27 research outputs found

    BREEDING AND MOLT PATTERNS OF THE COMMON GROUND‐DOVE (COLUMBINA PASSERINA) IN XERIC, UNPREDICTABLE ENVIRONMENTS OF VENEZUELA

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    Abstract ∙ In non‐migratory birds the annual cycle is composed of two critical events, breeding and molt, spaced by quiescent periods. Breeding in arid environments is frequently dependent on rainfall, but arid environments have unpredictable and irregular precipitation; therefore, birds of arid environments are thought to maintain their reproductive system in a partially or fully activated state to responding rapidly to favorable conditions. Molt most commonly follows the end of reproduction. We studied the annual cycle of the Common Ground‐dove (Columbina passerina) for 15 months in arid scrub of Venezuela by determining gonadal sizes and maturation state, and by scoring wing, tail and body molt. As expected, both sexes underwent a brief period of gonadal regression of only about one month during the dry season, and maintained a partly or fully active reproductive system during the rest of the year. Breeding of Common Ground‐doves was associated to rainfall, but not exclusively so; testicular recrudescence began in advance of the rains and gonadal cycles of both sexes followed more closely the year’s precipitation rather than the long‐term rainfall pattern. Although birds maintained an extended period of reproductive readiness, they bred during limited periods; yet, differences in reproductive activity between the same months of consecutive years showed their temporal flexibility and opportunistic breeding. Common Ground‐doves molted throughout the year with no synchrony among individuals, replaced one primary per wing at a time, with no temporal overlap, and did not have a definite prebasic molt period of primary replacement. Lack of overlap in feather replacement would allow minimizing instantaneous energy and nutrient demands and lessening strain in birds that molt while breeding. Our results indicate that molt and breeding overlapped extensively at population and individual levels. Common Ground‐doves in xeric environments further illustrate the diversity of life histories of tropical birds in relation to ecological conditions.Resumen ∙ El patrón de reproducción y muda de la Tortolita Grisácea (Columbina passerina) en ambientes xéricos e impredecibles de Venezuela En aves no migratorias el ciclo anual se compone de dos eventos críticos, la reproducción y la muda, separados por períodos de quiescencia. La reproducción en ambientes áridos depende con frecuencia de las lluvias, pero los ambientes áridos tienen precipitación impredecible e irregular; por lo tanto, se considera que las aves de ambientes áridos mantienen su sistema reproductivo en un estado parcial o totalmente activado para responder rápidamente a condiciones favorables. La muda habitualmente ocurre al final de la reproducción. Estudiamos el ciclo anual de la Tortolita Grisácea (Columbina passerina) durante 15 meses en matorrales áridos de Venezuela mediante la determinación del tamaño y maduración de las gónadas, y el registro de la muda de alas, cola y cuerpo. De acuerdo a lo esperado, ambos sexos mostraron un breve período de regresión gonadal de alrededor de un mes durante la tempo‐ rada seca, y mantuvieron parcial o totalmente activado su sistema reproductivo durante el resto del año. La reproducción de la Tortolita Grisácea estuvo asociada con la lluvia pero no exclusivamente con esta; la recrudescencia testicular comenzó antes de las lluvias y los ciclos gonadales de ambos sexos siguieron más fielmente la precipitación del año de estudio que el patrón de lluvias a largo plazo. Aunque las aves mantuvieron un período prolongado de disposición a la reproducción, se reprodujeron durante períodos limitados. Sin embargo, las diferencias en la actividad reproductiva entre los mismos meses de años consecutivos demostraron la flexibilidad temporal y reproducción oportunista. Las Tortolitas Grisáceas mudaron durante todo el año sin sincronía, reemplazando una primaria por ala a la vez, sin solapamiento temporal y sin mostrar un período de muda prebásica definido de reemplazo de las primarias. La ausencia de solapamiento les permitiría minimizar las demandas instantáneas de energía de nutrientes y reducir el estrés en individuos que mudan mientras se reproducen. Nuestros resultados indicaron que la muda y la reproducción se superponen ampliamente tanto a nivel poblacional como individual. Las Tortolitas Grisáceas en ambientes xerófitos ilustran aún más la diversidad de historias de vida de las aves tropicales en relación con sus condiciones ecológicas

    Alta prevalencia de ADN de los helicobacteres no-H. pylori en la mucosa gástrica de perros domésticos venezolanos y sus alteraciones histopatológicas

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    Non-H. pylori helicobacters (NHPH) have been demonstrated as gastric spiral-shaped bacteria in specimens obtained from dogs; however, their roles in the pathogenesis of upper gastrointestinal disease have not yet been clearly established. The purpose of this study was to evaluate the prevalence of NHPH DNA in the gastric mucosa of dogs and its association with histopathology. Helicobacter was detected through histopathological techniques, PCR, and FISH analysis from fundic biopsies of twenty dogs with or without signs of gastrointestinal disease. PCR and FISH were based on partial 16S rRNA gene sequences. Nineteen dogs showed mild to marked gastritis in the fundus, and only one dog had a healthy gastric mucosa. NHPH DNA was detected in 18 dogs with gastritis and one with normal gastric mucosa. However, there was no significant correlation between the presence of NHPH DNA and the degree of gastritis. These results show a high prevalence of NHPH DNA in the gastric mucosa of dogs from Venezuela. Further studies are necessary to determine a possible association between a specific NHPH species and the degree of gastritis.Los helicobacteres no-H. pylori (NHPH, por sus siglas en inglés) han sido demostrados como bacterias gástricas de forma espiral; sin embargo, sus roles en la patogénesis de la enfermedad gastrointestinal superior no han sido claramente establecidos. El propósito de este estudio fue evaluar la prevalencia de ADN de los NHPH en la mucosa gástrica de perros y su asociación con histopatología. Helicobacter fue detectado a través de técnicas histopatológicas, análisis de PCR y FISH en biopsias del fundus gástrico de 20 perros con o sin signos de enfermedad gastrointestinal. La PCR y FISH se basaron en secuencias parciales del gen ARNr 16S. Diecinueve perros mostraron gastritis leve a marcada en el fundus gástrico y sólo un perro tuvo una mucosa gástrica sana. El ADN de los NHPH fue detectado en 18 perros con gastritis y uno con mucosa gástrica normal. Sin embargo, no hubo correlación significativa entre la presencia de ADN de los NHPH y el grado de gastritis. Estos resultados demuestran una alta prevalencia de ADN de los NHPH en la mucosa gástrica de perros de Venezuela. Futuros estudios son necesarios para determinar la posible asociación entre una especie específica de los HNPH y el grado de gastritis

    Occurrence of Proteus mirabilis associated with two species of venezuelan oysters

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    The fecal contamination of raw seafood by indicators and opportunistic pathogenic microorganisms represents a public health concern. The objective of this study was to investigate the presence of enteric bacteria colonizing oysters collected from a Venezuelan touristic area. Oyster samples were collected at the northwestern coast of Venezuela and local salinity, pH, temperature, and dissolved oxygen of seawater were recorded. Total and fecal coliforms were measured for the assessment of the microbiological quality of water and oysters, using the Multiple Tube Fermentation technique. Analyses were made using cultures and 16S rRNA gene sequencing. Diverse enrichment and selective culture methods were used to isolate enteric bacteria. We obtained pure cultures of Gram-negative straight rods with fimbriae from Isognomon alatus and Crassostrea rhizophorae. Our results show that P. mirabilis was predominant under our culture conditions. We confirmed the identity of the cultures by biochemical tests, 16S rRNA gene sequencing, and data analysis. Other enterobacteria such as Escherichia coli, Morganella morganii and Klebsiella pneumoniae were also isolated from seawater and oysters. The presence of pathogenic bacteria in oysters could have serious epidemiological implications and a potential human health risk associated with consumption of raw seafood.A contaminação fecal de frutos do mar crus por microrganismos oportunistas patogênicos representa problema de saúde pública. O objetivo deste estudo é investigar a presença de bactérias entéricas que colonizam ostras coletadas em área turística da Venezuela. Amostras de ostras foram coletadas na costa noroeste da Venezuela e foram registrados a salinidade local, pH, temperatura e o oxigênio dissolvido na água do mar. O total de coliformes fecais foi medido para a avaliação da qualidade microbiológica da água e das ostras, usando a técnica de fermentação em tubos múltiplos. Análises foram feitas usando culturas e seqüência do gene 16S rRNA. Enriquecimento diversificado e métodos de cultura seletivos foram usados para isolar a bactéria entérica. Obtivemos culturas puras de bastões retos Gram negativos com fímbrias de Isognomon alatus e Crassostrea rhizophorae. Nossos resultados mostram que P. mirabilis foi predominante nas nossas condições de cultura. Confirmamos a identidade das culturas por testes bioquímicos, seqüência do gene 16rRNA e a análise de dados. Outras enterobactérias como Escherichia coli, Morganella morganii e Klebsiella pneumoniae foram também isoladas da água do mar e ostras. A presença de bactérias patogênicas em ostras podem ter implicações epidemiológicas e potencial risco para a saúde humana quando do consumo de frutos do mar crus

    Connections : safe spaces for women and youth in Latin America and The Caribbean

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    RESUMEN: Este libro se puede leer en muchos niveles. Uno de ellos puede no ser muy obvio para aquellos que están acostumbrados a leer sobre violencia e inseguridad en América Latina. Es el nivel que le da a este libro un estatus de originalidad y una contribución que va más allá de la región: el ser una forma de conocimiento destinada no solo a interpretar el mundo, sino a cambiarlo […], visibiliza la importancia de un proceso de investigación ajustado al tipo de conocimiento que produce. Aquí se conectan el proceso y el resultado, lo que debería propiciar un debate más amplio con respecto a cómo y qué sabemos de la naturaleza de la violencia y la agencia social para reducirla […]. Esta visión es particularmente relevante en contextos donde el Estado reproduce la violencia, con terribles impactos, en especial en periferias excluidas. […] El proceso de investigación abordado en este libro transgredió muchas fronteras. Hubo fronteras entre países, barreras lingüísticas, fronteras en torno a la educación, el conocimiento y la experiencia, y entre etnias, géneros y generaciones. […] este proceso reunió a académicos, activistas y líderes comunitarios de cinco países de América Latina y uno del Caribe, incluyendo comunidades indígenas en México y Guatemala […]. La violencia está en el tiempo y en el espacio y se reproduce entre las generaciones en diversos espacios de socialización. Este proceso de investigación que trasciende las fronteras, plantea una discusión que atraviesa los diferentes casos sobre cómo los déficits y las desigualdades materiales, las violencias estatales en nombre de la ‘seguridad’, las especificidades culturales, de género y generacionales de la experiencia y la comprensión de la violencia, así como las diversas formas de criminalidad, se cruzan y se reproducen a través del tiempo y el espacio. Jenny Pearce, investigadora y profesora en el Latin American and Caribbean Centre (LACC) de la London School of Economics and Political ScienceABSTRACT: This book can be read on many levels. One level may not be so obvious to those who are used to reading about violence and insecurity in Latin America. It is the level which gives this book a claim to true originality and a contribution beyond the region. This contribution is to form of scholarship aimed not only to interpret the world but to change it […], this text visibilizes the significance of the research process to the kind of knowledge that is produced. It connects process and outcome, and this should start a wider debate about how as well as what we know about the nature of violence and the social agency to reduce it […]. This is particularly relevant in contexts where the State reproduces violence, with terrible impacts on the margins. The research process discussed in this book transgressed many boundaries. There were intercountry borders, linguistic barriers, boundaries around education, knowledge and experience and between ethnicities, genders and generations. […] the research process brought together scholars and community activists and actors from five Latin American and one Caribbean country. And within Latin America there were indigenous communities in Mexico and Guatemala who participated […]. Violence is located in time and space. It is reproduced inter-generationally through varied socialisation spaces. The boundary crossing research process, raises cross case discussion about how material deficits and inequalities, state violences in the name of ‘security’, cultural, gender and generational specificities of experience and understanding of violence, and varied forms of criminality, intersect and reproduce through time and space. Professor Jenny Pearce. Latin American and Caribbean Centre (LACC), London School of Economics and Political Scienc

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Dieta y eficiencia digestiva del Lechosero pechiblanco \u3cem\u3eSaltator orenocensis\u3c/em\u3e / Diet and digestive effi ciency of the Orinocan Saltator \u3cem\u3eSaltator orenocensis\u3c/em\u3e

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    El objetivo de este estudio fue realizar una descripción de los hábitos y las preferencias alimenticias del Lechosero pechiblanco Saltator orenocensis en los llanos de Venezuela, así como estimar la tasa de ingesta, la eficiencia digestiva y los tiempos de retención del alimento en cautiverio utilizando dos dietas artificiales. En cuanto a la dieta natural, esta ave se alimenta principalmente de frutas, maduras e inmaduras (47%), flores y yemas florales (29,8%) y hojas y yemas foliares (11,9%). Al analizar el presupuesto de tiempo, las aves pasaron la mayor parte del tiempo (cerca del 40%) en reposo y sólo pasaron entre un 8% y 13% del tiempo alimentándose. En cautiverio se demostró que S. orenocensis prefiere consumir frutas sobre hojas y hojas cultivadas sobre hojas silvestres. En el laboratorio, al ser alimentado con una dieta artificial a base de cambur, el Coeficiente de Energía Metabolizable (CEM) promedio (n=3) fue de 0,79 ± 0,02 y un tiempo medio de retención de 127 ± 5 min, con una tasa de ingesta diaria de 1,03 ± 0,10 veces su masa corporal. Estos valores fueron mayores que los reportados para aves frugívoras de masa corporal similar. Al suplementar la dieta artificial de cambur con hojas (20% en peso) observamos que el CEM promedio disminuyó (0,61 ± 0,01), sin embargo no se observaron diferencias significativas en la masa corporal, el tiempo medio de retención y la tasa de ingesta, indicando que la adición de hojas disminuyó la eficiencia digestiva de estas aves. La morfología del tracto digestivo de S. orenocensis es muy similar a la de otras aves frugívoras, sin embargo posee un pico cónico con bordes afilados que le permite cortar las hojas. Todas estas características indican que S. orenocensis es un ave parcialmente folívora que puede extraer nutrientes del contenido celular de las hojas. The main objective of this study was to describe the feeding habits and food preferences of the Orinocan Saltator Saltator orenocensis in the Venezuelan llanos, as well as to determine its rate of food intake, digestive efficiency and retention times of two artificial fruit-based diets in captivity. Regarding its natural diet, these birds feeds mainly on fruits, ripe and unripe (47%), flowers and flower buds (29.8%), and leaves and leaf buds (11.9%). Birds spent most of their time (circa 40%) resting, and spent only between 8% and 13% of their time feeding. Preference trials demonstrated that S. orenocensis prefered to consume fruits over leaves and cultivated leaves over wild leaves. In laboratory experiments, when fed a banana-based diet, S. orenocensis had a mean metabolizable energy coefficient (MEC) of 0.79 ± 0.02 (n=3), a mean digesta retention time of 127 ± 5 min, and a daily intake rate of 1.03 ± 0.10 times its body mass. These values are higher than those reported for other frugivorous birds of similar body mass. When the banana-based diet was supplemented with leaves (20%), the mean MEC decreased (0.61 ± 0.01), however, we did not observe significant differences in body mass, mean retention time and rate of food intake. The morphology of the digestive tract of S. orenocensis is very similar to that of other frugivorous birds, however, it has a conical beak with sharp edges, which allows birds to cut leaves in pieces. All of these characteristics indicate that S. orenocensis is a partially folivorous bird than can extract nutrients from the cellular content of leaves

    SURVIVAL, INDUCTION AND RESUSCITATION OF Vibrio cholerae FROM THE VIABLE BUT NON-CULTURABLE STATE IN THE SOUTHERN CARIBBEAN SEA

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    The causative agent of cholera, Vibrio cholerae, can enter into a viable but non-culturable (VBNC) state in response to unfavorable conditions. The aim of this study was to evaluate the in situ survival of V. cholerae in an aquatic environment of the Southern Caribbean Sea, and its induction and resuscitation from the VBNC state. V. cholerae non-O1, non-O139 was inoculated into diffusion chambers placed at the Cuare Wildlife Refuge, Venezuela, and monitored for plate, total and viable cells counts. At 119 days of exposure to the environment, the colony count was < 10 CFU/mL and a portion of the bacterial population entered the VBNC state. Additionally, the viability decreased two orders of magnitude and morphological changes occurred from rod to coccoid cells. Among the aquatic environmental variables, the salinity had negative correlation with the colony counts in the dry season. Resuscitation studies showed significant recovery of cell cultivability with spent media addition (p < 0.05). These results suggest that V. cholerae can persist in the VBNC state in this Caribbean environment and revert to a cultivable form under favorable conditions. The VBNC state might represent a critical step in cholera transmission in susceptible areas.El agente causal del cólera, Vibrio cholerae, puede entrar a un estado viable no cultivable (VNC) en respuesta a condiciones desfavorables. El objetivo de este estudio fue evaluar la supervivencia in situ de V. cholerae en un ambiente acuático al sur del Mar Caribe y su inducción y resucitación del estado VBNC. V. cholerae no-O1, no-O139 fue inoculado en cámaras de difusión ubicadas en el Refugio de Fauna Cuare, Venezuela, y monitoreado para contaje de colonias, células totales y viables. En 119 días de exposición al ambiente, el contaje de colonias fue < 10 UFC/mL y una fracción de la población bacteriana entró al estado VBNC. Adicionalmente, la viabilidad disminuyó dos órdenes de magnitud y ocurrieron cambios morfológicos de células bacilares a cocoides. Entre las variables del ambiente acuático, la salinidad presentó correlación negativa con el contaje de colonias. Los estudios de resucitación mostraron recuperación significativa de la cultivabilidad celular con adición de sobrenadantes de cultivos en crecimiento activo (p < 0.05). Estos resultados sugieren que V. cholerae puede persistir en estado VBNC en este ambiente de Caribe y revertir a una forma cultivable bajo condiciones favorables. El estado VBNC podría representar un paso crítico en la transmisión del cólera en áreas susceptibles
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