scholarly journals Nosema ceranae - a new threat to honey bees (Apis mellifera)?

2021 ◽  
Author(s):  
Richard Odemer
Keyword(s):  
Honey Bee ◽  
Colony Losses ◽  
Host Switch ◽  
Nosema Species ◽  
High Prevalence ◽  
Colony Collapse ◽  
Asian Honey Bee ◽  
Seasonal Infection ◽  
Eu Project ◽  
The Eu

Back in 1900 already, the Microsporidium Nosema apis was described inApis mellifera. Thereby the Nosemosis remains without symptoms in the beehive to a certain degree. Studies indicate that infected bees have a shortened lifespan, due to a series of changes in physiological parameters. The consequence of these changes are diarrheal symptoms and the spread of infectious spores in thehive. There is also a seasonal infection course observed, which has its peak in spring time (April, May). Colloquially, the Nosemosis is therefore also known as spring shrinking craze. More recently, a new Nosema species in the European honey bee has been described, where a host-switch from the Asian honey bee A. cerana to A. mellifera has occurred. N. ceranae is blamed for colony losses in the south of Spain, many general colony losses during wintertime in Europe and has also a contribution to the Colony Collapse Disorder (CCD) in the U.S. It seems likely that the original Nosema species (N. apis) is displaced more and more by N. ceranae for unknown reasons. Within the EU project „BEE DOC“, monitoring studies on colonies in southern Germany, Switzerland, southern France, Sweden and Finland were performed. Although the high prevalence of N. ceranae could be confirmed, no increased colony mortality due to Nosemosis was recorded. This was also observed by other colleagues and thus the „new threat“ is open to debate.

scholarly journals Africanized honey bees in Colombia exhibit high prevalence but low level of infestation of Varroa mites and low prevalence of pathogenic viruses

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0244906
Author(s):  
Víctor Manuel Tibatá ◽  
Andrés Sanchez ◽  
Evan Palmer-Young ◽  
Howard Junca ◽  
Victor Manuel Solarte ◽  
...  
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Natural Resistance ◽  
Colony Losses ◽  
Africanized Honey Bees ◽  
High Prevalence ◽  
Colony Loss ◽  
Pathogenic Viruses ◽  
Low Prevalence ◽  
Bee Viruses

The global spread of the ectoparasitic mite Varroa destructor has promoted the spread and virulence of highly infectious honey bee viruses. This phenomenon is considered the leading cause for the increased number of colony losses experienced by the mite-susceptible European honey bee populations in the Northern hemisphere. Most of the honey bee populations in Central and South America are Africanized honey bees (AHBs), which are considered more resistant to Varroa compared to European honey bees. However, the relationship between Varroa levels and the spread of honey bee viruses in AHBs remains unknown. In this study, we determined Varroa prevalence and infestation levels as well as the prevalence of seven major honey bee viruses in AHBs from three regions of Colombia. We found that although Varroa exhibited high prevalence (92%), its infestation levels were low (4.5%) considering that these populations never received acaricide treatments. We also detected four viruses in the three regions analyzed, but all colonies were asymptomatic, and virus prevalence was considerably lower than those found in other countries with higher rates of mite-associated colony loss (DWV 19.88%, BQCV 17.39%, SBV 23.4%, ABPV 10.56%). Our findings indicate that AHBs possess a natural resistance to Varroa that does not prevent the spread of this parasite among their population, but restrains mite population growth and suppresses the prevalence and pathogenicity of mite-associated viruses.

scholarly journals Africanized honeybees in Colombia exhibit high prevalence but low level of infestation of Varroa mites and low prevalence of pathogenic viruses

2020 ◽  
Author(s):  
Victor Manuel Tibata ◽  
Andres Sanchez ◽  
Evan Young-Palmer ◽  
Howard Junca ◽  
Victor Manuel Solarte ◽  
...  
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Natural Resistance ◽  
Colony Losses ◽  
Africanized Honey Bees ◽  
High Prevalence ◽  
Colony Loss ◽  
Pathogenic Viruses ◽  
Low Prevalence ◽  
Bee Viruses

The global spread of the ectoparasitic mite Varroa destructor has promoted the spread and virulence of highly infectious honey bee viruses. This phenomenon is considered the leading cause for the increased number of colony losses experienced by the mite-susceptible European honey bee populations in the Northern Hemisphere. Most of the honey bee populations in Central and South America are Africanized honey bees, which are considered more resistant to Varroa compared to European honey bees . However, the relationship between Varroa levels and spread of honey bee viruses in Africanized honey bees remains unknown. In this study, we determined Varroa prevalence and infestation levels as well as the prevalence of seven major honey bee viruses in Africanized honey bees from three regions of Colombia. We found that although Varroa exhibited high prevalence (92%), its infestation levels were low (4.6%) considering that these populations never received acaricide treatments. We also detected four viruses in the three regions analyzed, but all hives were asymptomatic, and virus prevalence was considerably lower than those found in other countries with higher rates of mite-associated colony loss ( DWV 19.88%, BQCV 17.39%, SBV 23.4 %, ABPV 10.56%).   Our findings indicate that AHBs possess natural resistance to Varroa that does not prevent the spread of this parasite among their population, but restrains mite population growth and suppresses the prevalence and pathogenicity of mite-associated viruses.

scholarly journals An Overview on Honeybee Colony Losses in Buenos Aires Province, Argentina

Sociobiology ◽  
2019 ◽  
Vol 66 (1) ◽  
pp. 75 ◽  
Author(s):  
Maria Laura Genchi Garcia ◽  
Santiago Plischuk ◽  
Claudio Marcelo Bravi ◽  
Francisco Jose Reynaldi
Keyword(s):  
Honey Bees ◽  
Buenos Aires ◽  
Buenos Aires Province ◽  
Colony Collapse Disorder ◽  
Colony Losses ◽  
High Prevalence ◽  
Different Types ◽  
Colony Collapse ◽  
Honeybee Colony

Honey bees (Apis mellifera) are essential for the ecosystem, so their loss threatens biodiversity and agriculture. Several factors have been proposed as possible causes of both massive losses and Colony Collapse Disorder. In August 2017 episodes of colony losses were registered in General Alvear, Buenos Aires province. The aim of the present study was to find possible causes of these events. The samples were screened for presence of several pathogens and the determination of maternal lineages was also performed. Seven out of ten colonies were positive for pathogens, but there was no high prevalence of any of them. It will be necessary to carry out a standardization of studies, and delineate boundaries that allow comparing cases in order to discriminate different types of mortality of colonies that occur worldwide.

scholarly journals Efficient and Consumer-Centered Item Detection and Classification with a Multicamera Network at High Ranges

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4818
Author(s):  
Nils Mandischer ◽  
Tobias Huhn ◽  
Mathias Hüsing ◽  
Burkhard Corves
Keyword(s):  
Machine Learning ◽  
Shop Floor ◽  
Unsupervised Segmentation ◽  
User Friendliness ◽  
Industrial Environment ◽  
Machine Learning Methods ◽  
Eu Project ◽  
Detection And Localization ◽  
Industrial Context ◽  
The Eu

In the EU project SHAREWORK, methods are developed that allow humans and robots to collaborate in an industrial environment. One of the major contributions is a framework for task planning coupled with automated item detection and localization. In this work, we present the methods used for detecting and classifying items on the shop floor. Important in the context of SHAREWORK is the user-friendliness of the methodology. Thus, we renounce heavy-learning-based methods in favor of unsupervised segmentation coupled with lenient machine learning methods for classification. Our algorithm is a combination of established methods adjusted for fast and reliable item detection at high ranges of up to eight meters. In this work, we present the full pipeline from calibration, over segmentation to item classification in the industrial context. The pipeline is validated on a shop floor of 40 sqm and with up to nine different items and assemblies, reaching a mean accuracy of 84% at 0.85 Hz.

Morphological differentiation in Asian honey bee (Apis cerana) populations in the basin and highlands of southwestern China

2017 ◽  
Vol 56 (3) ◽  
pp. 203-209 ◽  
Author(s):  
Xiangjie Zhu ◽  
Shujing Zhou ◽  
Xinjian Xu ◽  
Jianwen Wang ◽  
Yinglong Yu ◽  
...  
Keyword(s):  
Honey Bee ◽  
Apis Cerana ◽  
Morphological Differentiation ◽  
Southwestern China ◽  
Asian Honey Bee

scholarly journals A national survey of managed honey bee 2015–2016 annual colony losses in the USA

2017 ◽  
Vol 56 (4) ◽  
pp. 328-340 ◽  
Author(s):  
Kelly Kulhanek ◽  
Nathalie Steinhauer ◽  
Karen Rennich ◽  
Dewey M Caron ◽  
Ramesh R Sagili ◽  
...  
Keyword(s):  
Honey Bee ◽  
National Survey ◽  
Colony Losses ◽  
The Usa

Deep renovation up to zero energy through Add-ons: the ABRACADABRA Project

2019 ◽  
Author(s):  
Annarita Ferrante ◽  
Fabrizio Ungaro ◽  
Giovanni Semprini ◽  
Lorna Dragonetti ◽  
Elettra Agliardi ◽  
...  
Keyword(s):  
Cost Effective ◽  
Urban Environments ◽  
Zero Energy ◽  
Urban Context ◽  
Building Stock ◽  
Existing Building ◽  
The Real Estate ◽  
International Projects ◽  
Eu Project ◽  
The Eu

<p>and international projects</p><p>various EU H2020 projects</p><p>Though housing is one of the most energy consumer sectors, it is currently extremely underestimated, because of a clear investment gap due to economic, social and legislative barriers. The EU project ABRACADABRA (Assistant Building to Retrofit, Adopt, Cure And Develop the Actual Buildings up to zeRo energy, Activating a market for deep renovation) is based on the idea that the real estate value increase given by the appropriate densification strategy in urban environments could be an opportunity to activate a market for deep energy renovation. To prove the effectiveness of the strategy more than 70 case studies throughout the EU cities have been assessed by means of a cost-effective analysis. Basing on the parametric variation of the different values involved (cost of construction, energy, etc.) the benefit of this strategy has been proved in the majority of the different building types and contexts.</p><p>More interestingly, the ABRA strategy has been simulated and tested outside Europe in order to verify its scalability and the possibility of considering other non-energy related benefits in the renovation of the existing building stock. A specific study on the NYC urban context has been conducted to effectively adapt the strategy and combine the global drivers of energy consumption reduction and CO<span>2</span> emission reduction with the local need of combating flood emergency and related flood-proofing measures.</p><p>The results reached by this work demonstrate how the energy retrofit trough add-ons reduces significantly the payback times of the investments, preserve soil consumption, while providing a extraordinary opportunity to enhance urban resiliency by challenging the local emergencies.</p>

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