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  1. #101

    Default Re: CCD/Neonicotinoid Data (Studies, Articles, Links)

    Neonicotinoid pesticides severely affect honey bee queens
    Geoffrey R. Williams, Aline Troxler, Gina Retschnig, Kaspar Roth, Orlando Yañez, Dave Shutler, Peter Neumann*& Laurent Gauthier
    Scientific Reports 5, Article*number:*14621 (2015)
    Published online: 13 October 2015

  2. #102

    Default Re: CCD/Neonicotinoid Data (Studies, Articles, Links)

    A new study has found neonicotinoids, the world’s most commonly used insecticide, cause queen honeybees to lay as much as two-thirds fewer eggs, jeopardizing the health and stability of entire bee colonies.

  3. #103

    Default Re: CCD/Neonicotinoid Data (Studies, Articles, Links)

    "Our results strongly suggest that neonicotinoids can negatively affect honeybee drone sperm quality."

    Sperm parameters of honeybee drones exposed to imidacloprid

    Ciereszko, A., Wilde, J., Dietrich, G.J. et al. Apidologie (2016). doi:10.1007/s13592-016-0466-2

    The objective of this study was to evaluate the effects of chronical exposure of honeybee drones to environmental (5 ppb) and non-environmental concentration (200 ppb) of imidacloprid (IMD) on sperm concentration, motility, viability, and mitochondrial membrane potential measured in semen obtained from 180 drones originating from 18 colonies. The results demonstrate that IMD exposure did not affect sperm concentration; however, there were significant differences in concentration within colonies. IMD exposure was associated with reductions in sperm motility, which also varied within colonies. Statistically significant interactions between IMD exposure and colony were found for active mitochondria and sperm viability. Our results strongly suggest that neonicotinoids can negatively affect honeybee drone sperm quality. It is important to emphasize that IMD actions can be strongly modulated according to the colony.

  4. #104

    Default Re: CCD/Neonicotinoid Data (Studies, Articles, Links)

    Effects of sublethal concentration of imidacloprid on the insulin/insulin-like signaling pathway in the honey bee, Apis mellifera

    Colony collapse disorder (CCD), a phenomenon of honeybees disappearance, has been reported since 2006. Chronic exposure to neonicotinoid insecticides, particularly imidacloprid, has been suggested to impair forager’s ability for foraging and be a main cause of CCD. Recently, it has been reported that imidacloprid induces insulin resistance in animal cell line by blocking glucose uptake. Similarly to human insulin, insulin-like peptide (ILP) of insects is involved in maintaining blood glucose contents in hemolymph by regulating the concentration of trehalose and glycogen. Therefore, we have hypothesized that sublethal concentration of neonicotinoid may affect the metabolic pathway of honey bees as well. We investigated the transcription levels of the genes involved in the insulin/insulin-like signaling (IIS) pathway, such as AmILP and AmInR, following an acute or a chronic dietary exposure of sublethal concentrations of imidacloprid to foragers. In both experiments, honeybees showed increased expression levels of ILP and InR in a dose-dependent manner. Our results suggest that sublethal dose of imidacloprid likely upregulates IIS pathway, thereby rendering honey bees to become resistant to insulin.

  5. #105

    Default Re: CCD/Neonicotinoid Data (Studies, Articles, Links)

    Another scientific review on neonics:

  6. #106

    Default Re: CCD/Neonicotinoid Data (Studies, Articles, Links)

    Sublethal doses of neonicotinoid imidacloprid can interact with honey bee chemosensory protein 1 (CSP1) and inhibit its function
    Hongliang Li, Jing Tan, Xinmi Song, Fan Wu, Mingzhu Tang, Qiyun Hua, Huoqing Zheng, Fuliang Hu
    Biochemical and Biophysical Research Communications, Available online 14 March 2017, ISSN 0006-291X,

    Abstract: Abstract
    As a frequently used neonicotinoid insecticide, imidacloprid can impair the chemoreceptive behavior of honey bees even at sublethal doses, while the physiochemical mechanism has not been further revealed. Here, multiple fluorescence spectra, thermodynamic method, and molecular docking were used to study the interaction and the functional inhibition of imidacloprid to the recombinant CSP1 protein in Asian honey bee, Apis cerana. The results showed that the fluorescence intensity (λem = 332 nm) of CSP1 could be significantly quenched by imidacloprid in a dynamic mode. During the quenching process, ΔH > 0, ΔS > 0, indicating that the acting forces of imidacloprid with CSP1 are mainly hydrophobic interactions. Synchronous fluorescence showed that the fluorescence of CSP1 was mainly derived from tryptophan, and the hydrophobicity of tryptophan decreased with the increase of imidacloprid concentration. Molecular docking predicted the optimal pose and the amino acid composition of the binding process. Circular dichroism (CD) spectra showed that imidacloprid reduced the α-helix of CSP1 and caused the extension of the CSP1 peptide chain. In addition, the binding of CSP1 to floral scent β-ionone was inhibited by nearly 50% of the apparent association constant (KA) in the presence of 0.28–2.53 ng/bee of imidacloprid, and the inhibition rate of nearly 95% at 3.75 ng/bee of imidacloprid at sublethal dose level. This study initially revealed the molecular physiochemical mechanism that sublethal doses of neonicotinoid still interact and inhibit the physiological function of the honey bees' chemoreceptive system.
    Keywords: Apis cerana; Chemosensory protein; Neonicotinoid imidacloprid; Binding interaction; Functional inhibition

    Consequences of the impairment?

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