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The high overwinter mortalities in the honey bee population of Apis mellifera have been linked to immunocompromised individuals experiencing nutritional limitations. Larval nutrition plays a crucial role in determining the successful development of adults, making them more susceptible to bacterial diseases when undernourished. One of the main intracellular signalling pathways in the larval immune system against bacterial diseases is the Toll receptor signalling pathway, which activates antimicrobial peptides like defensin. Inadequate nutrition also disrupts the redox balance on A. mellifera individuals, with superoxide dismutase and catalase being the key components of their antioxidant system. Vitellogenin is associated with the mobilization of nutrients in early A. mellifera bee stages. Considering that Saccharomyces cerevisiae is the second most significant by‐product of the brewing industry, it may serve as a valuable raw material. We investigated the impact of feeding larvae with live S. cerevisiae cells on the relative expression of their main immune and antioxidant‐related genes. To assess gene expression, we conducted RT‐qPCR, using RNA extracted from ten larvae per treatment on the seventh day when the feeding trial concluded. Importantly, the presence of S. cerevisiae did not affect larval survival compared to the control group. However, the relative expression of immune‐related gene toll18W and antioxidant‐related gene sod in larvae fed with live S. cerevisiae cells was significantly higher than in larvae that were not fed with them. This suggests that the inclusion of S. cerevisiae in their diet may provide larvae with a nutritional advantage. Additionally, the vitellogenin (vg) gene expression increased in treated larvae compared to the control group, potentially facilitating their access to nutrients and, consequently, enhancing their ability to cope with nutritional stress. [ABSTRACT FROM AUTHOR]

Bumble bees of the genus Bombus spp. play a key role as effective pollinators in the biodiversity rich Central Andean region; however, parasites and pathogens may negatively influence their abundance and population numbers. In this study, we aimed at verifying the occurrence of these natural enemies in the Andes regions of Bolivia and Peru. Workers and males of Bombus funebris, Bombus opifex and Bombus pauloensis were collected in three localities from highlands at ~1,700 m.a.s.l. Analyses by both optical and molecular techniques revealed the presence of the Apis mellifera filamentous virus (AmFV), the microsporidium Vairimorpha ceranae, the flagellates Crithidia bombi and Lotmaria passim, and five species of mites in the genera Parasitellus Willmann, Pneumolaelaps Berlese, Proctolaelaps Berlese, Tyrophagus Oudemans, and Kuzinia Zachvatkin. Given the potential entry of the allochthonous bumble bee Bombus terrestris to the region, this information is essential to evaluate autochtonous biodiversity conservation strategies. [ABSTRACT FROM AUTHOR]

Chronic bee paralysis virus (CBPV) is a positive single-stranded RNA virus that exhibits a worldwide distribution. Although the effects of this virus on honeybees' health are well known, its presence in other bee species has not been fully studied. In this work, CBPV was detected in several native bees from Argentina, including Bombus pauloensis, Halictillus amplilobus, Peponapis fervens, and members of the genus Xylocopa. Here, we report for the first time the presence of CBPV in native bees from South America. [ABSTRACT FROM AUTHOR]

Phoretic mites associated with bumblebees are considered commensals that represent little or no risk for their hosts. The aim of the present study was to assess the potential role of the phoretic mites Pneumolaelaps longanalis and Parasitellus fucorum, as carriers of parasites that are known to affect bees. Mites were extracted from bumblebees dating between 1945 and 1981 which belong to museum collections, and from a freshly collected queen. The DNA was extracted and amplified, and the final products were sequenced and analyzed. Parasite's DNA was found in all samples. Ascosphaera spp., Crithidia bombi, Lotmaria passim, and Nosema ceranae were present in both mite species. Moreover, DNA from Apis mellifera filamentous virus (AmFV), Apicystis bombi, Ascosphaera apis, Nosema apis, and Nosema bombi was found in P. longanalis. This study represents the oldest report of parasite's DNA in bumblebee phoretic mites, highlighting the relevance of museum samples for historical studies in parasitology. [ABSTRACT FROM AUTHOR]

Apis mellifera filamentous virus (AmFV) is a large double stranded DNA virus of honey bees and its prevalence and relationship with other parasites is poorly known. Samples consisted of fifty-one adult bees belonging to eight native species collected using entomological nets in six provinces of Argentina, from 2009 to 2018. Total genomic DNA was extracted from individual bees and a 551 bp fragment of the Bro-N gene of AmFV was amplified by qPCR. In the present work we have reported for the first time both the presence and the wide geographic distribution of AmFV in Argentinian species of native bees. This is the first report of the presence of this virus associated with Xylocopa atamisquensis, X. augusti, X. frontalis, X. spendidula, Bombus pauloensis and Peponapis fervens. Detecting pathogens that could threaten native bee health is of outmost importance to generate both conservation and management strategies. [ABSTRACT FROM AUTHOR]

The honey bee tracheal mite Acarapis woodi is an internal obligate parasite of adult honey bees (Apis mellifera). The small size of the mites and location within the bee's trachea create a challenge for diagnostic identification. Detailed assessment of low-level mite infestation involves microscopic examination of the bee's tracheae, but this traditional diagnostic method takes a long time. In recent years, new molecular diagnostic techniques have been developed to identify A. woodi with the use of PCRs. The purpose of this study was to compare the diagnostic sensitivity of microscopic examination and qPCR method for the detection of A. woodi in honey bee samples. Thirty-six samples were analyzed with both methods and qPCR was more sensitive than the microscopic method to detect A. woodi. This work demonstrates the practical application of molecular technology as a support tool for surveys and contingency management and to provide robust surveillance data on the presence or absence of A. woodi in honey bee colonies. [ABSTRACT FROM AUTHOR]

Transmission of viruses by Varroa destructor Anderson & Trueman to bees has been identified as one of the main threats to Apis mellifera L. colonies. It has also been suggested that synergistic parasite-pathogen interaction mediated by A. mellifera immunity can drive the collapse of honey bee colonies. We analyzed the relationship between deformed wing virus (DWV) viral load and gene expression levels of Toll Wheeler, cactus, domeless, TEPA, nitric oxide synthase, hymenoptaecin, vitellogenin, defensin, abaecin in winter bee samples of A. mellifera with and without deformed wings. Samples were collected from hives in the field with high V. destructor infestation. In bees with deformed wings we found an increase in DWV titre and upregulation of genes in the Jak-STAT signalling pathway. [ABSTRACT FROM AUTHOR]

The primary food of adult honey bees ( Apis mellifera) is honey prepared by bees from nectar, provided by plants in order to stimulate the bee's pollination service. Nectar consists of carbohydrates, amino acids and water, as well as other minor compounds whose proportion varies among plant species and whose biological implications in the honey bee physiology require intense research. Several environmental stressors are causing the decline of bee colonies, and thereby, we tried to connect the nutritional quality of bee's diet with the strength of the bee's immune system. The phytohormone abscisic acid (ABA) is present in nectar, honey and adult honey bees. It has been demonstrated that ABA stimulates innate immune defences in animal cells. However, the influence of ABA on A. mellifera's health and fitness is unknown. Here, we show that honey bees fed with an ABA supplement in field experiments resulted in (i) the appearance of ABA in larvae and adult bees, (ii) enhanced haemocyte response to non-self recognition, (iii) improved wound healing and granulocyte and plasmatocyte activation and (iv) maximum adult bee population after the winter and increased pesticide tolerance. The results indicate that the naturally occurring compound ABA has a positive influence in honey bee immunity. ABA emerges as a potent booster of immune defence in A. mellifera and may be useful in addressing the colony losses threatening apiculture and pollination service worldwide. [ABSTRACT FROM AUTHOR]

Lotmaria passim (Kinetoplastea) is considered the most prevalent as well as the most virulent trypanosomatid associated to the European honey bee Apis mellifera. We used qPCR to screen for the presence of this parasite in 57 samples from ten Argentinian provinces, and were able to detect its presence throughout most of the country with 41% of the samples testing positive. In a retrospective analysis, we detected L. passim in 73% of honey bee samples from 2006 showing that this flagellate has been widely present in Argentina for at least ~15 years. Additionally, three primer sets for L. passim detection were compared, with the pair that produced smallest PCR product having the best detection capability. Finally, we also found L. passim DNA in 100% (n = 6) of samples of the mite Varroa destructor. The role of this ectoparasite in the lifecycle of Lotmaria , if any, remains unrevealed. Unlabelled Image • The trypanosomatid Lotmaria passim is widely present in Argentina since 2006. • Forty-one percent of the analyzed honey bees were Lotmaria passim -positive. • All analyzed Varroa destructor individuals harbored DNA of Lotmaria passim. [ABSTRACT FROM AUTHOR]

The high annual losses of managed honey bees (Apis mellifera) has attracted intensive attention, and scientists have dedicated much effort trying to identify the stresses affecting bees. There are, however, no simple answers; rather, research suggests multifactorial effects. Several works have been reported highlighting the relationship between bees' immunosuppression and the effects of malnutrition, parasites, pathogens, agrochemical and beekeeping pesticides exposure, forage dearth and cold stress. Here we analyze a possible connection between immunity-related signaling pathways that could be involved in the response to the stress resulted from Varroa-virus association and cold stress during winter. The analysis was made understanding the honey bee as a superorganism, where individuals are integrated and interacting within the colony, going from social to individual immune responses. We propose the term "Precision Nutrition" as a way to think and study bees' nutrition in the search for key molecules which would be able to strengthen colonies' responses to any or all of those stresses combined. [ABSTRACT FROM AUTHOR]

This correction stands to correct the last sentence found in the caption of Figure 2 where it reads, "Three independent experiments were performed and a total of 18 larvae per treatment were analyzed." [ABSTRACT FROM AUTHOR]