Felicioli Antonio, Forzan Mario, Sagona Simona, D'Agostino Paola, Baido Diego, Fronte Baldassare, Mazzei Maurizio
Department of Veterinary Science, University of Pisa, Viale delle Piagge 2, 56100 Pisa, Italy.
Interdepartmental Research Center "Nutraceuticals and Food for Health", University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy.
Vet Sci. 2020 Apr 25;7(2):52. doi: 10.3390/vetsci7020052.
Honeybee pathogens have an important role in honeybee colony mortality and colony losses; most of them are widely spread and necessitate worldwide solutions to contrast honeybee's decline. Possible accepted solutions to cope with the spread of honeybee's pathogens are focused on the study of experimental protocols to enhance the insect's immune defenses. Honeybee's artificial diet capable to stimulate the immune system is a promising field of investigation as ascertained by the introduction of 1,3-1,6 β-glucans as a dietary supplement. In this work, by collecting faecal samples of honeybees exposed to different dietary conditions of 1,3-1,6 β-glucans (0.5% and 2% w/w), it has been possible to investigate the Deformed wing virus (DWV) viral load kinetic without harming the insects. Virological data obtained by a one-step TaqMan RT-PCR highlighted the ability of 1,3-1,6 β-glucans to reduce the viral load at the 24th day of rearing. The results indicated that the diet supplemented with 1,3-1,6 β-glucans was associated with a dose-dependent activation of phenoloxidase. The control group showed a higher survival rate than the experimental groups. This research confirmed 1,3-1,6 β-glucans as molecules able to modulate honeybees' defense pathways, and this is the first report in which the kinetic of DWV infection in honeybee faeces has been monitored by a RT-qPCR.
蜜蜂病原体在蜜蜂蜂群死亡和蜂群损失中起着重要作用；其中大多数广泛传播，需要全球范围内的解决方案来应对蜜蜂数量的减少。应对蜜蜂病原体传播的可能被接受的解决方案集中在研究增强昆虫免疫防御的实验方案上。如通过引入1,3 - 1,6β - 葡聚糖作为膳食补充剂所确定的那样，能够刺激免疫系统的蜜蜂人工饲料是一个有前景的研究领域。在这项工作中，通过收集暴露于不同1,3 - 1,6β - 葡聚糖膳食条件（0.5%和2% w/w）下的蜜蜂粪便样本，得以在不伤害昆虫的情况下研究变形翅病毒（DWV）的病毒载量动态。通过一步法TaqMan RT - PCR获得的病毒学数据突出了1,3 - 1,6β - 葡聚糖在饲养第24天时降低病毒载量的能力。结果表明，添加1,3 - 1,6β - 葡聚糖的饲料与酚氧化酶的剂量依赖性激活有关。对照组的存活率高于实验组。这项研究证实1,3 - 1,6β - 葡聚糖是能够调节蜜蜂防御途径的分子，这是首次通过RT - qPCR监测蜜蜂粪便中DWV感染动态的报告。
