28 research outputs found
Accidental poisoning with Wedelia glauca (“sunchillo”) in a bull confirmed by analysis of rumen content
Wedelia glauca is an invasive, perennial plant of the Asteraceae family native to South America. Its toxicity is attributed to the presence of a hepatotoxic terpenoid known as atractyloside, a powerful inhibitor of cellular respiration and ATP synthesis. Cattle are the most frequently poisoned species, and the course of this poisoning is hyperacute or acute. Occasionally, it is possible to find fragments of plants in the rumen contents and indentify the dermis structure of the plants, as they do not undergo significant changes in spite of the mechanic and enzymatic activities occurring in the rumen. The macroscopic and microscopic anatomopathologic findings of a natural Wedelia glauca poisoning case in a Hereford bull are reported. It was confirmed by micrographic analysis of plant fragments found in the rumen contents and also in bales used to feed those animals
A metaphylactic treatment with double dose oxytetracycline reduces the risk of bovine respiratory disease in feedlot calves
El objetivo del presente estudio fue evaluar el efecto del tratamiento metafiláctico con oxitetraciclina (OTC), a simple y doble dosis, en bovinos con alto riesgo de padecer enfermedad respiratoria bovina (ERB). El estudio se realizó en un establecimiento de engorde a corral donde se utilizaron 2.754 terneros que fueron considerados de alto riesgo de padecer ERB.
Se utilizó un diseño en bloque completamente al azar donde se consideró al animal como la unidad experimental y el corral (n=10) como bloque. Se formaron tres grupos experimentales: 1- control (CTL) el cual permaneció sin tratamiento, 2- recibió OTC 20 mg/kg SC (OTC20) y 3- recibió OTC 40 mg/kg SC (OTC40). El riesgo de ERB fue evaluado a través de una regresión logística. Los animales del grupo CTL tuvieron 2,85 y 7,14 veces más chances de enfermarse de ERB que los animales de los grupos OTC20 y OTC40 respectivamente (
Intoxicación por Cestrum parqui (“duraznillo negro”) en bovinos: confirmación por análisis micrográfico del contenido ruminal
En el reino vegetal existen numerosas especies hepatotóxicas para el ganado bovino, siendo la mayoría de las intoxicaciones de curso agudo a sub-agudo. Dentro de los vegetales hepatotóxicos agudos más conocidos en Argentina se encuentran: “duraznillo negro” (Cestrum parqui), “sunchillo” (Wedelia glauca), “abrojo grande” (Xanthium cavaniliensi) y “transparente” (Mioporum laetum). Cestrum parqui pertenece a las Solanáceas y en su composición química se ha demostrado la presencia de glicósidos, saponinas, y alcaloides responsables de los efectos tóxicos. El objetivo del presente trabajo fue presentar los hallazgos anatomopatológicos macroscópicos, microscópicos, hematológicos y el estudio micrográfico del contenido ruminal de muestras obtenidas de bovinos que ingirieron Cestrum Parqui en forma accidental. Vaquillonas cruza Abeerdeen Angus x Hereford fueron halladas muertas (n = 49) en un corral con buena oferta forrajera y abundantes plantas de “duraznillo negro”. Se tomaron muestras para análisis clínicos, estudios histopatológicos y análisis de contenido ruminal. Los resultados demostraron alteración de las enzimas hepáticas, reticulado tóxico en hígado y presencia de hojas de Cestrum parqui cuya identidad botánica se confirmó mediante micrografía. Esta última técnica constituye una herramienta complementaria diagnóstica útil para la confirmación de la intoxicación producida por esta planta hepatotóxica
Intoxicación accidental por paraíso (Melia azedarach) en bovinos
Fazzio, L.E.; Costa, E.F.; Streitenberger, N.; Pintos, M.E.; Quiroga, M.A.: Intoxicación accidental por paraíso (Melia azedarach) en bovinos. Rev. vet. 26: 1, 54-58, 201
Normal scaling in globally conserved interface-controlled coarsening of fractal clusters
Globally conserved interface-controlled coarsening of fractal clusters
exhibits dynamic scale invariance and normal scaling. This is demonstrated by a
numerical solution of the Ginzburg-Landau equation with a global conservation
law. The sharp-interface limit of this equation is volume preserving motion by
mean curvature. The scaled form of the correlation function has a power-law
tail accommodating the fractal initial condition. The coarsening length
exhibits normal scaling with time. Finally, shrinking of the fractal clusters
with time is observed. The difference between global and local conservation is
discussed.Comment: 4 pages, 3 eps figure
Effect of wearing a face mask on hand-to-face contact by children in a simulated school environment: the Back-to-School COVID-19 Simulation Randomized Clinical Trial
Importance Wearing a face mask in school can reduce SARS-CoV-2 transmission but it may also lead to increased hand-to-face contact, which in turn could increase infection risk through self-inoculation.
Objective To evaluate the effect of wearing a face mask on hand-to-face contact by children while at school.
Design, Setting, and Participants This prospective randomized clinical trial randomized students from junior kindergarten to grade 12 at 2 schools in Toronto, Ontario, Canada, during August 2020 in a 1:1 ratio to either a mask or control class during a 2-day school simulation. Classes were video recorded from 4 angles to accurately capture outcomes.
Interventions Participants in the mask arm were instructed to bring their own mask and wear it at all times. Students assigned to control classes were not required to mask at any time (grade 4 and lower) or in the classroom where physical distancing could be maintained (grade 5 and up).
Main Outcomes and Measures The primary outcome was the number of hand-to-face contacts per student per hour on day 2 of the simulation. Secondary outcomes included hand-to-mucosa contacts and hand-to-nonmucosa contacts. A mixed Poisson regression model was used to derive rate ratios (RRs), adjusted for age and sex with a random intercept for class with bootstrapped 95% CIs.
Results A total of 174 students underwent randomization and 171 students (mask group, 50.6% male; control group, 52.4% male) attended school on day 2. The rate of hand-to-face contacts did not differ significantly between the mask and the control groups (88.2 vs 88.7 events per student per hour; RR, 1.00; 95% CI, 0.78-1.28; P = >.99). When compared with the control group, the rate of hand-to-mucosa contacts was significantly lower in the mask group (RR, 0.12; 95% CI, 0.07-0.21), while the rate of hand-to-nonmucosa contacts was higher (RR, 1.40; 95% CI, 1.08-1.82).
Conclusions and Relevance In this clinical trial of simulated school attendance, hand-to-face contacts did not differ among students required to wear face masks vs students not required to wear face masks; however, hand-to-mucosa contracts were lower in the face mask group. This suggests that mask wearing is unlikely to increase infection risk through self-inoculation.
Trial Registration ClinicalTrials.gov Identifier: NCT0453125
Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial
Background: The EMPA KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population. Methods: EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110. Findings: Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5–2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62–0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16–1·59), representing a 50% (42–58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1). Interpretation: In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease. Funding: Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council
Senecio spp. transboundary introduction and expansion affecting cattle in Uruguay: clinico-pathological, epidemiological and genetic survey, and experimental intoxication with Senecio oxyphyllus.
AbstractThe genus Senecio is distributed worldwide, being responsible of poisoning in livestock and humans. Many species of Senecio have high invasion and expansion apacity, highly competitive with agricultural and native plant species, causing ecological damage. Particularly in Uruguay, poisoning by Senecio have grown exponentially to reach epidemic proportions. Herein we describe Seneciosis as a re-emerging and expanding epidemic disease affecting cattle, by describing clinico-pathological, epidemiological and genetic variation of species involved, as well as an experimental intoxication with Senecio oxyphyllus. For this, a study was carried out on 28 cattle farms in Eastern Uruguay, with history of seneciosis from 2010 to 2016. Plants of fifty populations of Senecio were sampled, in 2015 and 2016, for identification,analysis of alkaloids and study of genetic variation. In turn, post-mortem examination was performed in cattle of natural and an experimental case to confirm the intoxication, showing microscopic characteristic lesions (hepatomegalocytosis, diffuse fibrosis and ductal reaction). Four species of Senecio were identified: S. oxyphyllus, S. madagascariensis, S. selloi and S. brasiliensis. In the genetic study, 489 molecular markers of amplified sequencerelated polymorphisms (SRAP), associated with species and pasture, were used for genetic variation analysis. There was no statistically significant association between genetic variation determined by molecular markers and population (specimens of same species collected from the same farm), botanically determined species, or geographical origin. The increase ofseneciosis in cattle in the last years, the presence of species not identified to the moment with implication in the poisoning outbreaks and expansion of theseplants shows that the disease is in an epidemic growing active stage. In turn, the experimental poisoning with S. oxyphyllus confirms its chronic hepatotoxiceffect, being an emergent species for the region, of high distribution and toxic risk. This latter turned out the main Senecio species involved. This case of expansion of harmful plant for animal production and desirable plant species, can be useful as a model of ecopathological characterization, which is likely to occur with other toxic plants in different geographical ranges globally
Assessment of Plasma Zinc and Total Leukocyte Count in Calves Experimentally Infected with Mannheimia haemolytica
Mannheimia haemolytica is the main bacterial pathogen isolated in bovine respiratory disease (BRD), a common disease affecting calves before weaning. Previous research has shown that experimental infection with bovine herpesvirus 1, a respiratory virus, decreases plasma zinc (Zn) levels. However, changes in plasma Zn concentrations in calves experimentally infected with M. haemolytica have not been studied thus far. The objective of this study was to evaluate the effect of experimental infection with M. haemolytica on plasma Zn concentration in calves. Total leukocyte count and bovine respiratory disease (BRD) clinical score were also evaluated. We conducted a 6-day trial in 14 male Holstein calves randomly assigned to one of two groups, experimental (EG, n = 8) and control (CG, n = 6). Animals in EG were intrabronchially inoculated with M. haemolytica (6.5 × 106 CFU/mL) on day 0 of the trial. Plasma Zn levels were affected by time, treatment, and time by treatment interaction, being lower in EG compared with CG on days 1, 2, and 3. Differences in total leukocyte count were significant on day 1, observing a tendency on day 3. BRD clinical score differed between groups, being higher in EG throughout the trial. We conclude that experimental M. haemolytica infection reduced plasma Zn concentration in clinically ill calves, suggesting that the clinical condition of animals (healthy/ill) should be considered to better interpret plasma Zn values.Fil: Galarza, Esteban Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Lizarraga, Raúl Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; ArgentinaFil: Streitenberger, N.. Universidad Nacional de La Plata; ArgentinaFil: Arriaga, G.. Universidad Nacional de La Plata; ArgentinaFil: Abraham, G.. Universidad Nacional de La Plata; ArgentinaFil: Mattioli, Guillermo Alberto. Universidad Nacional de La Plata; ArgentinaFil: Anchordoquy, Juan Mateo. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; ArgentinaFil: Fazzio, Luis Emilio. Universidad Nacional de La Plata; Argentin
Complejo respiratorio bovino: evidencia de circulación viral múltiple en un establecimiento de cría
El complejo respiratorio bovino (CRB) es una de las principales causas de pérdidas productivas en rodeos de cría, tambo y engorde a corral. Los agentes infecciosos involucrados incluyen virus, bacterias y micoplasmas. Dentro de los agentes virales se encuentran el virus respiratorio sincicial bovino (bRSV), el virus parainfluenza 3 bovino (BPIV3), el herpesvirus bovino tipo 1 (BoHV1) y el virus de la diarrea viral bovina (BVDV). El objetivo de este trabajo fue evaluar la circulación de los virus asociados al CRB en un rodeo de cría, durante el período posdestete, mediante un estudio serológico longitudinal. En forma complementaria, se describieron y compararon los hallazgos clínicos y hematológicos. Se seleccionaron 32 animales de 5 a 7 meses de edad, sin vacunación previa, y se evaluó diariamente la presencia de signos clínicos compatibles con CRB. Se extrajeron muestras de sangre los días 0 (destete), +14 y +25 (momento en que culminó el ensayo). No se detectaron animales con manifestación clínica de CRB y los parámetros hematológicos se encontraron dentro del rango de referencia. Al inicio de la experiencia, ningún animal presentaba anticuerpos (Ac) específicos para bRSV, mientras que para el resto de los agentes virales, el porcentaje de animales seropositivos fue variable: 53% (BVDV1a), 31% (BPIV3), 25% (BVDV2) y 13% (BoHV1). Al día +25 los porcentajes de seropositivos fueron los siguientes: 47% (BVDV1a), 50% (BPIV3), 19% (BVDV2), 25% (BoHV1) y 81% (bSRV). Los porcentajes de seroconversión para bRSV, BPIV3, BVDV1a y BoHV1 fueron 34%, 25%, 16% y 13%, respectivamente. Además, el 66% de los animales seroconvirtió a uno o más virus. Para BVDV2 y BVDV1b no se observó seroconversión. Estos resultados evidencian la circulación, e incluso en algunos casos la coinfección de los agentes virales involucrados en el CRB en e período posdestete. Resulta importante la realización de estudios virológicos complementarios que permitan identificar y caracterizar las cepas circulantes en esta etapa productiva, principalmente en relación con bSRV y PIV3, virus de los que se posee escasa información en nuestro medio