a comprehensive exploration, it seeks to enhance our understanding of water's pivotal role in sustaining overall human health.

Enhancing complex bioprocess learning through simulation technology and hybrid teaching: A case study in university education.

The utilization of computer simulators in university education is progressively being embraced to offer students a practical exposure to industrial bioprocesses. Bioreactor computer simulators hold various advantages over conventional laboratory experiments, such as cost-effectiveness and enhanced safety. The research objective is to assess the effectiveness of integrating bioreactor computer simulators into hybrid teaching to promote active and collaborative learning experiences and evaluate their impact on student participation and understanding. A hybrid strategy combining synchronous, face-to-face, and online teaching has been implemented to enhance the teaching-learning processes in the Industrial Bioprocesses course for Biochemistry students. The simulation software BIOSTAT®T Yeast was used. This software models the production of ethanol with Saccharomyces cerevisiae through batch cultivation and the determination of the kLa value of a bioreactor. In the first simulation activity, students analyzed the software response based on parameter values input by the instructor, while in the second simulation activity, students autonomously used the computer simulator under the primary oversight of the instructor. The survey results indicate that the pedagogical innovation was positively received and significantly motivating for the students. Comparing student satisfaction surveys between the two simulation activities suggests that fostering student autonomy and engagement through simulation technology can improve satisfaction and learning outcomes in bioprocess education.

Phytophotodermatitis From Lime Margaritas on a Mexico Vacation.

Phytophotodermatitis is a type of contact dermatitis that occurs upon skin exposure to certain plant chemicals, known as furocoumarins, along with simultaneous sun exposure. This case details a 34-year-old patient who presented to the office with an asymptomatic, irregularly shaped, and hyperpigmented patch located on the left inferior middle back that had been present since a recent beach vacation in Mexico. Upon gathering the history, clinicians should inquire about recent sunlight exposure while consuming and/or touching phytotoxic plant derivatives found in most citrus plants. The history should correspond with the skin examination findings and conclude that a cutaneous phytotoxic reaction had occurred when a lime margarita contacted the hand, which was subsequently rubbed onto the patient's back. This case highlights the importance of both taking a thorough history and physical examination and being aware of the broad range of skin manifestations to prevent unnecessary treatment, such as topical corticosteroids, for other skin disorders (the irregular presentation of atopic dermatitis, allergic contact dermatitis, and dermatitis unspecified) or improperly suspected child abuse in younger patient presentations.

The impact of enriched environments on cerebral oxidative balance in rodents: a systematic review of environmental variability effects.

Introduction: The present review aimed to systematically summarize the impacts of environmental enrichment (EE) on cerebral oxidative balance in rodents exposed to normal and unfavorable environmental conditions. Methods: In this systematic review, four databases were used: PubMed (830 articles), Scopus (126 articles), Embase (127 articles), and Science Direct (794 articles). Eligibility criteria were applied based on the Population, Intervention, Comparison, Outcomes, and Study (PICOS) strategy to reduce the risk of bias. The searches were carried out by two independent researchers; in case of disagreement, a third participant was requested. After the selection and inclusion of articles, data related to sample characteristics and the EE protocol (time of exposure to EE, number of animals, and size of the environment) were extracted, as well as data related to brain tissues and biomarkers of oxidative balance, including carbonyls, malondialdehyde, nitrotyrosine, oxygen-reactive species, and glutathione (reduced/oxidized). Results: A total of 1,877 articles were found in the four databases, of which 16 studies were included in this systematic review. The results showed that different EE protocols were able to produce a global increase in antioxidant capacity, both enzymatic and non-enzymatic, which are the main factors for the neuroprotective effects in the central nervous system (CNS) subjected to unfavorable conditions. Furthermore, it was possible to notice a slowdown in neural dysfunction associated with oxidative damage, especially in the prefrontal structure in mice. Discussion: In conclusion, EE protocols were determined to be valid tools for improving oxidative balance in the CNS. The global decrease in oxidative stress biomarkers indicates refinement in reactive oxygen species detoxification, triggering an improvement in the antioxidant network.

Using probiotics to improve nutrient digestibility and gut-health of weaned pigs: a comparison of maternal and nursery supplementation strategies.

Maternal probiotic supplementation has been found to have a positive impact on the gut health of piglets, not only during the lactation period, but also after weaning. Providing probiotics to nursery pigs is also a common strategy for supplementation. The goal of this study was to evaluate which would be the most effective strategy to improve nutrient digestibility, energy metabolism, and intestinal health in weaned pigs considering the maternal or nursery options. A total of 32 newly weaned pigs were randomly split into a 2 × 2 factorial arrangement considering maternal probiotic supplementation (with or without) in gestation-lactation and probiotic supplementation in the nursery period (with or without). After weaning, experimental diets were provided for 22 days. Total fecal and urine collection was performed from day 15 to 21. Blood samples were collected from all pigs on days 3 and 22 of the experiment to assess serum biochemistry and intestinal permeability. All pigs were euthanized on day 22 for intestinal tissue collection. Pigs born from probiotic-fed sows had greater (p < 0.05) total tract digestibility of dry matter (+1%) and gross energy (+1.3%), and greater (p < 0.05) metabolizable energy coefficient (+1.3%), which resulted in a 46 kcal/kg increase (p < 0.05) in the metabolizable energy content of the diet. Nitrogen intake (p = 0.035), uptake (p = 0.007), and retention (p = 0.012) were all increased in these pigs. Fecal moisture was reduced in pigs born from probiotic-fed sows and pigs fed the probiotic diet only in the nursery (p < 0.05). Pigs born from probiotic-fed sows had reduced intestinal permeability by 16% (p < 0.05), whereas pigs fed the probiotic diet in the nursery only tended to improve this response (p < 0.10). The villus:crypt ratio of pigs born from probiotic-fed sows was greater compared to the control (p < 0.05), while serum levels of alanine aminotransferase were lower (p < 0.05). Pigs born from probiotic-fed sows had increased nutrient digestibility and improved gut health. Therefore, it is concluded that supplementing the sow diets with probiotics rather than just providing diets in the nursery phase is an advantageous strategy.

Blood parameters and parasite burden in cattle with chronic fascioliasis.

Fascioliasis is a trematodiasis that affects domestic and wild animals as well as humans worldwide. It is a well-recognized disease in livestock, were it produces serious economic losses. Yet in cattle, there is limited information about the burden of liver flukes and its relation to the eggs per gram shed to the environment. There is also lack of knowledge on the effect of parasite load in blood parameters of infected animals, which is important to evaluate the severity and progression of the disease. The objective of this work was to gain insight in these aspects. Cattle from Mendoza province, Argentina, were inspected at a farm and at the abattoir determining the presence or absence of Fasciola hepatica. Each animal was sampled for blood and feces and in the slaughterhouse the livers were inspected. Hematology and blood chemistry parameters were determined, feces were examined for F. hepatica eggs by a quantitative sedimentation technique and livers were thoroughly inspected to determine the number of flukes. Infected cattle presented a mild burden of liver flukes per animal, strongly correlated (r = 0.72) to the number of eggs per gram of feces. The total number of eggs (X̄=35,100) shed per animal to the environment and the type of livestock management techniques in the region exacerbate the role of cattle as efficient reservoirs of this disease. Statistically significant lower red blood cell, lymphocyte and neutrophil counts were observed in infected compared to uninfected animals. All hepatic parameters tested showed highly statistically significant differences (p < 0.001) as well as proteins by cause of rise of globulins in infected cattle. The correlation between the amount of flukes in the liver and the number of eggs per gram of faces indicates coprology as a reliable and cost-effective method to infer parasite burden. The impact of fascioliasis on blood parameters can be of aid for the veterinary practitioner on the assessment of this disease on cattle.

Hematology and Serum Biochemistry of Coastal Seabirds Rehabilitated on the Southeastern and Southern Coast of Brazil.

Complete blood counts (n=566) and serum biochemistry (n=426) were assessed in seven coastal seabirds species that underwent rehabilitation along the southeastern and southern coast of Brazil from Saquarema, Rio de Janeiro State (22°56'16.44″S, 42°18'24.16″W) to Laguna, Santa Catarina State (28°29'43″S, 48°45'39.2″W), from August 2016 to August 2020. Blood samples were collected from four species of Charadriiformes, including Kelp Gull (Larus dominicanus, n=136), South American Tern (Sterna hirundinacea, n=25), Cabot's Tern (Thalasseus acuflavidus, n=17), and Common Tern (Sterna hirundo, n=14) as well as three species of Suliformes, the Brown Booby (Sula leucogaster, n=212), Magnificent Frigatebird (Fregata magnificens, n=104), and Neotropic Cormorant (Nannopterum brasilianum, n=58). The individuals were sampled as part of the protocol required before their release into the wild when considered healthy. This work aimed to establish the normal hematologic and biochemical reference values of those seabird species and, when possible, to analyze variations among age class and sex and to compare those with the available data in the literature. In addition, we provide the first baseline data for the South American Tern, Cabot's Tern, and Neotropic Cormorant. Baseline hematologic data are crucial for assessing health status of individuals and to support management and conservation actions, including release of seabirds into the wild.

Assessment of the effectiveness of an introductory general chemistry course in dentistry students enrolled in a biochemistry course.

As a strategy to carry out a better achievement in the Biochemistry course, undergraduate dentistry education manage a traditional course on the basic concepts of general chemistry necessary in the understanding of Biochemistry. In order to evaluate the effectiveness of learning outcome, we aimed to develop an evaluation tool that was applied to first-year dental students before and after receiving the general chemistry classes. Randomized trial consisted of 50 items distributed in 10 categories. The evaluation was applied to the students who took the Oral Biology course in the periods comprising 2020, 2021, and 2022 to a population of 109 students. Our results showed that after receiving the course the improvement rate was 20.71% with significant differences in each category. In conclusion, the introductory course allows students coming from different school systems to attend Biochemistry with similar knowledge of general chemistry.

On the significance of aspartate aminotransferase and creatine kinase in wild reptile health studies.

In reptile medicine, the enzymes aspartate aminotransferase (AST) and creatine kinase (CK) have been used in clinical diagnostics, where CK is considered an enzyme specific to muscle cell damage, while AST is a nonspecific enzyme that is mainly produced in the liver and muscle. When many native reptiles are sampled, it is evident that there are important differences between species and individuals belonging to the same species, making the AST and CK ranges very wide. The minimum and maximum values, variations and standard deviations were extracted for each enzyme from 17 wild reptile studies, revealing high variation and a wide range of variation for each species. AST and CK must be interpreted with caution in wild reptiles since there appears to be an important amount of individual and specific variation due to the muscular origin of these enzymes, and such variations tell us that there are considerable differences between individuals, physiological characteristics or sampling methods; thus, there is no apparent value derived from these kinds of studies on the utility of AST for evaluating liver damage, but the measurement of AST and CK can be useful for reptile health assessments or any manipulative study since they can eventually be used as indicators or potential biomarkers for restraint techniques or holding time.

Brazilin is a natural product inhibitor of the NLRP3 inflammasome.

Excessive or aberrant NLRP3 inflammasome activation has been implicated in the progression and initiation of many inflammatory conditions; however, currently no NLRP3 inflammasome inhibitors have been approved for therapeutic use in the clinic. Here we have identified that the natural product brazilin effectively inhibits both priming and activation of the NLRP3 inflammasome in cultured murine macrophages, a human iPSC microglial cell line and in a mouse model of acute peritoneal inflammation. Through computational modeling, we predict that brazilin can adopt a favorable binding pose within a site of the NLRP3 protein which is essential for its conformational activation. Our results not only encourage further evaluation of brazilin as a therapeutic agent for NLRP3-related inflammatory diseases, but also introduce this small-molecule as a promising scaffold structure for the development of derivative NLRP3 inhibitor compounds.

Perifoveal exudative vascular anomalous complex and resembling lesions treated with intravitreal triamcinolone.

PURPOSE: To report the use of intravitreal triamcinolone to treat macular edema associated with isolated perifoveal exudative vascular anomalous complex (PVAC) and resembling lesion (PVAC-RL). METHODS: In this case series, three diabetic patients (3 eyes) with PVAC-RLs and one healthy patient (1 eye) with PVAC lesion associated with cystic spaces underwent three intravitreal injections of aflibercept before switching to one intravitreal triamcinolone injection in each patient. RESULTS: Macular edema improved from 297.5 ± 8.10 µm, at baseline, to 269.2 ± 8.89 µm, after triamcinolone; whereas visual acuity improved from 20/38 to 20/26 (ETDRS). CONCLUSION: PVAC and PVAC-RL are rare and often misdiagnosed lesions that may be associated with decreased vision. Our outcomes suggest that intravitreal injection of triamcinolone may be an effective and affordable treatment for PVAC and PVAC-RL with intraretinal fluid.

A Brazilian case of exudative perifoveal vascular anomalous complex responsive to aflibercept intravitreal injections.

PURPOSE: To report a case of exudative perifoveal exudative vascular anomalous complex (ePVAC) in a Brazilian healthy patient that underwent a complete resolution after aflibercept intravitreal injections. CASE DESCRIPTION: A 41-year-old healthy Brazilian man complained of acute central vision loss in his right eye (RE). Fundus examination showed a perifoveal hemorrhagic aneurysmal lesion, accompanied by several hard exudates in RE. On fluorescein angiography, these abnormalities showed a progressive hyperfluorescence with surrounding leakage. Optical coherence tomography (OCT) revealed a deep, perifoveal hyporeflective cystic space with a hyperreflective wall and hyperreflective material inside of fibrin-like aspect. Around this aneurism, intraretinal hyporeflective spaces suggestive of exudation were detected. Nor pathological flow signal, or telangiectatic dilations were evidenced on OCT-angiography. Therefore, a diagnosis of exudative ePVAC in RE was hypothesized. After an initial observation, the patient underwent three monthly aflibercept intravitreal injections (0.05 ml/2 mg), with a significative anatomical and functional improvement after two weeks from first dose. On last follow-up at five months from baseline, patient experienced no evidence of new exudation and a stable visual acuity. DISCUSSION: Placental growth factor (PlGF) may impact on pericytes' dropout, and thus on ePVAC development. In contrast to the other anti-VEGF drugs, aflibercept is the only molecule contrasting PlGF. Therefore, aflibercept would act on ePVAC not as an anti-VEGF drug, but rather as an anti-PlGF one. CONCLUSION: This report encouraged the use of aflibercept as a therapeutic option for ePVAC. Further studies are required to confirm our result and the impact of PlGF on ePVAC pathogenesis.

Importance of three physiological models for teaching the carbohydrates metabolism.

In this work extensive misconceptions of university students' -from nutrition area- about the metabolism of carbohydrates (CHM) in the human organism have been documented. The results lead to consider their difficulties concerning the learning of a complex set of imbricated biochemical models involved. Pursuant to these considerations, three physiological models are proposed as conceptual axes around which CHM in the human organism could be taught, in order to avoid fragmentation in students' knowledge and to give simple physiological contexts where to integrate those biochemical models. These contexts are: (a) a physiological model of the carbon cycle, (b) a physiological model of blood glucose uptake and homeostasis, and (c) a physiological model of the availability of small metabolites.

Sublethal toxicity of carbofuran in cattle egret (Bubulcus ibis coromandus): hematological, biochemical, and histopathological alterations

Abstract This study was aimed to investigate Carbofuran (CF)-induced pathological changes in cattle egret. Two hundred cattle egrets were reared and equally divided into four groups and given different CF concentrations (0.03 mg/L, 0.02 mg/L, 0.01 mg/L and 0 mg/L (control group)). Hematology, serum biochemistry, histopathology, and immunological markers were studied. Our results confirm that CF induces anemic conditions, leukocytosis, elevated liver enzymatic activity, and alterations in renal biomarkers. Moreover, specific microscopic lesions such as multifocal necrosis, pyknotic nuclei, hemorrhages, congestion, and inflammatory cell proliferation were observed in the liver, kidney, spleen, and thymus. These findings suggest that CF can induce harmful effects, so the application of this pesticide in the field must be strictly monitored to mitigate the possibility of exposure to non-target species.

Resumo Este estudo teve como objetivo investigar as alterações patológicas induzidas por carbofurano (CF) em garças-vaqueiras. Duzentas dessas garças foram criadas e divididas igualmente em quatro grupos e receberam diferentes concentrações de CF: 0,03 mg/L; 0,02 mg/L; 0,01 mg/L; e 0 mg/L (grupo controle). Foram realizadas análises de hematologia, bioquímica sérica, histopatologia e marcadores imunológicos. Nossos resultados confirmaram que CF induz condições anêmicas, leucocitose, atividade enzimática hepática elevada e alterações nos biomarcadores renais. Além disso, lesões microscópicas específicas, como necrose multifocal, núcleos picnóticos, hemorragias, congestão e proliferação de células inflamatórias, foram observadas no fígado, rim, baço e timo. Esses achados sugerem que o CF pode causar efeitos nocivos, portanto a aplicação desse agrotóxico no campo deve ser rigorosamente monitorada para mitigar a possibilidade de exposição a espécies não alvo.

Clinico-pathological assessment of virulent Newcastle Disease Virus in ducks

Abstract Newcastle disease (ND) is an infectious, highly contagious and lethal disease of avian species. It is considered that ducks are natural reservoir or carrier for Newcastle disease virus (NDV) and are resistant against different strains of NDV. Current study was designed to evaluate the pathogenesis of Newcastle disease in domestic ducks through histopathology, immunohistochemistry (IHC) and serum biochemical changes. For this purpose, eighty ducks were reared for 42 days and divided in two groups A and B. Ducks in group A were challenged with (NDV) at rate of 0.1 ml of ELD50 (virus titer 107.32/100µl) on second week of age, whereas Group B was control negative. Splenomegaly, atrophy of thymus and necrotic lesion in kidney were observed on 9th day of post infection. Hepatic degeneration and mononuclear cell infiltration were noticed in proventriculus and intestine in challenged ducks. Viral antigen detected in lungs, intestine, proventriculus and lymphoid organs of infected ducks through IHC. Albumin and total protein values were significantly low in infected groups A as compared to control group B. ALT, AST, and ALP values were significantly high in infected group A. On 5th and 7th day of post infection oropharyngeal swabs were negative for NDV and cloacal swabs were positive for NDV through Reverse transcriptase polymerase chain reaction. It is concluded that ducks are susceptible to NDV and virulent strain of NDV caused disease in ducks.

Resumo A doença de Newcastle (DN) é uma doença infecciosa, altamente contagiosa e letal de espécies aviárias. Considera-se que os patos são reservatórios ou portadores naturais do vírus da doença de Newcastle (VDN) e são resistentes a diferentes cepas de VDN. O presente estudo foi desenvolvido para avaliar a patogênese da DN em patos domésticos por meio de histopatologia, imuno-histoquímica (IHQ) e alterações bioquímicas séricas. Para este propósito, 80 patos foram criados por 42 dias e divididos em dois grupos A e B. Os patos do grupo A foram submetidos ao VDN a uma taxa de 0,1 ml de ELD50 (título viral de 107,32 / 100 µl) na segunda semana de idade, enquanto o Grupo B foi controle negativo. Esplenomegalia, atrofia do timo e lesão necrótica no rim foram observadas no 9º dia pós-infecção. Degeneração hepática e infiltração de células mononucleares foram observadas no proventrículo e intestino em patos infectados. Antígeno viral foi detectado em pulmões, intestino, proventrículo e órgãos linfoides de patos infectados por IHQ. Os valores de albumina e proteína total foram significativamente baixos no grupo A infectado em comparação com o grupo B. Os valores de ALT, AST e ALP foram significativamente altos no grupo A. No 5º e no 7º dia após a infecção, os esfregaços orofaríngeos foram negativos para VDN, enquanto os esfregaços cloacais foram positivos para VDN por meio da reação em cadeia da polimerase via transcriptase reversa. Conclui-se que os patos são suscetíveis ao VDN e à cepa virulenta de VDN que causou doenças em patos.