ARTHROPODS IN THE DIET OF THE BIRD ASSEMBLAGE FROM A FORESTED RURAL LANDSCAPE IN NORTHERN CHILOÉ ISLAND, CHILE: A QUANTITATIVE STUDY

Abstract ∙ Knowledge of bird diets is important to understand population fluctuations and the persistence of bird com‐ munities in changing landscapes. However, there is a general lack of quantitative information about the composition of bird diets at the community level in the Neotropics. Although consumption of fruits and seeds by birds has been well documented for forest ecosystems in southern South America, consumption of arthropods has received less attention, despite their relevance in bird diets. Here we describe and evaluate the presence and diversity of arthropods consumed by members of different dietary guilds of the avian community from temperate forests and rural land‐ scapes in northern Chiloé Island, Chile (42°S). We estimated the proportion of arthropods consumed by all bird species captured using mist nests in a mixed rural landscape, and identified arthropods at the order level, based on remains contained in bird droppings. In addition, we estimated trophic diversity for those bird species with the highest number of samples. Arthropod remains were prevalent in dropping contents for nearly all sampled species (17 out of 18 captured species), indicating that arthropod consumption is broadly distributed in the avian assemblage. The insectivorous Chilean swallow (Tachycineta leucopyga) had the highest average number of arthropods per sample but the lowest arthropod diversity. On the contrary, the highest arthropod diversity in droppings corresponded to the insectivorous House Wren (Troglodytes aedon). The omnivorous species, Austral Blackbird (Curaeus curaeus) and White‐ crested Elaenia (Elaenia albiceps) consumed mainly Coleoptera. Finally, arthropod orders found in droppings varied among bird species from the same and between dietary guilds. Resumen ∙ Artrópodos en la dieta del ensamble de aves que habitan el paisaje rural del norte de la Isla de Chiloé, Chile La información sobre los distintos componentes de la dieta de aves resulta relevante para entender las variaciones poblacionales y la subsistencia de comunidades ante la modificación del paisaje. Sin embargo, a la fecha, falta información cuantitativa sobre la composición de la dieta a nivel comunitario en el Neotrópico. A pesar de que el consumo de frutas y semillas por aves ha sido bien documentado para los ecosistemas templados del sur, el consumo de artrópodos ha recibido menos atención a pesar de su relevancia en la dieta de las aves. En este trabajo describimos y evaluamos la diversidad de artrópodos en la dieta de miembros de distintos gremios tróficos de la comunidad de aves de los bosques templados del sur de Sudamérica en el norte de la Isla de Chiloé, Chile (42°S). Para cada especie de ave capturada, estimamos la composición y la diversidad trófica de artrópodos en la dieta en base al análisis de heces. Registramos el consumo de artrópodos en 17 de las 18 especies capturadas, sugiriendo que el consumo de artrópodos está ampliamente distribuido en la comunidad de aves analizada. La Golondrina chilena (Tachycineta leucopyga), especie insectívora, tuvo el mayor número de artrópodos promedio por muestra y, a la vez, la menor diversidad de órdenes de artrópodos en su dieta. Por el contrario, el Chercán (Troglodytes aedon), especie insectívora, registró la mayor diversidad de artrópodos consumidos. Entre las especies omnívoras, tanto el Tordo (Curaeus curaeus) como el Fio‐fio (Elaenia albiceps), consumieron principalmente coleópteros. Finalmente, los órdenes de artrópodos registrados variaron entre aves pertenecientes al mismo gremio así como también entre distintos gremios tróficos.

Modificación al método de determinación de la concentración de espermatozoides en el semen ovino

Se comparan dos métodos para la concentración espermática en carneros. EI método modificado consiste en la obtención de 0.01 ml de semen con una micropipeta de dilución, el cual se mezcla con 3.99 ml de citrato de sodio

A review on coastal urban ecology: research gaps, challenges, and needs

Coastal urban areas have dramatically increased during the last decades, however, coastal research integrating the impacts and challenges facing urban areas is still scarce. To examine research advances and critical gaps, a review of the literature on coastal urban ecology was performed. Articles were selected following a structured decision tree and data were classified into study disciplines, approaches, type of analysis, main research objectives, and Pickett's paradigms in-, of-, and for- the city, among other categories. From a total of 237 publications, results show that most of the research comes from the USA, China, and Australia, and has been carried out mostly in large cities with populations between 1 and 5 million people. Focus has been placed on ecological studies, spatial and quantitative analysis and pollution in coastal urban areas. Most of the studies on urban ecology in coastal zones were developed at nearshore terrestrial environments and only 22.36% included the marine ecosystem. Urban ecological studies in coastal areas have mainly been carried out under the paradigm in the city with a focus on the disciplines of biology and ecology. Results suggest a series of disciplinary, geographical, and approach biases which can present a number of risks. Foremost among these is a lack of knowledge on social dimensions which can impact on sustainability. A key risk relates to the fact that lessons and recommendations of research are mainly from developed countries and large cities which might have different institutional, planning and cultural settings compared to developing and mid-income countries. Scientific research on coastal urban areas needs to diversify toward an ecology of and for the cities, in order to support coastal development in a diversity of countries and settings

Correlaciones entre circunferencia escrotal y algunas medidas zoométricas con el peso testicular en borregos pelibuey

EI trabajo se desarrolló con el objeto de correlacionar el peso testicular con la circunferencia escrotal y algunas medidas zoométricas

Influencia de la experiencia previa del recelador sobre la detección de calores en borregas pelibuey

EI trabajo se realizó en el Campo Experimental Mocochá (INIFAP) con el objeto de evaluar la eficiencia de hembras androgenizadas y machos con el pene desviado para detectar celos en borregas Pelibuey y comparar su eficacia cuando ambos son sometidos a u

Long term socio-ecological research of the three LTSER-Chile founder sites: challenges and opportunities for future research

This article presents an analysis of the research programs carried out in the three foundational sites of the Chilean Long-Term Socio-Ecological Research Network (LTSER-Chile) and presents the context in which these lines have been established

Immature Blood Vessels in Rheumatoid Synovium Are Selectively Depleted in Response to Anti-TNF Therapy

BACKGROUND:Angiogenesis is considered an important factor in the pathogenesis of Rheumatoid Arthritis (RA) where it has been proposed as a therapeutic target. In other settings, active angiogenesis is characterized by pathologic, immature vessels that lack periendothelial cells. We searched for the presence of immature vessels in RA synovium and analyzed the dynamics of synovial vasculature along the course of the disease, particularly after therapeutic response to TNF antagonists. METHODOLOGY/PRINCIPAL FINDINGS:Synovial arthroscopic biopsies from RA, osteoarthritis (OA) and normal controls were analyzed by double labeling of endothelium and pericytes/smooth muscle mural cells to identify and quantify mature/immature blood vessels. To analyze clinicopathological correlations, a cross-sectional study on 82 synovial biopsies from RA patients with variable disease duration and severity was performed. A longitudinal analysis was performed in 25 patients with active disease rebiopsied after anti-TNF-alpha therapy. We found that most RA synovial tissues contained a significant fraction of immature blood vessels lacking periendothelial coverage, whereas they were rare in OA, and inexistent in normal synovial tissues. Immature vessels were observed from the earliest phases of the disease but their presence or density was significantly increased in patients with longer disease duration, higher activity and severity, and stronger inflammatory cell infiltration. In patients that responded to anti-TNF-alpha therapy, immature vessels were selectively depleted. The mature vasculature was similarly expanded in early or late disease and unchanged by therapy. CONCLUSION/SIGNIFICANCE:RA synovium contains a significant fraction of neoangiogenic, immature blood vessels. Progression of the disease increases the presence and density of immature but not mature vessels and only immature vessels are depleted in response to anti-TNFalpha therapy. The different dynamics of the mature and immature vascular fractions has important implications for the development of anti-angiogenic interventions in RA

Wild floral visitors are more important than honeybees as pollinators of avocado crops

Wild insects provide pollination services in agroecosystems. Avocado is an economically important crop grown in the Chilean Mediterranean climate region and exported worldwide. Avocado pollination is managed using honeybee hives, while the role of wild insects as pollinators remains poorly known. We quantified the relative contributions of wild floral visitors and honeybees to the fruit set of avocados in two contrasting seasons (2015 and 2016) in Central Chile. Observations were made in 60 trees grown nearby (~300 m) to remnant patches of native sclerophyll vegetation. We found that honeybees and wild insects accounted for 48.6% and 51.4% of total floral visitation, respectively, with a 68% taxonomic similarity of floral visitors between seasons. The presence of honeybees significantly modulated the floral visitor composition and modified plant-pollination network parameters, which resulted in the biotic homogenization of the interaction network, through the increase of shared tree–floral visitor interactions, to the detriment of exclusive interactions. Finally, wild insects were more effective than honeybees in pollinating avocado trees and their contribution was greatest during the dry year. Thus, honeybees alone cannot be relied upon to deliver maximum pollination. We highlight ecological intensification practices to encourage wild insect visits and avoid native vegetation replacement with orchards. Therefore, we emphasize that future ecological intensification research should address agricultural practices to promote wild insects and evaluate the role of native vegetation as wild pollinator habitat in agricultural landscapes

Patients with rheumatoid arthritis in clinical remission and ultrasound-defined active synovitis exhibit higher disease activity and increased serum levels of angiogenic biomarkers.

INTRODUCTION: The aim of this study was to identify and characterize subclinical synovitis in patients with rheumatoid arthritis (RA) in clinical remission using power Doppler ultrasound (PDUS) and serum levels of biomarkers of inflammation and/or angiogenesis. METHODS: We selected patients with RA in clinical remission defined as a Disease activity score of 28 joints (DAS28)-erythrocyte sedimentation rate (ESR) <2.6 for more than six months tested by two independent rheumatologists. Clinical, epidemiological, demographic and serological data were analyzed. PDUS of knees and hands was performed by a sonographer. Synovial hypertrophy (SH) and PDUS signal were scored (grades 0 to 3). SH ≥2 and a PDUS signal was classified as active synovitis. Serum levels of biomarkers of inflammation/angiogenesis were determined by Quantibody Human Array. RESULTS: This study included 55 patients, of whom 25 (45.4%) met criteria for ultrasound-defined active synovitis. Patients with active synovitis had higher DAS28-C reactive protein (P = 0.023), DAS28-ESR (P = 0.06), simplified disease activity score, SDAI (P = 0.064), and only 12% were taking oral glucocorticoids (≤5 mg/day) compared with 40% of patients without active synovitis (P = 0.044). Patients with synovitis also had significantly higher serum levels of the angiogenic biomarkers angiopoietin-2 (P = 0.038), vascular endothelial growth factor-D (P = 0.018), placental growth factor (P = 0.043), stromal cell-derived factor-1 (P = 0.035), matrix metallopeptidase-2 (P = 0.027) and basic fibroblast growth factor (bFGF) (P = 0.007), but not of pro-inflammatory cytokines. CONCLUSIONS: Nearly half of the patients with RA in clinical remission had ultrasound-defined active synovitis, higher disease activity and less frequent oral glucocorticoid consumption than patients without active synovitis. This clinical situation was associated with a specific biological profile characterized by an excess of angiogenic mediators rather than persistent proinflammatory cytokine responses