Browsing by Author "Russo, Paulo"
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- Investigação em apicultura em Portugal: Portugal, apicultura e NosemaPublication . Pires, Sancia; Murilhas, António; Russo, Paulo; Valério, Maria JoséA Nosemose é uma doença das abelhas melíferas (Apis mellijera L.), cujo agente etiológico tradicional, (o microsporídio unicelular Nosema apis Zander), foi identificado há cerca de cem anos (Paxton, 2010). Considerada uma das patologias mais predominante e prejudicial para as abelhas ocidentais, tem sido intensamente estudada (apesar de nem sempre ser evidente, face a uma sintomatologia relativamente inaparente ou inespecífica). O Nosema upis (Na) pode originar grave desnutrição nas abelhas adultas e conduzi-las à morte. Todavia, em condições "normais", raramente provoca a morte das colónias infetadas (Fries, 1993, 1997; Paxton, 2010). Até ao início da década de 90, o Na foi considerado o único agente causal da Nosemose em colónias de abelhas europeias (Klec et al., 2007).
- La microscopía óptica y el estado del arte de la nosemosis en PortugalPublication . Pires, Sancia; Murilhas, António; Russo, Paulo; Valério, Maria JoséLa utilización de la microscópica óptica ha representado un papel importante en las ciencias de la naturaleza y continua siendo una técnica importante en innumerables áreas de la ciência. En Portugal, el estado sanitario en el campo apícola se rastrea mayoritariamente con este tipo de metodología. En los últimos años se ha contrastado un creciente número de casos positivos de Nosema, muchos de ellos comprobados en laboratorio (Laboratorio Nacional de Investigación Veterinaria y por el de Patología Apícola de la ESAB/AAPMN). En este trabajo se destaca la aportación de la microscópica óptica para el esclarecimiento de aspectos fundamentales del actual conocimiento de la patología, patogenia y etiología de la Nosemosis a nivel del territorio continental português. Las técnicas de diagnóstico de rutina (determinación de presencia y/o ausencia de esporas de Nosema y su recuento) adoptadas por los laboratorios nacionales se basan en la metodología recomendada por la OIE (2008). Básicamente consisten en la preparación del macerado de 60 abdómenes de abejas, de las cuales se retira una gota para un análisis microscópico en cámara de Neubauer(400x); las esporas se destacan como corpúsculos ovoides, refringentes, brillantes y envueltos en una membrana oscura.
- La microscopía óptica y el estado del arte de la nosemosis en PortugalPublication . Pires, Sancia; Murilhas, António; Russo, Paulo; Valério, Maria JoséLa utilización de la microscópica óptica ha representado un papel importante en las ciencias de la naturaleza y continua siendo una técnica importante en innumerables áreas de la ciencia. En Portugal, el estado sanitario en el campo apícola se rastrea mayoritariamente con este tipo de metodología. En los últimos años se ha contrastado un creciente número de casos positivos de Nosema, muchos de ellos comprobados en laboratorio (Laboratorio Nacional de Investigación Veterinaria y por el de Patología Apícola de la ESAB/AAPMN). En este trabajo se destaca la aportación de la microscópica óptica para el esclarecimiento de aspectos fundamentales del actual conocimiento de la patología, patogenia y etiología de la Nosemosis a nivel del territorio continental português.
- Main reasons for honey bee colony mortality in Portugal. A snapshot of beekeepers' beliefsPublication . Pires, Sancia; Murilhas, António; Russo, Paulo; Valério, Maria José; Gonçalves, ManuelTo investigate claims of abnormally high honey bee colony mortality in Portugal during 2011, a survey was carried out via telephone interviews. It included 662 (≈ 4%) registered Portuguese beekeepers and followed the basic 'Coloss' questionnaire. Interviewees were selected accounting for total numbers of colonies and the geographical distribution of their apiaries across the country. The 'sampling grid' was set to 5 beekeepers per county, fully covering continental Portugal and jointly considering the autumn and winter periods. The overall annual colony mortality that beekeepers historically regard as 'natural' for their own apiaries is 9.7 ± 0.2 (mean ± standard error of the mean), not significantly deviating from the 10.8 ± 0.2 they consider 'normal' for the wider region where their apiaries are located. Over the combined autumn and winter seasons, the initial number of interviewees' productive colonies (99428) decreased 3.6% (i.e. 3591). Furthermore, if the comparison is made with the total number of productive colonies existing in early spring of the previous year (93841), an increase of 2.1% was observed in April 2011. Although incorporating a considerable commitment to colony splitting and swarm captures, this increase is still surprising given the outcome of a nation wide survey focused on Nosema ceranae (showing that 51% of the 277 sampled apiaries across the country were infected by this microsporidian). It also demonstrates that the media hype generated around 'unexplained high colony mortality' occurring in Portugal was clearly unwarranted. When beekeepers were individually asked to provide their views on the main causes for the colony mortalities observed, albeit the regional variations, Varroa destructor was flagged (by 25% of them) as the key problem they are faced with in terms of colony survival. 'Poor quality' queens (mentioned by 13%), colony starvation (indicated by 12%), colonies overwintering in 'weak conditions' (pointed out by 11%) and 'nosemosis' (suspected by 4%) are other considerable sources of problems encountered. Twenty seven percent of the participating beekeepers also additionally singly brought up an extra difficulty from a residual group of additional 'relevant challenges' posed by wasps, ants, chalkbrood, American foulbrood, bee-eaters, pesticide intoxications or thymol application induced accidents.
- Main reasons for honey bee colony mortality in Portugal. A snapshot of beekeepers' beliefsPublication . Pires, Sancia; Murilhas, António; Russo, Paulo; Valério, Maria José; Gonçalves, ManuelSince winter 2006, extensive honey bee colony losses with distinctive features were first reported in the USA ( ‘Colony Collapse Disorder’, CCD). Global research over the past few years attempting to pin point CCD’s most likely causes, recurrently pointed out that no single factor is universally responsible for this disorder. Nevertheless, stressors e.g. the Varroa mite, some ‘new generation’ pesticides, an ever expanding ‘pathosphere’ affecting European Apis mellifera strains (just to name a few) and their multiple interactions with other long ongoing stress sources clearly compromise the multi‐level immune defense of honey bees, disrupting their social system and leading colonies to collapse. In Spain, various reports have suggested that Nosema ceranae is the main culprit regarding the abnormally high colony mortality levels reported. In Portugal, no reliable information existed (other than a few discrete anecdotal reports) on honey bee colony mortality levels across the beekeeping regions of the country, nor their ‘perceived’ causes. As a result, we carried out this work focusing on narrowing this knowledge gap by getting an overview of our beekeepers opinions. This study appears in the context of a project submitted by FNAP Measure 6A National Beekeeping Program (under EU Regulations No. 917/2004, No. 797/2004 and No. 1234/2007), in partnership with research institutions of the authors, under coordination of Prof. Sância Pires.
- Nosema distribution across Portugal. Results from the first nationwide survey (2011-12)Publication . Pires, Sancia; Murilhas, António; Russo, Paulo; Valério, Maria José; Gonçalves, ManuelA nationwide field sampling exercise was launched in 2011, to address mounting anecdotal evidence of atypically high honey bee colony mortalities of unexplained origin occurring throughout Portugal. The first approach was to contact 662 beekeepers (≈ 4% of the registered Portuguese beekeepers), via telephone interviews with a view to formulating an 'educated guess' regarding the cases where Nosema apis / Nosema ceranae seemed more likely to have had a role in colony mortality/morbidity. Interviewees were selected accounting for their total numbers of colonies and the geographical distribution of their apiaries across the country. The 'interviewee grid' was set to 5 beekeepers per county, fully covering continental Portugal. Following these interviews, a total of 227 apiaries (≈ 3 sampling sites per county), representing the whole continental part of the country, were sampled according to standard methodology (pooled samples of 60 foragers from the outside the hive entrance). All samples were assessed both by standard light microscopy (in a first approach to Nosema spore presence/absence) and by molecular PCR-based methodology (mainly aiming at Nosema spp. identification), as recently published in the 'BEEBOOK'. Nosema ceranae was identified in 51% of the studied apiaries across the country, ranging from 19% (in the southern 'Faro' district) up to 89% (in the northern 'Aveiro' district). Despite the fact that considerable district variation in Nosema ceranae prevalence levels were found throughout mainland Portugal, no biologically meaningful geographical pattern (either associated with north/south, inland/coastal or altitudinal transects) was observed. Nosema apis infected samples were not encountered in this study.
- Nosema distribution across Portugal. Results from the first nationwide survey (2011-12)Publication . Pires, Sancia; Murilhas, António; Russo, Paulo; Valério, Maria José; Gonçalves, ManuelNosemosis is not a recent pathology in Portugal. The etiological agent traditionally associated with it, the microsporidian Nosema apis, is well characterized and was not causing considerable economic damage to the Portuguese apiculture. However, the recent arrival, to the ‘European’ honeybee sphere, of a ‘new’ Nosema species (N. ceranae) has been recurrently considered a relevant contribution to the ‘Colony Colapse Disorder’ (CCD) and its potential to be a ‘game changer’ across the Iberian peninsula has justified the present study in Portugal. Therefore, a nationwide field sampling exercise was launched in 2011, to address mounting anecdotal evidence of atypically high honey bee colony mortalities of unexplained origin occurring throughout Portugal. The first approach was to contact 662 beekeepers (≈ 4% of the registered Portuguese beekeepers), via telephone interviews, with a view to formulating an 'educated guess' regarding the cases where N. apis / N. ceranae seemed more likely to have had a role in colony mortality/morbidity. This study appears in the context of a project submitted by FNAP Measure 6A National Beekeeping Program (under EU Regulations No. 917/2004, No. 797/2004 and No. 1234/2007), in partnership with research institutions of the authors, under coordination of Prof. Sância Pires.
- A nosemose em PortugalPublication . Russo, Paulo; Pires, Sancia; Murilhas, António; Valério, Maria JoséA mortalidade de colónias ocorrida no inverno de 2006 nos EUA e as réplicas que se seguiram, dado o contexto atual, a dimensão, a sintomatologia distinta e os ecos um pouco por todo o mundo de relatos de mortalidade idênticos, despertaram a humanidade para o risco do desaparecimento das abelhas.
- The volatile profile for discrimination of lavender and heather honey, using solid phase microextraction and gas chromatography-mass spectrometryPublication . Falcão, Soraia; Caveiro, Elsa; Russo, Paulo; Seijo-Coello, M. Carmen; Martins, Vitor Manuel Ramalheira; Vilas-Boas, MiguelHoney is a natural product produced by Apis mellifera bees from the nectar or secretions of plants, which has a long history of human consumption. It is also used in various foods and beverages as a sweetener and flavouring. The main parameters of honey quality, which also influence its price, are derived from its botanical origin. Honey volatiles have been used as markers for its authenticity. They may arise from the nectar source, from the transformation of plant compounds by the honeybee, directly generated by honeybee, from heating or handling during honey processing and storage or from microbial or environmental contamination [1]. The aim of this work is the discrimination of monofloral Lavandula spp. and Erica spp. honeys through its volatile profile. For that, eighteen samples from both lavender and heather honey, were analyzed. Volatiles were sampled by headspace solid phase microextraction (HS-SPME) using a 65 μm polydimethylsiloxane divinylbenzene (PDMS/DVB) fiber. The chemical identification was performed by gas chromatographymass spectrometry (GC-MS). A complex total ion chromatogram was obtained, with nearly seventy compounds identified and quantified. The aldehydes and terpenic derivatives were the most likely to relate honey to its floral origin, being phenylacetaldehyde and nonanal the most representative in lavender honey while hotrienol was the most abundant in the heather honeys. The above methodology was suitable for the isolation of low-molecular-weight aroma compounds, particularly for the short-chain aliphatic compounds that are important for authentication of lavender and heather honey.