But maybe the issue is yours, from post #1 in this thread:
"Use this thread to post Articles, Studies or Links that apply to the topic of CCD.
This will allow members to have all supporting data in one place.
This thread is NOT for discussion.
Post supporting data only. Discuss data in other threads."
Effect of Sublethal Doses of Clothianidin and/or V. destructor on Honey Bee (Apis mellifera L.) Health, Behavior and Associated Gene Expression
Autor: Morfin Ramirez, Nuria
Department: School of Environmental Sciences
Program: Environmental Sciences
Advisor: Guzman-Novoa, Ernesto
Little is known about the effects of sublethal doses of neonicotinoids on honey bee (Apis mellifera L.) behaviors and mortality, and whether those effects are altered with parasitism by V. destructor. This study examined the effects of multiple exposures to field-realistic sublethal doses of clothianidin with and without V. destructor on adult bees and newly emerged bees treated as larvae. For adult exposure, memory retention decreased with each stressor alone, but weight and sugar consumption decreased only by the effect of V. destructor. For larval exposure, haemocyte counts increased with clothianidin but decreased with V. destructor, clothianidin reduced hygienic behavior and the number of foraging trips of the adults that emerged. Interactions between the stressors were observed as decreased weight of newly emerged bees with larval exposure, an increased mortality in adult bees, and a decreased intense grooming behavior with adult exposure. The relative expression of several immune and neural related honey bee genes showed an interaction between the stressors using two-way ANOVA in many cases. Also, the dose response of gene expression often revealed a non-linear pattern, implying hormesis, although hormesis was not detected for any of the biological measurements. For example, AmpUf68 expression in newly emerged bees showed an interaction between the stressors with a J-shaped dose response to clothianidin and no dose response to clothianidin plus V. destructor, while AmDef-2 expression in adults showed an interaction between stressors with an inverted U-shaped dose response to clothianidin and a sigmoidal dose response to clothianidin plus V. destructor. RNAseq analysis of bees with the highest sublethal doses of clothianidin with and without V. destructor showed no changes in the magnitude of expression but reduced numbers of differentially expressed genes with the combined stressors compared to each stressor alone. However, novel differentially expressed genes were also observed with the combined stressors. The combined stressors appeared to both change and inhibit the numbers of differentially expressed genes compared to each stressor alone. In general, clothianidin and V. destructor have different effects on bee health and behavior that was only rarely affected when combined, whereas gene expression mostly had reduced and unpredictable, rather than additive, effects with the combined stressors.
European Food Safety Authority:
Neonicotinoids: risks to bees confirmed
Sci Total Environ. 2018 Feb 27;630:487-494. doi: 10.1016/j.scitotenv.2018.02.258. [Epub ahead of print]
Enhancement of chronic bee paralysis virus levels in honeybees acute exposed to imidacloprid: A Chinese case study.
Diao Q1, Li B1, Zhao H2, Wu Y1, Guo R3, Dai P1, Chen D3, Wang Q1, Hou C4.
Though honeybee populations have not yet been reported to be largely lost in China, many stressors that affect the health of honeybees have been confirmed. Honeybees inevitably come into contact with environmental stressors that are not intended to target honeybees, such as pesticides. Although large-scale losses of honeybee colonies are thought to be associated with viruses, these viruses usually lead to covert infections and to not cause acute damage if the bees do not encounter outside stressors. To reveal the potential relationship between acute pesticides and viruses, we applied different doses of imidacloprid to adult bees that were primarily infected with low levels (4.3×105 genome copies) of chronic bee paralysis virus (CBPV) to observe whether the acute oral toxicity of imidacloprid was able to elevate the level of CBPV. Here, we found that the titer of CBPV was significantly elevated in adult bees after 96h of acute treatment with imidacloprid at the highest dose 66.9ng/bee compared with other treatments and controls. Our study provides clear evidence that exposure to acute high doses of imidacloprid in honeybees persistently infected by CBPV can exert a remarkably negative effect on honeybee survival. These results imply that acute environmental stressors might be one of the major accelerators causing rapid viral replication, which may progress to cause mass proliferation and dissemination and lead to colony decline. The present study will be useful for better understanding the harm caused by this pesticide, especially regarding how honeybee tolerance to the viral infection might be altered by acute pesticide exposure.
Surprisingly to some, science does not deal in proof, in spite of the word being associated with science a whole lot more than perhaps it should be. https://rationalwiki.org/wiki/Proof
We can demonstrate, suggest, and convince ourselves that a scientific truth is valid. But proof? That's an impossibility for science. https://www.forbes.com/sites/startsw...oof-is-a-myth/
While the phrase "scientific proof" is often used in the popular media, many scientists have argued that there is really no such thing. For example, Karl Popper once wrote that "In the empirical sciences, which alone can furnish us with information about the world we live in, proofs do not occur, if we mean by 'proof' an argument which establishes once and for ever the truth of a theory,". https://en.wikipedia.org/wiki/Scientific_evidence
A Heretics Guide to Beekeeping http://heretics-guide.atwebpages.com/
SiWolke, there has been discussion taking place in all 8 pages of this thread, even by yourself. Perhaps you would like only discussion favouring only your point of view? As a beekeeper surrounded by agriculture using neonics I generally have less than a 10% loss each year. However I had a small yard where I could not keep my colonies alive and one day while visiting that yard I saw a neighbor spraying in his vegetable garden so I wandered over there and asked what he was spraying with to which he replied Sevin, well I no longer keep bees there as I know why I could not keep them alive.
Now the moral of the story is Neonics could harm bees, it is an insecticide but some of the stuff the Ag sector used to use before Neonics was a lot worse and killed a lot more bees. And the story about proof, who needs proof when we have a consensus of scientists just like the consensus of scientists who believed the world was flat before Gallileo came along well you know that story. It appears that today the consensus of scientists is mainly a consensus of political science graduates.
A Heretics Guide to Beekeeping http://heretics-guide.atwebpages.com/
There are many other threads in this sub forum with discussion about the topics.
that´s interesting, please post your links if they are contradiction
Bernhard, many thanks for keeping us updated.
Last edited by 1102009; 03-15-2018 at 10:26 AM.
From the abstract "honey bee larvae received a single treatment dose (4.28 ng thiamethoxam/queen larva on the 4th day after larvae grafting in artificial queen cells), while the second honey bee queen rearing cycle received a double treatment dose (total of 8.56 ng thiamethoxam/queen larva on the 4th and 5th day after larvae grafting in artificial queen cells)."
I do not see how injecting thiamethoxam into a developing queen cell ever occurs in the "field."
Influences of acephate and mixtures with other commonly used pesticides on honey bee (Apis mellifera) survival and detoxification enzyme activities
Jianxiu Yaoa, Yu Cheng Zhua, John Adamczyk, Randall Luttrell
Acephate (organophosphate) is frequently used to control piercing/sucking insects in field crops in southern United States, which may pose a risk to honey bees. In this study, toxicity of acephate (formulation Bracket®97) was examined in honey bees through feeding treatments with sublethal (pollen residue level: 0.168 mg/L) and median-lethal (LC50: 6.97 mg/L) concentrations. Results indicated that adult bees treated with acephate at residue concentration did not show significant increase in mortality, but esterase activity was significantly suppressed. Similarly, bees treated with binary mixtures of acephate with six formulated pesticides (all at residue dose) consistently showed lower esterase activity and body weight. Clothianidin, λ-cyhalothrin, oxamyl, tetraconazole, and chlorpyrifos may interact with acephate significantly to reduce body weight in treated bees. The dose response data (LC50: 6.97 mg/L) revealed a relatively higher tolerance to acephate in Stoneville bee population (USA) than populations elsewhere, although in general the population is still very sensitive to the organophosphate. In addition to killing 50% of the treated bees acephate (6.97 mg/L) inhibited 79.9%, 20.4%, and 29.4% of esterase, Glutathione S-transferase (GST), and acetylcholinesterase (AChE) activities, respectively, in survivors after feeding treatment for 48 h. However, P450 activity was elevated 20% in bees exposed to acephate for 48 h. Even though feeding on sublethal acephate did not kill honey bees directly, chronic toxicity to honey bee was noticeable in body weight loss and esterase suppression, and its potential risk of synergistic interactions with other formulated pesticides should not be ignored.
Have a quick look at:
That's an ad from the manufacturer of the pesticide. Read carefully what a neonic does. It boils down to: chemical plus nature. The rest is self-explaining.
Good luck to you all. Gonna be tough times, for both: bees and beekeepers that make a living from their bees.
Carreck, Norman and Ratnieks, Francis (2014) The dose makes the poison: have "field realistic" rates of exposure of bees to neonicotinoid insecticides been overestimated in laboratory studies? Journal of Apicultural Research, 53 (5). pp. 607-614. ISSN 0021-8839
|"Recent laboratory based studies have demonstrated adverse sub-lethal effects of neonicotinoid insecticides on honey bees and bumble bees, and these studies have been influential in leading to a European Union moratorium on the use of three neonicotinoids, clothianidin, imidacloprid, and thiamethoxam on "bee attractive" crops. Yet so far, these same effects have not been observed in field studies. Here we review the three key dosage factors (concentration, duration and choice) relevant to field conditions, and conclude that these have probably been over estimated in many laboratory based studies."
Three years of banning neonicotinoid insecticides based on sub‐lethal effects: can we expect to see effects on bees?
Tjeerd Blacquière Jozef JM van der Steen
First published: 03 April 2017 https://doi.org/10.1002/ps.4583 Cited by: 4
Although no direct relationship between colony losses and the decline of numbers of honey bee colonies could be shown (see section 4), losses of a high number of colonies over winter are considered to be a problem in itself for beekeepers, and have stimulated the foundation of the Coloss network.14 So could honey bee colony losses experienced by beekeepers be attributed to the use of neonicotinoids? Smith et al.11 point out that the evidence is not strong for the case. Even a very extensive 4‐year monitoring project set‐up with the intention to shed light on the possible factors involved in honey bee colony losses, and specifically focusing on residues of chemicals,19 was not able to show any relationship with these, but did show effects of infestation with the Varroa mite, some viruses and the age of the queen: actually all being part of the management choices of the beekeeper, a decisive factor often overlooked.
Environ Health Perspect; DOI:10.1289/EHP515
Effects of Neonicotinoid Pesticide Exposure on Human Health: A Systematic Review
Andria M. Cimino,1 Abee L. Boyles,2 Kristina A. Thayer,2 and Melissa J. Perry1
To the authors’ knowledge, this is the first systematic review of the literature on human health effects of neonicotinoids. As reviewed here, four studies reported low rates of adverse health effects from acute neonic exposure. Even the most severe outcomes, including two fatalities, may have been mediated by other factors (age, underlying health conditions, undetected coexposures). The acute poisoning studies did, however, elucidate clinical findings important for the diagnosis and treatment of acute neonic exposures, including a better understanding of neonic toxicokinetics in humans. The other four studies reported associations between chronic neonic exposure and adverse developmental outcomes or a symptom cluster including neurological effects. The findings of animal studies support the biological plausibility for such associations (Abou-Donia et al. 2008; Gibbons et al. 2015; Gu et al. 2013; Kimura-Kuroda et al. 2012; Li et al. 2011; Mason et al. 2013; Tomizawa 2004).
Although the studies in this review represent an important contribution to the literature, particularly given the lack of any general population chronic exposure studies prior to 2014, there remains a paucity of data on neonic exposure and human health. Given the widespread use of neonics in agriculture and household products and its increasing detection in U.S. food and water, more studies on the human health effects of chronic (non-acute) neonic exposure are needed.
Glyphosate perturbs the gut microbiota of honey bees.
Effects of sublethal doses of glyphosate on honeybee navigation